diff --git a/libs/@guardian/libs/src/consent-management-platform/mergeUserConsent.ts b/libs/@guardian/libs/src/consent-management-platform/mergeUserConsent.ts
new file mode 100644
index 000000000..921b70fb7
--- /dev/null
+++ b/libs/@guardian/libs/src/consent-management-platform/mergeUserConsent.ts
@@ -0,0 +1,27 @@
+import { getCookie } from '../cookies/getCookie';
+import { PROPERTY_ID_MAIN, PROPERTY_ID_SUPPORT } from './lib/sourcepointConfig';
+import type { SPUserConsent } from './types/tcfv2';
+
+// https://sourcepoint-public-api.readme.io/reference/post_consent-v3-siteid-tcstring
+
+export const mergeUserConsent = () => {
+	const consentUUID = getCookie({ name: 'consentUUID' });
+	const url = `https://cdn.privacy-mgmt.com/consent/tcfv2/consent/v3/${PROPERTY_ID_SUPPORT}/tcstring?consentUUID=${consentUUID}`;
+	const spUserConsentString = localStorage.getItem(
+		`_sp_user_consent_${PROPERTY_ID_MAIN}`,
+	);
+	const userConsent = JSON.parse(spUserConsentString ?? '{}') as SPUserConsent;
+
+	fetch(url, {
+		method: 'POST',
+		headers: {
+			Accept: 'application/json',
+			'Content-Type': 'application/json',
+		},
+		body: JSON.stringify({
+			euconsent: userConsent.gdpr?.euconsent,
+		}),
+	}).catch((error) => {
+		console.error('Error:', error);
+	});
+};
diff --git a/libs/@guardian/libs/src/consent-management-platform/sourcepoint.ts b/libs/@guardian/libs/src/consent-management-platform/sourcepoint.ts
index 65556cd4b..eb550f0e1 100644
--- a/libs/@guardian/libs/src/consent-management-platform/sourcepoint.ts
+++ b/libs/@guardian/libs/src/consent-management-platform/sourcepoint.ts
@@ -11,6 +11,7 @@ import {
 	PROPERTY_ID_SUPPORT,
 	SourcePointChoiceTypes,
 } from './lib/sourcepointConfig';
+import { mergeUserConsent } from './mergeUserConsent';
 import { invokeCallbacks } from './onConsentChange';
 import { stub } from './stub';
 import type { ConsentFramework } from './types';
@@ -95,6 +96,10 @@ export const init = (
 	const isFeatureFlagEnabled = window.location.search.includes('CMP_COP');
 	const isMainSite = window.location.search.includes('CMP_MAIN');
 
+	if (!isMainSite) {
+		mergeUserConsent();
+	}
+
 	log('cmp', `framework: ${framework}`);
 	log('cmp', `frameworkMessageType: ${frameworkMessageType}`);
 
diff --git a/libs/@guardian/libs/src/consent-management-platform/types/tcfv2/index.ts b/libs/@guardian/libs/src/consent-management-platform/types/tcfv2/index.ts
index efb8ed173..a1d94d45e 100644
--- a/libs/@guardian/libs/src/consent-management-platform/types/tcfv2/index.ts
+++ b/libs/@guardian/libs/src/consent-management-platform/types/tcfv2/index.ts
@@ -26,3 +26,9 @@ export type TCPingStatusCode =
 	| 'visible'
 	| 'hidden'
 	| 'disabled';
+
+export interface SPUserConsent {
+	gdpr?: {
+		euconsent?: string;
+	};
+}