diff --git a/modules/ppcp-api-client/src/Repository/PartnerReferralsData.php b/modules/ppcp-api-client/src/Repository/PartnerReferralsData.php
index af8bae174..01a91f9b6 100644
--- a/modules/ppcp-api-client/src/Repository/PartnerReferralsData.php
+++ b/modules/ppcp-api-client/src/Repository/PartnerReferralsData.php
@@ -5,7 +5,7 @@
  * @package WooCommerce\PayPalCommerce\ApiClient\Repository
  */
 
-declare(strict_types=1);
+declare( strict_types = 1 );
 
 namespace WooCommerce\PayPalCommerce\ApiClient\Repository;
 
@@ -18,43 +18,21 @@ class PartnerReferralsData {
 	/**
 	 * The DCC Applies Helper object.
 	 *
+	 * @deprecated Deprecates with the new UI. In this class, the products are
+	 *             always explicit, and should not be deducted from the
+	 *             DccApplies state at this point.
+	 *             Remove this with the legacy UI code.
 	 * @var DccApplies
 	 */
-	private $dcc_applies;
-
-	/**
-	 * The list of products ('PPCP', 'EXPRESS_CHECKOUT').
-	 *
-	 * @var string[]
-	 */
-	private $products;
+	private DccApplies $dcc_applies;
 
 	/**
 	 * PartnerReferralsData constructor.
 	 *
 	 * @param DccApplies $dcc_applies The DCC Applies helper.
 	 */
-	public function __construct(
-		DccApplies $dcc_applies
-	) {
+	public function __construct( DccApplies $dcc_applies ) {
 		$this->dcc_applies = $dcc_applies;
-		$this->products    = array(
-			$this->dcc_applies->for_country_currency() ? 'PPCP' : 'EXPRESS_CHECKOUT',
-		);
-	}
-
-	/**
-	 * Returns a new copy of this object with the given value set.
-	 *
-	 * @param string[] $products The list of products ('PPCP', 'EXPRESS_CHECKOUT').
-	 * @return static
-	 */
-	public function with_products( array $products ): self {
-		$obj = clone $this;
-
-		$obj->products = $products;
-
-		return $obj;
 	}
 
 	/**
@@ -62,82 +40,119 @@ class PartnerReferralsData {
 	 *
 	 * @return string
 	 */
-	public function nonce(): string {
+	public function nonce() : string {
 		return 'a1233wtergfsdt4365tzrshgfbaewa36AGa1233wtergfsdt4365tzrshgfbaewa36AG';
 	}
 
 	/**
 	 * Returns the data.
 	 *
+	 * @param string[] $products          The list of products to use ('PPCP', 'EXPRESS_CHECKOUT').
+	 *                                    Default is based on DCC availability.
+	 * @param string   $onboarding_token  A security token to finalize the onboarding process.
+	 * @param bool     $use_subscriptions If the merchant requires subscription features.
+	 * @param bool     $use_card_payments If the merchant wants to process credit card payments.
 	 * @return array
 	 */
-	public function data(): array {
+	public function data( array $products = array(), string $onboarding_token = '', bool $use_subscriptions = null, bool $use_card_payments = true ) : array {
+		if ( ! $products ) {
+			$products = array(
+				$this->dcc_applies->for_country_currency() ? 'PPCP' : 'EXPRESS_CHECKOUT',
+			);
+		}
+
 		/**
-		 * Returns the partners referrals data.
+		 * Filter the return-URL, which is called at the end of the OAuth onboarding
+		 * process, when the merchant clicks the "Return to your shop" button.
 		 */
-		return apply_filters(
-			'ppcp_partner_referrals_data',
-			array(
-				'partner_config_override' => array(
-					/**
-					 * Returns the URL which will be opened at the end of onboarding.
-					 */
-					'return_url'             => apply_filters(
-						'woocommerce_paypal_payments_partner_config_override_return_url',
-						admin_url( 'admin.php?page=wc-settings&tab=checkout&section=ppcp-gateway' )
-					),
-					/**
-					 * Returns the description of the URL which will be opened at the end of onboarding.
-					 */
-					'return_url_description' => apply_filters(
-						'woocommerce_paypal_payments_partner_config_override_return_url_description',
-						__( 'Return to your shop.', 'woocommerce-paypal-payments' )
-					),
-					'show_add_credit_card'   => true,
+		$return_url = apply_filters(
+			'woocommerce_paypal_payments_partner_config_override_return_url',
+			admin_url( 'admin.php?page=wc-settings&tab=checkout&section=ppcp-gateway' )
+		);
+
+		/**
+		 * Filter the label of the "Return to your shop" button.
+		 * It's displayed on the very last page of the onboarding popup.
+		 */
+		$return_url_label = apply_filters(
+			'woocommerce_paypal_payments_partner_config_override_return_url_description',
+			__( 'Return to your shop.', 'woocommerce-paypal-payments' )
+		);
+
+		$capabilities         = array();
+		$first_party_features = array(
+			'PAYMENT',
+			'REFUND',
+			'ADVANCED_TRANSACTIONS_SEARCH',
+			'TRACKING_SHIPMENT_READWRITE',
+		);
+
+		if ( true === $use_subscriptions ) {
+			$capabilities[] = 'PAYPAL_WALLET_VAULTING_ADVANCED';
+		}
+
+		// Backwards compatibility. Keep those features in the legacy UI (null-value).
+		// Move this into the previous condition, once legacy code is removed.
+		if ( false !== $use_subscriptions ) {
+			$first_party_features[] = 'FUTURE_PAYMENT';
+			$first_party_features[] = 'VAULT';
+		}
+
+		if ( false === $use_subscriptions ) {
+			// Only use "ADVANCED_VAULTING" product for onboarding with subscriptions.
+			$products = array_filter(
+				$products,
+				static fn( $product ) => $product !== 'ADVANCED_VAULTING'
+			);
+		}
+
+		$payload = array(
+			'partner_config_override' => array(
+				'return_url'             => $return_url,
+				'return_url_description' => $return_url_label,
+				'show_add_credit_card'   => $use_card_payments,
+			),
+			'products'                => $products,
+			'capabilities'            => $capabilities,
+			'legal_consents'          => array(
+				array(
+					'type'    => 'SHARE_DATA_CONSENT',
+					'granted' => true,
 				),
-				'products'                => $this->products,
-				'legal_consents'          => array(
-					array(
-						'type'    => 'SHARE_DATA_CONSENT',
-						'granted' => true,
-					),
-				),
-				'operations'              => array(
-					array(
-						'operation'                  => 'API_INTEGRATION',
-						'api_integration_preference' => array(
-							'rest_api_integration' => array(
-								'integration_method'  => 'PAYPAL',
-								'integration_type'    => 'FIRST_PARTY',
-								'first_party_details' => array(
-									'features'     => array(
-										'PAYMENT',
-										'FUTURE_PAYMENT',
-										'REFUND',
-										'ADVANCED_TRANSACTIONS_SEARCH',
-										'VAULT',
-										'TRACKING_SHIPMENT_READWRITE',
-									),
-									'seller_nonce' => $this->nonce(),
-								),
+			),
+			'operations'              => array(
+				array(
+					'operation'                  => 'API_INTEGRATION',
+					'api_integration_preference' => array(
+						'rest_api_integration' => array(
+							'integration_method'  => 'PAYPAL',
+							'integration_type'    => 'FIRST_PARTY',
+							'first_party_details' => array(
+								'features'     => $first_party_features,
+								'seller_nonce' => $this->nonce(),
 							),
 						),
 					),
 				),
-			)
+			),
 		);
-	}
 
-	/**
-	 * Append the validation token to the return_url
-	 *
-	 * @param array  $data The referral data.
-	 * @param string $token The token to be appended.
-	 * @return array
-	 */
-	public function append_onboarding_token( array $data, string $token ): array {
-		$data['partner_config_override']['return_url'] =
-			add_query_arg( 'ppcpToken', $token, $data['partner_config_override']['return_url'] );
-		return $data;
+		/**
+		 * Filter the final partners referrals data collection.
+		 */
+		$payload = apply_filters( 'ppcp_partner_referrals_data', $payload );
+
+		// An empty array is not permitted.
+		if ( isset( $payload['capabilities'] ) && ! $payload['capabilities'] ) {
+			unset( $payload['capabilities'] );
+		}
+
+		// Add the nonce in the end, to maintain backwards compatibility of filters.
+		$payload['partner_config_override']['return_url'] = add_query_arg(
+			array( 'ppcpToken' => $onboarding_token ),
+			$payload['partner_config_override']['return_url']
+		);
+
+		return $payload;
 	}
 }
diff --git a/modules/ppcp-onboarding/src/Render/OnboardingRenderer.php b/modules/ppcp-onboarding/src/Render/OnboardingRenderer.php
index 081f1599b..13189fd77 100644
--- a/modules/ppcp-onboarding/src/Render/OnboardingRenderer.php
+++ b/modules/ppcp-onboarding/src/Render/OnboardingRenderer.php
@@ -103,12 +103,8 @@ class OnboardingRenderer {
 			'displayMode' => 'minibrowser',
 		);
 
-		$data = $this->partner_referrals_data
-			->with_products( $products )
-			->data();
-
 		$environment = $is_production ? 'production' : 'sandbox';
-		$product     = 'PPCP' === $data['products'][0] ? 'ppcp' : 'express_checkout';
+		$product     = strtolower( $products[0] ?? 'express_checkout' );
 		$cache_key   = $environment . '-' . $product;
 
 		$onboarding_url = new OnboardingUrl( $this->cache, $cache_key, get_current_user_id() );
@@ -122,8 +118,7 @@ class OnboardingRenderer {
 
 		$onboarding_url->init();
 
-		$data = $this->partner_referrals_data
-			->append_onboarding_token( $data, $onboarding_url->token() ?: '' );
+		$data = $this->partner_referrals_data->data( $products, $onboarding_url->token() ?: '' );
 
 		$url = $is_production ? $this->production_partner_referrals->signup_link( $data ) : $this->sandbox_partner_referrals->signup_link( $data );
 		$url = add_query_arg( $args, $url );
diff --git a/modules/ppcp-settings/resources/js/data/common/actions-thunk.js b/modules/ppcp-settings/resources/js/data/common/actions-thunk.js
index d49aa914a..f3f394bc0 100644
--- a/modules/ppcp-settings/resources/js/data/common/actions-thunk.js
+++ b/modules/ppcp-settings/resources/js/data/common/actions-thunk.js
@@ -68,10 +68,11 @@ export function sandboxOnboardingUrl() {
 /**
  * Side effect. Fetches the ISU-login URL for a production account.
  *
- * @param {string[]} products Which products/features to display in the ISU popup.
+ * @param {string[]} [products=[]] Which products/features to display in the ISU popup.
+ * @param {Object}   [options={}]  Options to customize the onboarding workflow.
  * @return {Function} The thunk function.
  */
-export function productionOnboardingUrl( products = [] ) {
+export function productionOnboardingUrl( products = [], options = {} ) {
 	return async () => {
 		try {
 			return apiFetch( {
@@ -80,6 +81,7 @@ export function productionOnboardingUrl( products = [] ) {
 				data: {
 					useSandbox: false,
 					products,
+					options,
 				},
 			} );
 		} catch ( e ) {
diff --git a/modules/ppcp-settings/resources/js/data/common/hooks.js b/modules/ppcp-settings/resources/js/data/common/hooks.js
index 6fe0a90f5..cb6dc9974 100644
--- a/modules/ppcp-settings/resources/js/data/common/hooks.js
+++ b/modules/ppcp-settings/resources/js/data/common/hooks.js
@@ -41,8 +41,6 @@ const useHooks = () => {
 	const { useTransient, usePersistent, dispatch, select } = useStoreData();
 	const {
 		persist,
-		sandboxOnboardingUrl,
-		productionOnboardingUrl,
 		authenticateWithCredentials,
 		authenticateWithOAuth,
 		startWebhookSimulation,
@@ -53,7 +51,6 @@ const useHooks = () => {
 	const [ activeModal, setActiveModal ] = useTransient( 'activeModal' );
 
 	// Persistent accessors.
-	const [ isSandboxMode, setSandboxMode ] = usePersistent( 'useSandbox' );
 	const [ isManualConnectionMode, setManualConnectionMode ] = usePersistent(
 		'useManualConnection'
 	);
@@ -71,16 +68,10 @@ const useHooks = () => {
 	return {
 		activeModal,
 		setActiveModal,
-		isSandboxMode,
-		setSandboxMode: ( state ) => {
-			return savePersistent( setSandboxMode, state );
-		},
 		isManualConnectionMode,
 		setManualConnectionMode: ( state ) => {
 			return savePersistent( setManualConnectionMode, state );
 		},
-		sandboxOnboardingUrl,
-		productionOnboardingUrl,
 		authenticateWithCredentials,
 		authenticateWithOAuth,
 		wooSettings,
@@ -105,13 +96,23 @@ export const useStore = () => {
 };
 
 export const useSandbox = () => {
-	const { isSandboxMode, setSandboxMode, sandboxOnboardingUrl } = useHooks();
+	const { dispatch, usePersistent } = useStoreData();
+	const [ isSandboxMode, setSandboxMode ] = usePersistent( 'useSandbox' );
+	const { sandboxOnboardingUrl, persist } = dispatch;
 
-	return { isSandboxMode, setSandboxMode, sandboxOnboardingUrl };
+	return {
+		isSandboxMode,
+		setSandboxMode: ( state ) => {
+			setSandboxMode( state );
+			return persist();
+		},
+		sandboxOnboardingUrl,
+	};
 };
 
 export const useProduction = () => {
-	const { productionOnboardingUrl } = useHooks();
+	const { dispatch } = useStoreData();
+	const { productionOnboardingUrl } = dispatch;
 
 	return { productionOnboardingUrl };
 };
diff --git a/modules/ppcp-settings/resources/js/data/onboarding/configuration.js b/modules/ppcp-settings/resources/js/data/onboarding/configuration.js
index 4b31689b5..280fee3af 100644
--- a/modules/ppcp-settings/resources/js/data/onboarding/configuration.js
+++ b/modules/ppcp-settings/resources/js/data/onboarding/configuration.js
@@ -24,3 +24,9 @@ export const PRODUCT_TYPES = {
 	PHYSICAL: 'physical',
 	SUBSCRIPTIONS: 'subscriptions',
 };
+
+export const PAYPAL_PRODUCTS = {
+	ACDC: 'PPCP',
+	BCDC: 'EXPRESS_CHECKOUT',
+	VAULTING: 'ADVANCED_VAULTING',
+};
diff --git a/modules/ppcp-settings/resources/js/data/onboarding/hooks.js b/modules/ppcp-settings/resources/js/data/onboarding/hooks.js
index 7c9ba1ee9..4d7549f5a 100644
--- a/modules/ppcp-settings/resources/js/data/onboarding/hooks.js
+++ b/modules/ppcp-settings/resources/js/data/onboarding/hooks.js
@@ -19,10 +19,6 @@ const useHooks = () => {
 
 	// Read-only flags and derived state.
 	const flags = useSelect( ( select ) => select( STORE_NAME ).flags(), [] );
-	const determineProducts = useSelect(
-		( select ) => select( STORE_NAME ).determineProducts(),
-		[]
-	);
 
 	// Transient accessors.
 	const [ isReady ] = useTransient( 'isReady' );
@@ -80,7 +76,6 @@ const useHooks = () => {
 			);
 			return savePersistent( setProducts, validProducts );
 		},
-		determineProducts,
 	};
 };
 
@@ -141,9 +136,9 @@ export const useNavigationState = () => {
 };
 
 export const useDetermineProducts = () => {
-	const { determineProducts } = useHooks();
-
-	return determineProducts;
+	return useSelect( ( select ) => {
+		return select( STORE_NAME ).determineProductsAndCaps();
+	}, [] );
 };
 
 export const useFlags = () => {
diff --git a/modules/ppcp-settings/resources/js/data/onboarding/selectors.js b/modules/ppcp-settings/resources/js/data/onboarding/selectors.js
index 9f3a7f35d..62579ac09 100644
--- a/modules/ppcp-settings/resources/js/data/onboarding/selectors.js
+++ b/modules/ppcp-settings/resources/js/data/onboarding/selectors.js
@@ -7,6 +7,8 @@
  * @file
  */
 
+import { PAYPAL_PRODUCTS, PRODUCT_TYPES } from './configuration';
+
 const EMPTY_OBJ = Object.freeze( {} );
 
 const getState = ( state ) => state || EMPTY_OBJ;
@@ -25,44 +27,71 @@ export const flags = ( state ) => {
 };
 
 /**
- * Returns the products that we use for the production login link in the last onboarding step.
+ * Returns details about products and capabilities to use for the production login link in
+ * the last onboarding step.
  *
  * This selector does not return state-values, but uses the state to derive the products-array
  * that should be returned.
  *
  * @param {{}} state
- * @return {string[]} The ISU products, based on choices made in the onboarding wizard.
+ * @return {{products:string[], options:{}}} The ISU products, based on choices made in the onboarding wizard.
  */
-export const determineProducts = ( state ) => {
-	const derivedProducts = [];
+export const determineProductsAndCaps = ( state ) => {
+	/**
+	 * An array of product-names that are used to build an onboarding URL via the
+	 * PartnerReferrals API. To avoid confusion with the "products" property from the
+	 * Redux store, this collection has a distinct name.
+	 *
+	 * On server-side, this value is referred to as "products" again.
+	 */
+	const apiModules = [];
 
-	const { isCasualSeller, areOptionalPaymentMethodsEnabled } =
+	/**
+	 * Internal options that are parsed by the PartnerReferrals class to customize
+	 * the API payload.
+	 */
+	const options = {
+		useSubscriptions: false,
+		useCardPayments: false,
+	};
+
+	const { isCasualSeller, areOptionalPaymentMethodsEnabled, products } =
 		persistentData( state );
 	const { canUseVaulting, canUseCardPayments } = flags( state );
+	const cardPaymentsEligibleAndSelected =
+		canUseCardPayments && areOptionalPaymentMethodsEnabled;
 
-	if ( ! canUseCardPayments || ! areOptionalPaymentMethodsEnabled ) {
+	if ( ! cardPaymentsEligibleAndSelected ) {
 		/**
 		 * Branch 1: Credit Card Payments not available.
 		 * The store uses the Express-checkout product.
 		 */
-		derivedProducts.push( 'EXPRESS_CHECKOUT' );
+		apiModules.push( PAYPAL_PRODUCTS.BCDC );
 	} else if ( isCasualSeller ) {
 		/**
 		 * Branch 2: Merchant has no business.
 		 * The store uses the Express-checkout product.
 		 */
-		derivedProducts.push( 'EXPRESS_CHECKOUT' );
+		apiModules.push( PAYPAL_PRODUCTS.BCDC );
 	} else {
 		/**
 		 * Branch 3: Merchant is business, and can use CC payments.
 		 * The store uses the advanced PPCP product.
+		 *
+		 * This is the only branch that can use subscriptions.
 		 */
-		derivedProducts.push( 'PPCP' );
+		apiModules.push( PAYPAL_PRODUCTS.ACDC );
+
+		if ( products?.includes( PRODUCT_TYPES.SUBSCRIPTIONS ) ) {
+			options.useSubscriptions = true;
+		}
+
+		if ( canUseVaulting ) {
+			apiModules.push( PAYPAL_PRODUCTS.VAULTING );
+		}
 	}
 
-	if ( canUseVaulting ) {
-		derivedProducts.push( 'ADVANCED_VAULTING' );
-	}
+	options.useCardPayments = cardPaymentsEligibleAndSelected;
 
-	return derivedProducts;
+	return { products: apiModules, options };
 };
diff --git a/modules/ppcp-settings/resources/js/data/onboarding/selectors.test.js b/modules/ppcp-settings/resources/js/data/onboarding/selectors.test.js
new file mode 100644
index 000000000..77febe32d
--- /dev/null
+++ b/modules/ppcp-settings/resources/js/data/onboarding/selectors.test.js
@@ -0,0 +1,181 @@
+import '@testing-library/jest-dom';
+
+import { PRODUCT_TYPES } from './configuration';
+import { determineProductsAndCaps } from './selectors';
+
+describe( 'determineProductsAndCaps selector [casual seller]', () => {
+	const testCases = [
+		{
+			name: 'should return EXPRESS_CHECKOUT when card payments are not available',
+			state: {
+				data: {
+					isCasualSeller: true,
+					areOptionalPaymentMethodsEnabled: true,
+				},
+				flags: { canUseCardPayments: false, canUseVaulting: false },
+			},
+			expected: {
+				products: [ 'EXPRESS_CHECKOUT' ],
+				options: { useSubscriptions: false, useCardPayments: false },
+			},
+		},
+		{
+			name: 'should return EXPRESS_CHECKOUT when optional payment methods are disabled',
+			state: {
+				data: {
+					isCasualSeller: true,
+					areOptionalPaymentMethodsEnabled: false,
+				},
+				flags: { canUseCardPayments: true, canUseVaulting: false },
+			},
+			expected: {
+				products: [ 'EXPRESS_CHECKOUT' ],
+				options: { useSubscriptions: false, useCardPayments: false },
+			},
+		},
+		{
+			name: 'should return EXPRESS_CHECKOUT for casual sellers with card payments',
+			state: {
+				data: {
+					isCasualSeller: true,
+					areOptionalPaymentMethodsEnabled: true,
+				},
+				flags: { canUseCardPayments: true, canUseVaulting: false },
+			},
+			expected: {
+				products: [ 'EXPRESS_CHECKOUT' ],
+				options: { useSubscriptions: false, useCardPayments: true },
+			},
+		},
+		{
+			name: 'should return EXPRESS_CHECKOUT and ADVANCED_VAULTING when card payments are not available but vaulting is',
+			state: {
+				data: {
+					isCasualSeller: true,
+					areOptionalPaymentMethodsEnabled: true,
+				},
+				flags: { canUseCardPayments: false, canUseVaulting: true },
+			},
+			expected: {
+				products: [ 'EXPRESS_CHECKOUT' ],
+				options: { useSubscriptions: false, useCardPayments: false },
+			},
+		},
+		{
+			name: 'should ignore SUBSCRIPTION product for casual sellers',
+			state: {
+				data: {
+					isCasualSeller: true,
+					areOptionalPaymentMethodsEnabled: true,
+					products: [ PRODUCT_TYPES.SUBSCRIPTIONS ],
+				},
+				flags: { canUseCardPayments: false, canUseVaulting: true },
+			},
+			expected: {
+				products: [ 'EXPRESS_CHECKOUT' ],
+				options: { useSubscriptions: false, useCardPayments: false },
+			},
+		},
+	];
+
+	test.each( testCases )( '$name', ( { state, expected } ) => {
+		const result = determineProductsAndCaps( state );
+		expect( result ).toEqual( expected );
+	} );
+} );
+
+describe( 'determineProductsAndCaps selector [business seller]', () => {
+	const testCases = [
+		{
+			name: 'should return EXPRESS_CHECKOUT when card payments are not available',
+			state: {
+				data: {
+					isCasualSeller: false,
+					areOptionalPaymentMethodsEnabled: true,
+				},
+				flags: { canUseCardPayments: false, canUseVaulting: false },
+			},
+			expected: {
+				products: [ 'EXPRESS_CHECKOUT' ],
+				options: { useSubscriptions: false, useCardPayments: false },
+			},
+		},
+		{
+			name: 'should return EXPRESS_CHECKOUT when optional payment methods are disabled',
+			state: {
+				data: {
+					isCasualSeller: false,
+					areOptionalPaymentMethodsEnabled: false,
+				},
+				flags: { canUseCardPayments: true, canUseVaulting: false },
+			},
+			expected: {
+				products: [ 'EXPRESS_CHECKOUT' ],
+				options: { useSubscriptions: false, useCardPayments: false },
+			},
+		},
+		{
+			name: 'should return PPCP for business merchants with card payments',
+			state: {
+				data: {
+					isCasualSeller: false,
+					areOptionalPaymentMethodsEnabled: true,
+				},
+				flags: { canUseCardPayments: true, canUseVaulting: false },
+			},
+			expected: {
+				products: [ 'PPCP' ],
+				options: { useSubscriptions: false, useCardPayments: true },
+			},
+		},
+		{
+			name: 'should include ADVANCED_VAULTING when vaulting is available',
+			state: {
+				data: {
+					isCasualSeller: false,
+					areOptionalPaymentMethodsEnabled: true,
+				},
+				flags: { canUseCardPayments: true, canUseVaulting: true },
+			},
+			expected: {
+				products: [ 'PPCP', 'ADVANCED_VAULTING' ],
+				options: { useSubscriptions: false, useCardPayments: true },
+			},
+		},
+		{
+			name: 'should return EXPRESS_CHECKOUT and ADVANCED_VAULTING when card payments are not available but vaulting is',
+			state: {
+				data: {
+					isCasualSeller: false,
+					areOptionalPaymentMethodsEnabled: true,
+					products: [ PRODUCT_TYPES.VIRTUAL ],
+				},
+				flags: { canUseCardPayments: false, canUseVaulting: true },
+			},
+			expected: {
+				products: [ 'EXPRESS_CHECKOUT' ],
+				options: { useSubscriptions: false, useCardPayments: false },
+			},
+		},
+		{
+			name: 'should enable the SUBSCRIPTIONS option when a business seller selects the subscriptions-product',
+			state: {
+				data: {
+					isCasualSeller: false,
+					areOptionalPaymentMethodsEnabled: true,
+					products: [ PRODUCT_TYPES.SUBSCRIPTIONS ],
+				},
+				flags: { canUseCardPayments: true, canUseVaulting: true },
+			},
+			expected: {
+				products: [ 'PPCP', 'ADVANCED_VAULTING' ],
+				options: { useSubscriptions: true, useCardPayments: true },
+			},
+		},
+	];
+
+	test.each( testCases )( '$name', ( { state, expected } ) => {
+		const result = determineProductsAndCaps( state );
+		expect( result ).toEqual( expected );
+	} );
+} );
diff --git a/modules/ppcp-settings/resources/js/hooks/useHandleConnections.js b/modules/ppcp-settings/resources/js/hooks/useHandleConnections.js
index e98345149..f74d6b8fe 100644
--- a/modules/ppcp-settings/resources/js/hooks/useHandleConnections.js
+++ b/modules/ppcp-settings/resources/js/hooks/useHandleConnections.js
@@ -30,7 +30,7 @@ const ACTIVITIES = {
 export const useHandleOnboardingButton = ( isSandbox ) => {
 	const { sandboxOnboardingUrl } = CommonHooks.useSandbox();
 	const { productionOnboardingUrl } = CommonHooks.useProduction();
-	const products = OnboardingHooks.useDetermineProducts();
+	const { products, options } = OnboardingHooks.useDetermineProducts();
 	const { startActivity } = CommonHooks.useBusyState();
 	const { authenticateWithOAuth } = CommonHooks.useAuthentication();
 	const [ onboardingUrl, setOnboardingUrl ] = useState( '' );
@@ -43,7 +43,7 @@ export const useHandleOnboardingButton = ( isSandbox ) => {
 			if ( isSandbox ) {
 				res = await sandboxOnboardingUrl();
 			} else {
-				res = await productionOnboardingUrl( products );
+				res = await productionOnboardingUrl( products, options );
 			}
 
 			if ( res.success && res.data ) {
diff --git a/modules/ppcp-settings/src/Endpoint/LoginLinkRestEndpoint.php b/modules/ppcp-settings/src/Endpoint/LoginLinkRestEndpoint.php
index b9972349f..3d6c45843 100644
--- a/modules/ppcp-settings/src/Endpoint/LoginLinkRestEndpoint.php
+++ b/modules/ppcp-settings/src/Endpoint/LoginLinkRestEndpoint.php
@@ -82,6 +82,16 @@ class LoginLinkRestEndpoint extends RestEndpoint {
 							return array_map( 'sanitize_text_field', $products );
 						},
 					),
+					'options'    => array(
+						'requires'          => false,
+						'type'              => 'array',
+						'items'             => array(
+							'type' => 'bool',
+						),
+						'sanitize_callback' => function ( $flags ) {
+							return array_map( array( $this, 'to_boolean' ), $flags );
+						},
+					),
 				),
 			)
 		);
@@ -97,9 +107,10 @@ class LoginLinkRestEndpoint extends RestEndpoint {
 	public function get_login_url( WP_REST_Request $request ) : WP_REST_Response {
 		$use_sandbox = $request->get_param( 'useSandbox' );
 		$products    = $request->get_param( 'products' );
+		$flags       = (array) $request->get_param( 'options' );
 
 		try {
-			$url = $this->url_generator->generate( $products, $use_sandbox );
+			$url = $this->url_generator->generate( $products, $flags, $use_sandbox );
 
 			return $this->return_success( $url );
 		} catch ( \Exception $e ) {
diff --git a/modules/ppcp-settings/src/Service/ConnectionUrlGenerator.php b/modules/ppcp-settings/src/Service/ConnectionUrlGenerator.php
index 279821bee..c3204ccf1 100644
--- a/modules/ppcp-settings/src/Service/ConnectionUrlGenerator.php
+++ b/modules/ppcp-settings/src/Service/ConnectionUrlGenerator.php
@@ -82,12 +82,13 @@ class ConnectionUrlGenerator {
 	 *
 	 * @param array $products    An array of product identifiers to include in the sign-up process.
 	 *                           These determine the PayPal onboarding experience.
+	 * @param array $flags       Onboarding choices that will customize the ISU payload.
 	 * @param bool  $use_sandbox Whether to generate a sandbox URL.
 	 *
 	 * @return string The generated PayPal onboarding URL.
 	 */
-	public function generate( array $products = array(), bool $use_sandbox = false ) : string {
-		$cache_key      = $this->cache_key( $products, $use_sandbox );
+	public function generate( array $products = array(), array $flags = array(), bool $use_sandbox = false ) : string {
+		$cache_key      = $this->cache_key( $products, $flags, $use_sandbox );
 		$user_id        = get_current_user_id();
 		$onboarding_url = $this->url_manager->get( $cache_key, $user_id );
 		$cached_url     = $this->try_get_from_cache( $onboarding_url, $cache_key );
@@ -100,7 +101,7 @@ class ConnectionUrlGenerator {
 
 		$this->logger->info( 'Generating onboarding URL for: ' . $cache_key );
 
-		$url = $this->generate_new_url( $use_sandbox, $products, $onboarding_url, $cache_key );
+		$url = $this->generate_new_url( $use_sandbox, $products, $flags, $onboarding_url, $cache_key );
 
 		if ( $url ) {
 			$this->persist_url( $onboarding_url, $url );
@@ -112,18 +113,28 @@ class ConnectionUrlGenerator {
 	/**
 	 * Generates a cache key from the environment and sorted product array.
 	 *
+	 * Q: Why do we cache the connection URL?
+	 * A: The URL is generated by a partner-referrals API, i.e. it requires a
+	 *    remote request; caching the response avoids unnecessary API calls.
+	 *
 	 * @param array $products    Product identifiers that are part of the cache key.
+	 * @param array $flags       Onboarding flags.
 	 * @param bool  $for_sandbox Whether the cache contains a sandbox URL.
 	 *
 	 * @return string The cache key, defining the product list and environment.
 	 */
-	protected function cache_key( array $products, bool $for_sandbox ) : string {
+	protected function cache_key( array $products, array $flags, bool $for_sandbox ) : string {
 		$environment = $for_sandbox ? 'sandbox' : 'production';
 
 		// Sort products alphabetically, to improve cache implementation.
 		sort( $products );
 
-		return $environment . '-' . implode( '-', $products );
+		// Extract the names of active flags.
+		$active_flags = array_keys( array_filter( $flags ) );
+
+		return strtolower(
+			$environment . '-' . implode( '-', $products ) . '-' . implode( '-', $active_flags )
+		);
 	}
 
 	/**
@@ -162,12 +173,13 @@ class ConnectionUrlGenerator {
 	 *
 	 * @param bool          $for_sandbox    Whether to generate a sandbox URL.
 	 * @param array         $products       The products array.
+	 * @param array         $flags          Onboarding flags.
 	 * @param OnboardingUrl $onboarding_url The OnboardingUrl object.
 	 * @param string        $cache_key      The cache key.
 	 *
 	 * @return string The generated URL or an empty string on failure.
 	 */
-	protected function generate_new_url( bool $for_sandbox, array $products, OnboardingUrl $onboarding_url, string $cache_key ) : string {
+	protected function generate_new_url( bool $for_sandbox, array $products, array $flags, OnboardingUrl $onboarding_url, string $cache_key ) : string {
 		$query_args = array( 'displayMode' => 'minibrowser' );
 		$onboarding_url->init();
 
@@ -179,7 +191,7 @@ class ConnectionUrlGenerator {
 			return '';
 		}
 
-		$data = $this->prepare_referral_data( $products, $onboarding_token );
+		$data = $this->prepare_referral_data( $products, $flags, $onboarding_token );
 
 		try {
 			$referral = $this->partner_referrals->get_value( $for_sandbox );
@@ -197,16 +209,18 @@ class ConnectionUrlGenerator {
 	 * Prepares the referral data.
 	 *
 	 * @param array  $products         The products array.
+	 * @param array  $flags            Onboarding flags.
 	 * @param string $onboarding_token The onboarding token.
 	 *
 	 * @return array The prepared referral data.
 	 */
-	protected function prepare_referral_data( array $products, string $onboarding_token ) : array {
-		$data = $this->referrals_data
-			->with_products( $products )
-			->data();
-
-		return $this->referrals_data->append_onboarding_token( $data, $onboarding_token );
+	protected function prepare_referral_data( array $products, array $flags, string $onboarding_token ) : array {
+		return $this->referrals_data->data(
+			$products,
+			$onboarding_token,
+			(bool) ( $flags['useSubscriptions'] ?? false ),
+			(bool) ( $flags['useCardPayments'] ?? false )
+		);
 	}
 
 	/**
diff --git a/tests/PHPUnit/ApiClient/Repository/PartnerReferralsDataTest.php b/tests/PHPUnit/ApiClient/Repository/PartnerReferralsDataTest.php
new file mode 100644
index 000000000..11bd0a138
--- /dev/null
+++ b/tests/PHPUnit/ApiClient/Repository/PartnerReferralsDataTest.php
@@ -0,0 +1,217 @@
+<?php
+declare( strict_types = 1 );
+
+namespace WooCommerce\PayPalCommerce\ApiClient\Repository;
+
+use Mockery;
+use WooCommerce\PayPalCommerce\TestCase;
+use WooCommerce\PayPalCommerce\ApiClient\Helper\DccApplies;
+use function Brain\Monkey\Functions\when;
+
+/**
+ * @group api
+ * @group onboarding
+ */
+class PartnerReferralsDataTest extends TestCase {
+	/**
+	 * Expected nonce that should appear in the payload.
+	 */
+	private const DEFAULT_NONCE = 'a1233wtergfsdt4365tzrshgfbaewa36AGa1233wtergfsdt4365tzrshgfbaewa36AG';
+
+	/**
+	 * Sample URL which is used to mock the `admin_url()` response, used to build the return URL.
+	 * Specifically, we want to verify the $path which is appended to the admin URL.
+	 */
+	private const ADMIN_URL = 'https://example.com/wp-admin/';
+
+	/**
+	 * A sample token that we add to the return URL.
+	 * We pass this const to the `->data()` method to ensure it's appended at the end of the
+	 * return URL as-is.
+	 */
+	private const TOKEN = 'SECURE_TOKEN';
+
+	/**
+	 * Expected return URL to see at in the payload, including the ppcpToken.
+	 */
+	private const RETURN_URL = 'https://example.com/wp-admin/admin.php?page=wc-settings&tab=checkout&section=ppcp-gateway&ppcpToken=SECURE_TOKEN';
+
+	private $testee;
+	private $dccApplies;
+
+	public function setUp() : void {
+		parent::setUp();
+
+		$this->dccApplies = Mockery::mock( DccApplies::class );
+		$this->testee     = new PartnerReferralsData( $this->dccApplies );
+
+		when( 'admin_url' )->alias( static fn( string $path ) => self::ADMIN_URL . $path );
+		when( 'add_query_arg' )->justReturn( self::RETURN_URL );
+	}
+
+	/**
+	 * Base structure of the API payload. Each test should modify the returned
+	 * value of the method to meet its expectations.
+	 *
+	 * This avoids repeating the full structure, while also highlighting the
+	 * specific changes that different params will generate.
+	 *
+	 * @return array
+	 */
+	private function getBaseExpectedArray() : array {
+		return [
+			'partner_config_override' => [
+				'return_url'             => self::RETURN_URL,
+				'return_url_description' => 'Return to your shop.',
+				'show_add_credit_card'   => true,
+			],
+			'legal_consents'          => [
+				[
+					'type'    => 'SHARE_DATA_CONSENT',
+					'granted' => true,
+				],
+			],
+			'operations'              => [
+				[
+					'operation'                  => 'API_INTEGRATION',
+					'api_integration_preference' => [
+						'rest_api_integration' => [
+							'integration_method'  => 'PAYPAL',
+							'integration_type'    => 'FIRST_PARTY',
+							'first_party_details' => [
+								'features'     => [
+									'PAYMENT',
+									'REFUND',
+									'ADVANCED_TRANSACTIONS_SEARCH',
+									'TRACKING_SHIPMENT_READWRITE',
+								],
+								'seller_nonce' => self::DEFAULT_NONCE,
+							],
+						],
+					],
+				],
+			],
+		];
+	}
+
+	/**
+	 * Data provider for testing flag combinations.
+	 *
+	 * @return array[] Test cases with [has_subscriptions, has_cards, expected_changes]
+	 */
+	public function flagCombinationsProvider() : array {
+		return [
+			'with subscriptions and cards' => [
+				true, // With subscription?
+				true, // With cards?
+				[
+					'capabilities'         => [ 'PAYPAL_WALLET_VAULTING_ADVANCED' ],
+					'show_add_credit_card' => true,
+					'has_vault_features'   => true,
+				],
+			],
+			'with subscriptions, no cards' => [
+				true,  // With subscription?
+				false, // With cards?
+				[
+					'capabilities'         => [ 'PAYPAL_WALLET_VAULTING_ADVANCED' ],
+					'show_add_credit_card' => false,
+					'has_vault_features'   => true,
+				],
+			],
+			'no subscriptions, with cards' => [
+				false, // With subscription?
+				true,  // With cards?
+				[
+					'show_add_credit_card' => true,
+					'has_vault_features'   => false,
+				],
+			],
+			'no subscriptions, no cards'   => [
+				false, // With subscription?
+				false, // With cards?
+				[
+					'show_add_credit_card' => false,
+					'has_vault_features'   => false,
+				],
+			],
+		];
+	}
+
+	/**
+	 * Ensure the default "products" are derived from the DccApplies response.
+	 */
+	public function testDefaultValues() : void {
+		/**
+		 * Case 1: The data() method gets no parameters, and the DccApplies check
+		 * returns TRUE. Onboarding payload should indicate "PPCP".
+		 */
+		$this->dccApplies->expects( 'for_country_currency' )->andReturn( true );
+		$result = $this->testee->data();
+		$this->assertEquals( [ 'PPCP' ], $result['products'] );
+
+		/**
+		 * Case 2: The data() method gets no parameters, and the DccApplies check
+		 * returns FALSE. Onboarding payload should indicate "EXPRESS_CHECKOUT".
+		 */
+		$this->dccApplies->expects( 'for_country_currency' )->andReturn( false );
+		$result = $this->testee->data();
+		$this->assertEquals( [ 'EXPRESS_CHECKOUT' ], $result['products'] );
+	}
+
+	/**
+	 * Ensure the generated API payload is stable and contains the expected values.
+	 *
+	 * The test only verifies the "products" and "token" arguments, as those are the
+	 * core params present in the legacy and new UI.
+	 */
+	public function testDataStructure() : void {
+		/**
+		 * Undefined subscription: Keep vaulting in first-party, but don't add the capability.
+		 */
+		$result = $this->testee->data( [ 'PPCP' ], self::TOKEN );
+		$this->dccApplies->shouldNotHaveReceived( 'for_country_currency' );
+
+		$expected = $this->getBaseExpectedArray();
+
+		$expected['products'] = [ 'PPCP' ];
+
+		$expected['operations'][0]['api_integration_preference']['rest_api_integration']['first_party_details']['features'][] = 'FUTURE_PAYMENT';
+		$expected['operations'][0]['api_integration_preference']['rest_api_integration']['first_party_details']['features'][] = 'VAULT';
+
+		$this->assertArrayNotHasKey( 'capabilities', $expected );
+		$this->assertEquals( $expected, $result );
+	}
+
+	/**
+	 * Test how different flag combinations affect the data structure.
+	 * Those flags are present in the new UI.
+	 *
+	 * @dataProvider flagCombinationsProvider
+	 */
+	public function testDataStructureWithFlags( bool $has_subscriptions, bool $has_cards, array $expected_changes ) : void {
+		$result   = $this->testee->data( [ 'PPCP' ], self::TOKEN, $has_subscriptions, $has_cards );
+		$expected = $this->getBaseExpectedArray();
+
+		$expected['products'] = [ 'PPCP' ];
+
+		if ( isset( $expected_changes['capabilities'] ) ) {
+			$expected['capabilities'] = $expected_changes['capabilities'];
+		} else {
+			$this->assertArrayNotHasKey( 'capabilities', $expected );
+		}
+
+		$expected['partner_config_override']['show_add_credit_card'] = $expected_changes['show_add_credit_card'];
+
+		if ( $expected_changes['has_vault_features'] ) {
+			$expected['operations'][0]['api_integration_preference']['rest_api_integration']['first_party_details']['features'][] = 'FUTURE_PAYMENT';
+			$expected['operations'][0]['api_integration_preference']['rest_api_integration']['first_party_details']['features'][] = 'VAULT';
+		} else {
+			// Double-check that the features are not present in our expected array
+			$this->assertNotContains( 'FUTURE_PAYMENT', $expected['operations'][0]['api_integration_preference']['rest_api_integration']['first_party_details']['features'] );
+			$this->assertNotContains( 'VAULT', $expected['operations'][0]['api_integration_preference']['rest_api_integration']['first_party_details']['features'] );
+		}
+
+		$this->assertEquals( $expected, $result );
+	}
+}