Before you can run a retargeting campaign, Google Ads needs to know who to show ads to. That list comes from GA4. This article covers creating the right audiences from Growth Hub events, then linking GA4 to Google Ads so those audiences are available in your campaigns.

This is a one-time setup. Once your audiences are created and sharing is enabled, you do not need to repeat these steps for future campaigns.

In this article

Create GA4 audiences based on Growth Hub events.
Understand membership duration and why audience size matters.
Link GA4 to Google Ads and enable personalized advertising.
Enable Google Signals for cross-device remarketing.
Verify your audiences are visible in Google Ads.

Prerequisites

GA4 and GTM set up. Growth Hub events must be flowing into GA4 before you can create audiences from them.
GA4 admin access. You need Editor or Administrator permissions in your GA4 property.
Google Ads account. You need an active Google Ads account to link to GA4.

Overview

GA4 audiences are lists of users who met specific conditions on your website. You define the conditions using event names, and GA4 starts adding users to the list immediately after you create it. It does not backfill historical users.

For retargeting, you build audiences based on intent signals from the booking funnel, then exclude users who have already converted, so you are not wasting ad spend on people who have already booked.

Audiences do not backfill. If you create a begin_checkout audience today, only users who trigger begin_checkout after today will join it. This is why creating audiences early matters. A new audience for a low-traffic site may take weeks to reach the minimum size Google requires before ads can serve.

Step 1: Create your audiences in GA4

Create each audience in GA4 under Admin > Audiences. Select New Audience, then Custom Audience to set your own event conditions.

Audience 1: Viewed a resource, did not purchase

This is your broadest audience. It catches everyone who viewed a space on your storefront but did not book. Use it for awareness-style retargeting ads.

Include users when: event_name = view_item
Exclude users permanently when: event_name = purchase
Membership duration: 30 days

Why 30 days? Coworking decisions are often made within a few weeks. 30 days is long enough to build audience scale but short enough that the message is still relevant. Adjust based on your own data once the campaign has run.

Audience 2: Started checkout, did not purchase

This is your highest-intent audience. These visitors selected a space and began the payment process. Use it for direct, conversion-focused messages.

Include users when: event_name = begin_checkout
Exclude users permanently when: event_name = purchase
Membership duration: 7 to 14 days

Why a shorter window? Checkout intent drops off quickly. Someone who started booking 3 weeks ago has likely made a decision by now. A 7 to 14-day window keeps the audience focused on recent, high-intent visitors.

Audience 3 (optional): Submitted a lead, did not purchase

Add this audience once the first 2 are running. It catches visitors who submitted a booking request or inquiry but did not complete an online booking.

Include users when: event_name = generate_lead
Exclude users permanently when: event_name = purchase
Membership duration: 14 to 30 days

Step 2: Link GA4 to Google Ads

Linking the 2 platforms allows GA4 to share audiences and conversions with Google Ads. Do this in GA4, not in Google Ads.

In GA4, go to Admin (bottom left).
Under Product Links, select Google Ads Links.
Click Link.
Select your Google Ads account from the list.
Click Next.
Turn on Enable Personalized Advertising. This is required to transfer audiences to Google Ads for retargeting.
Click Submit.

Enable Personalized Advertising is required. Without this toggle turned on, GA4 audiences will not be available in Google Ads for retargeting. This is the most common reason audiences do not appear in Google Ads after linking.

Step 3: Enable Google signals

Google Signals allows GA4 to build remarketing audiences using signed-in Google user data across devices. This is required for remarketing to work correctly.

In GA4, go to Admin (bottom left).
Under Data Settings, select Data Collection.
Turn on Google Signals Data Collection.

Step 4: Verify audiences are visible in Google Ads

After linking, confirm your GA4 audiences have transferred to Google Ads. Allow up to 24 hours after linking before checking.

Go to Google Ads.
Go to Tools and Settings > Shared Library > Audience Manager.
Open the Your Data Segments tab.
Look for your GA4 audiences by name (for example, 'view_item no purchase').

Audience size will initially appear too small. This is expected. New audiences start empty and populate as users trigger the events you defined. Ads will not serve until the audience reaches the minimum size Google requires (at least 100 active users in the last 30 days for Display campaigns). This can take days or weeks, depending on your traffic volume.

Best practices

Create all audiences before you plan to launch. The earlier you create them, the more users will have accumulated by launch day. Create them now, even if you are not ready to run a campaign.
Use permanent exclusions for purchase. Setting the purchase exclusion to permanent means a user who converts is removed from the audience and never added back. This prevents showing conversion-focused ads to people who have already booked.
Name audiences clearly. Use names like "GH – view_item – no purchase" to easily identify them in Google Ads. Unclear names lead to targeting errors when setting up campaigns.
Launch view_item and begin_checkout audiences at the same time. view_item will build faster and give you something to target while begin_checkout reaches the minimum size.

Frequently asked questions

My GA4 audiences are not appearing in Google Ads. What should I check?

Check 3 things in order:

The Google Ads link in GA4 shows as Completed under Product Links > Google Ads Links.
Enable Personalized Advertising was turned on when you created the link.
At least 24 hours have passed since linking.

If all 3 are confirmed and audiences are still not visible, remove the link and re-create it with Personalized Advertising turned on.

How long until my audience is large enough to serve ads?

It depends entirely on your traffic volume. Google requires at least 100 active users in the last 30 days for Display campaigns. For a small operator with 200 to 500 monthly visitors, a view_item audience may take 2 to 4 weeks to reach a minimum size. A begin_checkout audience will take longer because fewer visitors reach that step.

Can I use the same audience in multiple campaigns?

Yes. Once an audience exists in Google Ads, you can use it in as many campaigns as you want. There is no limit on how many campaigns reference the same audience segment.

Build Retargeting Audiences in GA4 Using Growth Hub Events (Step 1)