diff --git a/plugins/woocommerce-admin/client/customize-store/assembler-hub/sidebar/sidebar-navigation-screen-typography.tsx b/plugins/woocommerce-admin/client/customize-store/assembler-hub/sidebar/sidebar-navigation-screen-typography.tsx
index e904cb922f43..2c64d1489076 100644
--- a/plugins/woocommerce-admin/client/customize-store/assembler-hub/sidebar/sidebar-navigation-screen-typography.tsx
+++ b/plugins/woocommerce-admin/client/customize-store/assembler-hub/sidebar/sidebar-navigation-screen-typography.tsx
@@ -9,7 +9,7 @@ import {
 	useContext,
 	useState,
 } from '@wordpress/element';
-import { dispatch, useSelect } from '@wordpress/data';
+import { useSelect } from '@wordpress/data';
 import { Link } from '@woocommerce/components';
 import { OPTIONS_STORE_NAME } from '@woocommerce/data';
 import { recordEvent } from '@woocommerce/tracks';
@@ -24,8 +24,9 @@ import { ADMIN_URL } from '~/utils/admin-settings';
 import { FontPairing } from './global-styles';
 import { CustomizeStoreContext } from '..';
 import { FlowType } from '~/customize-store/types';
+import { isIframe, sendMessageToParent } from '~/customize-store/utils';
 export const SidebarNavigationScreenTypography = () => {
-	const { context } = useContext( CustomizeStoreContext );
+	const { context, sendEvent } = useContext( CustomizeStoreContext );
 	const aiOnline = context.flowType === FlowType.AIOnline;
 	const isFontLibraryAvailable = context.isFontLibraryAvailable;
 
@@ -67,7 +68,7 @@ export const SidebarNavigationScreenTypography = () => {
 		upgradeNotice = '';
 	}
 
-	const OptIn = () => {
+	const optIn = () => {
 		recordEvent(
 			'customize_your_store_assembler_hub_opt_in_usage_tracking'
 		);
@@ -200,19 +201,17 @@ export const SidebarNavigationScreenTypography = () => {
 											{ __( 'Cancel', 'woocommerce' ) }
 										</Button>
 										<Button
-											onClick={ async () => {
-												await dispatch(
-													OPTIONS_STORE_NAME
-												).updateOptions( {
-													woocommerce_allow_tracking:
-														OptInDataSharing
-															? 'yes'
-															: 'no',
-												} );
-
-												OptIn();
-												closeModal();
-												window.location.href = `${ ADMIN_URL }admin.php?page=wc-admin&path=%2Fcustomize-store%2Fassembler-hub`;
+											onClick={ () => {
+												optIn();
+												if ( isIframe( window ) ) {
+													sendMessageToParent( {
+														type: 'INSTALL_FONTS',
+													} );
+												} else {
+													sendEvent(
+														'INSTALL_FONTS'
+													);
+												}
 											} }
 											variant="primary"
 											disabled={ ! OptInDataSharing }
diff --git a/plugins/woocommerce-admin/client/customize-store/design-without-ai/index.tsx b/plugins/woocommerce-admin/client/customize-store/design-without-ai/index.tsx
index e28b6e43d136..fc4e84d961c7 100644
--- a/plugins/woocommerce-admin/client/customize-store/design-without-ai/index.tsx
+++ b/plugins/woocommerce-admin/client/customize-store/design-without-ai/index.tsx
@@ -15,7 +15,7 @@ import {
 } from '../types';
 import { designWithNoAiStateMachineDefinition } from './state-machine';
 import { findComponentMeta } from '~/utils/xstate/find-component';
-import { AssembleHubLoader } from '../design-with-ai/pages';
+import { AssembleHubLoader } from './pages/ApiCallLoader';
 
 export type DesignWithoutAiComponent = typeof AssembleHubLoader;
 export type DesignWithoutAiComponentMeta = {
@@ -30,15 +30,18 @@ export const DesignWithNoAiController = ( {
 	sendEventToParent?: Sender< customizeStoreStateMachineEvents >;
 	parentContext?: customizeStoreStateMachineContext;
 } ) => {
-	const [ , , service ] = useMachine( designWithNoAiStateMachineDefinition, {
-		devTools: process.env.NODE_ENV === 'development',
-		parent: parentMachine,
-		context: {
-			...designWithNoAiStateMachineDefinition.context,
-			isFontLibraryAvailable:
-				parentContext?.isFontLibraryAvailable ?? false,
-		},
-	} );
+	const [ , send, service ] = useMachine(
+		designWithNoAiStateMachineDefinition,
+		{
+			devTools: process.env.NODE_ENV === 'development',
+			parent: parentMachine,
+			context: {
+				...designWithNoAiStateMachineDefinition.context,
+				isFontLibraryAvailable:
+					parentContext?.isFontLibraryAvailable ?? false,
+			},
+		}
+	);
 
 	// eslint-disable-next-line react-hooks/exhaustive-deps -- false positive due to function name match, this isn't from react std lib
 	const currentNodeMeta = useSelector( service, ( currentState ) =>
@@ -59,7 +62,11 @@ export const DesignWithNoAiController = ( {
 	return (
 		<>
 			<div className={ `woocommerce-design-without-ai__container` }>
-				{ CurrentComponent ? <CurrentComponent /> : <div /> }
+				{ CurrentComponent ? (
+					<CurrentComponent sendEvent={ send } />
+				) : (
+					<div />
+				) }
 			</div>
 		</>
 	);
diff --git a/plugins/woocommerce-admin/client/customize-store/design-without-ai/pages/ApiCallLoader.tsx b/plugins/woocommerce-admin/client/customize-store/design-without-ai/pages/ApiCallLoader.tsx
index 6a4f9ad139d5..49674500b436 100644
--- a/plugins/woocommerce-admin/client/customize-store/design-without-ai/pages/ApiCallLoader.tsx
+++ b/plugins/woocommerce-admin/client/customize-store/design-without-ai/pages/ApiCallLoader.tsx
@@ -17,6 +17,7 @@ import {
 	createAugmentedSteps,
 	onIframeLoad,
 } from '~/customize-store/utils';
+import { DesignWithoutAIStateMachineEvents } from '../state-machine';
 
 const loaderSteps = [
 	{
@@ -103,11 +104,21 @@ export const ApiCallLoader = () => {
 	);
 };
 
-const AssemblerHub = () => {
+type SendEventFn = ( event: DesignWithoutAIStateMachineEvents ) => void;
+
+const AssemblerHub = ( { sendEvent }: { sendEvent: SendEventFn } ) => {
 	const assemblerUrl = getNewPath( {}, '/customize-store/assembler-hub', {} );
 	const iframe = useRef< HTMLIFrameElement >( null );
 	const [ isVisible, setIsVisible ] = useState( false );
 
+	useEffect( () => {
+		window.addEventListener( 'message', ( event ) => {
+			if ( event.data?.type === 'INSTALL_FONTS' ) {
+				sendEvent( { type: 'INSTALL_FONTS' } );
+			}
+		} );
+	}, [ sendEvent ] );
+
 	return (
 		<iframe
 			ref={ iframe }
@@ -127,7 +138,11 @@ const AssemblerHub = () => {
 	);
 };
 
-export const AssembleHubLoader = () => {
+export const AssembleHubLoader = ( {
+	sendEvent,
+}: {
+	sendEvent: SendEventFn;
+} ) => {
 	// Show the last two steps of the loader so that the last frame is the shortest time possible
 	const augmentedSteps = createAugmentedSteps( loaderSteps.slice( -2 ), 10 );
 
@@ -160,7 +175,7 @@ export const AssembleHubLoader = () => {
 					progress={ progress || 0 }
 				/>
 			</Loader>
-			<AssemblerHub />
+			<AssemblerHub sendEvent={ sendEvent } />
 		</>
 	);
 };
diff --git a/plugins/woocommerce-admin/client/customize-store/design-without-ai/services.ts b/plugins/woocommerce-admin/client/customize-store/design-without-ai/services.ts
index 4b23307f2679..a630362bda7b 100644
--- a/plugins/woocommerce-admin/client/customize-store/design-without-ai/services.ts
+++ b/plugins/woocommerce-admin/client/customize-store/design-without-ai/services.ts
@@ -235,6 +235,17 @@ const createProducts = async () => {
 	}
 };
 
+export const enableTracking = async () => {
+	try {
+		await dispatch( OPTIONS_STORE_NAME ).updateOptions( {
+			woocommerce_allow_tracking: 'yes',
+		} );
+		window.wcTracks.isEnabled = true;
+	} catch ( error ) {
+		throw error;
+	}
+};
+
 export const services = {
 	assembleSite,
 	browserPopstateHandler,
@@ -242,4 +253,5 @@ export const services = {
 	createProducts,
 	installFontFamilies,
 	updateGlobalStylesWithDefaultValues,
+	enableTracking,
 };
diff --git a/plugins/woocommerce-admin/client/customize-store/design-without-ai/state-machine.tsx b/plugins/woocommerce-admin/client/customize-store/design-without-ai/state-machine.tsx
index 54bcbfaadda7..5d43a752480e 100644
--- a/plugins/woocommerce-admin/client/customize-store/design-without-ai/state-machine.tsx
+++ b/plugins/woocommerce-admin/client/customize-store/design-without-ai/state-machine.tsx
@@ -29,8 +29,49 @@ export const hasStepInUrl = (
 	);
 };
 
+export const hasFontInstallInUrl = () => {
+	const { path = '' } = getQuery() as { path: string };
+	const pathFragments = path.split( '/' );
+	return (
+		pathFragments[ 2 ] === 'design' &&
+		pathFragments[ 3 ] === 'install-fonts'
+	);
+};
+
+const installFontFamiliesState = {
+	initial: 'checkFontLibrary',
+	states: {
+		checkFontLibrary: {
+			always: [
+				{
+					cond: {
+						type: 'isFontLibraryAvailable',
+					},
+					target: 'pending',
+				},
+				{ target: 'success' },
+			],
+		},
+		pending: {
+			invoke: {
+				src: 'installFontFamilies',
+				onDone: {
+					target: 'success',
+				},
+				onError: {
+					actions: 'redirectToIntroWithError',
+				},
+			},
+		},
+		success: {
+			type: 'final',
+		},
+	},
+};
+
 export type DesignWithoutAIStateMachineEvents =
 	| { type: 'EXTERNAL_URL_UPDATE' }
+	| { type: 'INSTALL_FONTS' }
 	| { type: 'NO_AI_FLOW_ERROR'; payload: { hasError: boolean } };
 
 export const designWithNoAiStateMachineDefinition = createMachine(
@@ -49,6 +90,9 @@ export const designWithNoAiStateMachineDefinition = createMachine(
 			EXTERNAL_URL_UPDATE: {
 				target: 'navigate',
 			},
+			INSTALL_FONTS: {
+				target: 'installFontFamilies',
+			},
 		},
 		context: {
 			startLoadingTime: null,
@@ -62,6 +106,13 @@ export const designWithNoAiStateMachineDefinition = createMachine(
 		states: {
 			navigate: {
 				always: [
+					{
+						cond: {
+							type: 'hasFontInstallInUrl',
+							step: 'design',
+						},
+						target: 'installFontFamilies',
+					},
 					{
 						cond: {
 							type: 'hasStepInUrl',
@@ -71,6 +122,31 @@ export const designWithNoAiStateMachineDefinition = createMachine(
 					},
 				],
 			},
+			installFontFamilies: {
+				meta: {
+					component: ApiCallLoader,
+				},
+				initial: 'enableTracking',
+				states: {
+					enableTracking: {
+						invoke: {
+							src: 'enableTracking',
+							onDone: {
+								target: 'checkFontLibrary',
+							},
+						},
+					},
+					checkFontLibrary:
+						installFontFamiliesState.states.checkFontLibrary,
+					pending: installFontFamiliesState.states.pending,
+					success: {
+						type: 'final',
+					},
+				},
+				onDone: {
+					target: '#designWithoutAI.showAssembleHub',
+				},
+			},
 			preAssembleSite: {
 				initial: 'preApiCallLoader',
 				id: 'preAssembleSite',
@@ -141,31 +217,13 @@ export const designWithNoAiStateMachineDefinition = createMachine(
 								},
 							},
 							installFontFamilies: {
-								initial: 'checkFontLibrary',
+								initial: installFontFamiliesState.initial,
 								states: {
-									checkFontLibrary: {
-										always: [
-											{
-												cond: {
-													type: 'isFontLibraryAvailable',
-												},
-												target: 'pending',
-											},
-											{ target: 'success' },
-										],
-									},
-									pending: {
-										invoke: {
-											src: 'installFontFamilies',
-											onDone: {
-												target: 'success',
-											},
-											onError: {
-												actions:
-													'redirectToIntroWithError',
-											},
-										},
-									},
+									checkFontLibrary:
+										installFontFamiliesState.states
+											.checkFontLibrary,
+									pending:
+										installFontFamiliesState.states.pending,
 									success: {
 										type: 'final',
 									},
@@ -184,7 +242,6 @@ export const designWithNoAiStateMachineDefinition = createMachine(
 					component: AssembleHubLoader,
 				},
 				entry: [ 'redirectToAssemblerHub' ],
-				type: 'final',
 			},
 		},
 	},
@@ -194,6 +251,7 @@ export const designWithNoAiStateMachineDefinition = createMachine(
 		guards: {
 			hasStepInUrl,
 			isFontLibraryAvailable,
+			hasFontInstallInUrl,
 		},
 	}
 );
diff --git a/plugins/woocommerce-admin/client/customize-store/index.tsx b/plugins/woocommerce-admin/client/customize-store/index.tsx
index f2f1b19f09c6..1a6744f337ff 100644
--- a/plugins/woocommerce-admin/client/customize-store/index.tsx
+++ b/plugins/woocommerce-admin/client/customize-store/index.tsx
@@ -57,6 +57,7 @@ export type customizeStoreStateMachineEvents =
 	| transitionalEvents
 	| { type: 'AI_WIZARD_CLOSED_BEFORE_COMPLETION'; payload: { step: string } }
 	| { type: 'EXTERNAL_URL_UPDATE' }
+	| { type: 'INSTALL_FONTS' }
 	| { type: 'NO_AI_FLOW_ERROR'; payload: { hasError: boolean } }
 	| { type: 'IS_FONT_LIBRARY_AVAILABLE'; payload: boolean };
 
@@ -202,6 +203,9 @@ export const customizeStoreStateMachineDefinition = createMachine( {
 				{ type: 'updateQueryStep', step: 'intro' },
 			],
 		},
+		INSTALL_FONTS: {
+			target: 'designWithoutAi.installFonts',
+		},
 	},
 	states: {
 		setFlags: {
@@ -365,6 +369,18 @@ export const customizeStoreStateMachineDefinition = createMachine( {
 						component: DesignWithoutAi,
 					},
 				},
+				// This state is used to install fonts and then redirect to the assembler hub.
+				installFonts: {
+					entry: [
+						{
+							type: 'updateQueryStep',
+							step: 'design/install-fonts',
+						},
+					],
+					meta: {
+						component: DesignWithoutAi,
+					},
+				},
 			},
 		},
 		designWithAi: {
diff --git a/plugins/woocommerce/changelog/45580-45476-cys-on-core-make-sure-the-pre-loader-is-triggered-right-after-the-user-clicks-on-the-opt-in-modal b/plugins/woocommerce/changelog/45580-45476-cys-on-core-make-sure-the-pre-loader-is-triggered-right-after-the-user-clicks-on-the-opt-in-modal
new file mode 100644
index 000000000000..744a611b0e32
--- /dev/null
+++ b/plugins/woocommerce/changelog/45580-45476-cys-on-core-make-sure-the-pre-loader-is-triggered-right-after-the-user-clicks-on-the-opt-in-modal
@@ -0,0 +1,4 @@
+Significance: minor
+Type: fix
+
+CYS - Core: install font when user clicks opt-in
\ No newline at end of file