GA4 Audiences for Remarketing: Setup Guide and Best Practices

GA4 audiences are groups of users defined by the events, parameters, and behaviour you have collected in your property. Once built and published to Google Ads, they power remarketing campaigns, exclusion lists, and Smart Bidding signals. This guide shows you how to set them up correctly, which audiences are worth building first, and the mistakes that make them useless.

How GA4 Audiences Work

GA4 evaluates each user against your audience conditions in real time as new events arrive. When a user meets the conditions, they are added to the audience. They stay in the audience for a period you define (up to 540 days) and are removed when that window expires or when they no longer meet the conditions (for dynamic criteria).

For remarketing to work, your GA4 property must be linked to Google Ads and you must enable personalised advertising in the link settings. Once linked, any audience you publish is available in Google Ads within 24–48 hours — but it will not have data to show for campaigns until it reaches a minimum user threshold (typically 100 users for Display, 1,000 for Search).

The Audiences Worth Building First

Start with the audiences that are closest to revenue. These generate the highest returns in remarketing because the users already showed intent:

1. Cart Abandoners (Last 7 Days)

Users who triggered add_to_cart but did NOT trigger purchase within 7 days. This is your highest-intent, highest-priority audience.

Condition: Include users where event_name equals add_to_cart AND exclude users where event_name equals purchase. Set membership duration to 7 days.

2. Checkout Abandoners (Last 3 Days)

Users who triggered begin_checkout but not purchase. Shorter membership window (3 days) because checkout intent fades quickly and longer windows dilute the audience with users who are no longer shopping.

3. Past Buyers (Last 90 Days)

Users who triggered purchase at least once in the last 90 days. Use this audience for cross-sell and upsell campaigns, and as a seed list for Lookalike (Similar Audiences) targeting.

4. High-Value Buyers (Purchase Value > $X)

Users who triggered purchase with a value parameter above a threshold that represents your top 20% of customers. You need custom dimensions set up for this — the value parameter from your purchase event must be registered as a custom metric in GA4.

5. Product Page Viewers (No Purchase, Last 14 Days)

Users who viewed at least 2 product pages but did not purchase. A broad top-of-funnel remarketing pool. Less valuable than cart abandoners but much larger in volume.

6. All Purchasers (Exclusion List)

Create this audience to exclude from new-customer acquisition campaigns. Without it, you pay to reacquire customers who already bought — especially wasteful in Broad Match or Performance Max campaigns where Google’s targeting can pull in returning buyers.

How to Build Audiences in GA4

In GA4, go to Admin → Audiences → New audience.
Choose Create a custom audience (not a template — templates use session-based conditions that do not update in real time).
Set the Audience name clearly: Cart Abandoners — 7d is better than Audience 1.
Under Include users when, click Add new condition.
Select Events → choose the event name (e.g. add_to_cart).
To build the “did NOT purchase” condition, add a second condition group using Exclude users when → Event name equals purchase. Set the exclusion scope to Across all sessions if you want lifetime exclusion, or Within the same session for same-session logic only.
Set the Membership duration in days.
Click Save.

Publishing Audiences to Google Ads

Audiences are published automatically to all linked ad platforms as soon as you save them — you do not need to manually export or import. To confirm:

In Google Ads, go to Tools → Shared library → Audience manager.
Look for your audience under Your data sources → Google Analytics.
The audience will show a user count once it reaches the minimum threshold.

In Google Ads campaigns, add the audience under Audiences → Add audience segments. For remarketing campaigns, set the targeting setting to Targeting (not Observation) so the campaign only serves to audience members. For RLSA (Remarketing Lists for Search Ads), you can use Observation mode with a bid adjustment — you keep broad targeting but bid more for users who are also in your audience.

Audience Size and the Minimum Threshold Problem

Google Ads will not serve a remarketing campaign until the audience has at least 100 users (Display) or 1,000 users (Search). For many small stores, cart abandoner lists take weeks to reach these thresholds.

Options to work around this:

Broaden the membership window — extend from 7 to 30 days to accumulate more users faster. You lose recency precision but gain volume.
Combine audiences — in Google Ads, you can create an audience combination that merges Cart Abandoners + Checkout Abandoners into a single list, reaching the threshold sooner.
Use Similar Audiences on your Past Buyers list — if your Past Buyers list has enough users, Google generates a Similar Audiences list that you can target in acquisition campaigns while your remarketing lists grow.

Predictive Audiences

GA4 offers predictive audiences if your property meets the minimum training data requirements (typically 1,000 purchases from the past 28 days):

Likely 7-day purchasers — users predicted to make a purchase in the next 7 days based on their behaviour patterns.
Likely 7-day churning purchasers — past buyers who are predicted not to purchase again in the next 7 days (win-back campaigns).
Predicted top spenders — users predicted to spend the most in the next 28 days.

Predictive audiences are visible under Admin → Audiences → New audience → Predictive — but only if the ML model has enough data. For most stores under $1M annual revenue, these will not be available.

Common Mistakes with GA4 Remarketing Audiences

Not excluding past buyers from acquisition campaigns — you end up paying full acquisition cost for users who already converted.
Membership window too short — a 1-day cart abandoner list almost never reaches the minimum threshold for ad serving.
Remarketing to all site visitors without segmentation — showing the same ad to someone who bounced after 5 seconds and someone who spent 10 minutes on product pages is inefficient. Segment by intent.
Not checking GA4-Google Ads link is active — if the link breaks (e.g. after a GA4 property change), audiences stop updating silently. Check the link status quarterly in Admin → Google Ads Links.
Using session scope for the exclusion condition — using Within the same session for the purchase exclusion means users who buy and come back later still appear in your cart abandoner audience. Use Across all sessions for the exclusion.

Testing Your Audience Setup

After building an audience, verify it is collecting users correctly:

In GA4 Explore, create a free-form exploration.
Under Segments, apply your new audience as a segment.
Add event_name as a dimension and Event count as a metric.
Verify that the segment shows add_to_cart events but no purchase events (for cart abandoner audience).

This confirms the audience logic is working before you spend budget on a remarketing campaign targeting it. For the related GA4 custom events that feed into these audiences, make sure those events are verified first — a broken event means an empty audience.

Not Sure Your Audiences Are Set Up Correctly?

Broken events mean empty audiences mean wasted remarketing budget. We offer a free 20-minute tracking audit where we check your GA4 events and audience logic live.

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