How Can Google Ads Utilize Audiences from Google Analytics When Linked?

What changes when Google Ads and Google Analytics are linked (and why it matters for audiences)

When you link Google Ads to Google Analytics 4 (GA4), you’re not just “connecting reports.” You’re creating a pipeline where GA4 can continuously share audiences (and key event-based conversions) into Google Ads so you can target, exclude, and guide automation using what people actually did on your site or in your app.

In practical terms, this is how you turn behavioral data—like “viewed pricing page,” “started checkout,” “watched a product video,” or “spent 90+ seconds on a category page”—into actionable audience segments that can influence bids, reach, and creative decisions across Search, Display, YouTube, and automated campaign types.

How GA4 audiences become usable in Google Ads

Once the link is active and audience sharing is allowed, GA4 audiences you build (for example, “All visitors,” “High-intent visitors,” “Cart abandoners,” “Past purchasers,” “Lead form starters,” “Users who viewed 3+ pages,” and so on) are exported to Google Ads as first-party audience segments (often treated as “your data”). From that point, you can use them the same way you’d use other first-party lists: to target, observe, exclude, or feed into automation as signals.

One important nuance: this export is ongoing. You’re not doing a one-time import. As users qualify for the audience in GA4, the matching list in Google Ads updates as well—assuming your configuration allows the data to be used for ads personalization and remarketing.

The “must-have” requirements (most audience issues come from these)

Linking accounts is necessary, but it’s not sufficient. For GA4 audiences to actually populate and become usable for advertising, you typically need a clean combination of permissions, data collection settings, and ads personalization eligibility.

• Correct linking and access: The Ads account must be linked to the correct GA4 property, and the people setting this up need admin-level access in Google Ads and appropriate roles in GA4. If you expect to create Analytics audiences from within Google Ads, the linked-user role in GA4 must be high enough (for example, Marketer/Editor/Admin, depending on your setup).
• Personalized advertising enabled on the link: The link includes a setting that allows sharing for ads personalization. If that’s off, audiences may exist in GA4 but won’t be eligible to export for targeting.
• Signals and/or user-provided data collection enabled: For many GA4 properties (especially those created after 2019), remarketing audiences require Google signals and/or user-provided data collection to be enabled to properly populate in Google Ads. Practically, this is what helps maintain reach when cookies/identifiers are limited.
• Data collection acknowledgment completed: GA4 includes an acknowledgment step in its data collection settings that can block downstream sharing until completed.

If any of the above is missing, you’ll usually see one of two symptoms: audiences never appear in Google Ads, or they appear but remain too small/at zero for far longer than expected.

Exactly how Google Ads can use Analytics audiences after linking

Once your GA4 audiences are flowing into Google Ads, your advantage isn’t just “remarketing.” The real ROI lift comes from using audiences strategically: as precision targeting where it’s appropriate, as exclusions to prevent waste, and as signals to guide automated bidding and automated campaign types toward the users most likely to convert.

1) Remarketing and re-engagement across channels

The most straightforward use is classic re-engagement: showing ads to people who already interacted with your business. But the winning approach is to segment by intent and funnel stage rather than relying on a single “All Visitors” list.

For example, instead of one catch-all remarketing list, you get far better control by splitting audiences into behavior-based tiers—like “product viewers,” “pricing page visitors,” “checkout starters,” “returning visitors,” and “past converters.” This allows you to tailor messaging, offers, and frequency expectations to where the user is in the decision process.

Also, don’t overlook suppression. Excluding “recent purchasers” (or “qualified leads already handed off”) often improves ROI faster than any new targeting tactic because it immediately reduces wasted impressions and clicks.

2) Search campaigns: Observation vs. Targeting (and when to use each)

In Search, audiences can be applied in two fundamentally different ways: Observation (you still target everyone via keywords, but you can analyze and adjust for audience performance) or Targeting (you restrict the ad group/campaign to only users in the audience).

In most mature accounts, Observation is the default best practice for core non-brand Search because it preserves volume while giving you insight into how different audiences perform. This is where GA4 audiences become extremely valuable: you can see whether “engaged users” or “pricing page visitors” convert at higher rates, and then make budget, bidding, or creative decisions accordingly.

Targeting tends to be best reserved for dedicated “remarketing-only” Search structures (for example, a separate campaign meant specifically for past visitors with tailored ad copy). This can work well when you need strict control or very specific messaging, but it’s easy to starve campaigns of volume if lists are small.

3) Performance Max: using Analytics audiences as audience signals (guidance, not a restriction)

For Performance Max, GA4 audiences are typically most powerful as audience signals. Signals help guide the system toward the right starting point for optimization—especially in the learning phase or when you’re launching into a new product category. The key expectation to set internally is that audience signals are directional: the system can still show ads outside your signals if it predicts better conversion likelihood.

In practice, this means your GA4 audiences should be built to describe real customer intent (not vanity segments). Think “users who viewed a specific service page,” “users who started an application,” or “users who spent time in the configurator,” rather than broad, low-intent audiences.

4) Building audiences directly in Google Ads using Analytics data (when you want speed)

When linked correctly, Google Ads can let qualified users create Analytics audiences from within the Google Ads interface. This is especially helpful for teams that live primarily in Google Ads and want to rapidly spin up a new segment without switching tools—just be mindful that the underlying logic still depends on what GA4 is collecting and what’s eligible for ads personalization.

Maximizing ROI safely: privacy, eligibility rules, and a practical troubleshooting flow

Privacy and consent: why audiences sometimes “shrink” overnight

Audience performance and size can change dramatically based on consent and ads personalization eligibility. If consent signals indicate that ads personalization or ad user data is denied, remarketing and certain personalization-dependent features won’t receive data the same way. In the real world, that can look like lists stalling, shrinking, or failing to qualify users at the rate you expect—especially after a consent banner change, tag change, or region-based consent rollout.

Additionally, GA4 allows you to exclude specific events or user-scoped custom dimensions from ads personalization. That’s a great governance feature when you want to keep some data strictly for measurement. However, it comes with a direct advertising tradeoff: if an audience is built using excluded data, that audience may remain usable inside Analytics but become ineligible for export to advertising destinations.

Finally, sensitive-category rules can restrict what audience types you’re allowed to use for personalization in certain verticals. If you operate in a regulated or sensitive interest space, build your audience strategy expecting constraints, and confirm eligibility before designing campaigns that depend on customer lists or highly specific remarketing logic.

When GA4 audiences don’t show up in Google Ads (or show up but stay empty)

If you want a fast, systematic way to diagnose this, run this checklist in order. It’s the same sequence my team uses because it finds the root cause quickly without guesswork.

• Confirm you linked the correct entities: right GA4 property → right Google Ads account (and not a different client, different property, or an old test property).
• Allow time for propagation: even after everything is correct, it can take hours for audiences to appear and begin populating.
• Verify link settings for sharing: ensure the link has audience sharing / personalized advertising enabled so audiences are eligible to export.
• Confirm GA4 data collection prerequisites: data collection acknowledgment completed; Google signals and/or user-provided data collection enabled where required.
• Check consent/ads personalization restrictions: if consent mode (or your consent framework) is denying ad_user_data and/or ad_personalization, remarketing won’t behave as expected.
• If you use a manager account: ensure the manager is configured as the audience manager for the child accounts that need to use the lists.

Audience-building tips that consistently improve performance

After 15+ years managing accounts of all sizes, I can tell you most “audience strategies” fail because they’re too broad, too vague, or too slow to act on. Your goal is to create segments that map to a decision point and a message.

Start with a small set of high-signal audiences: bottom-funnel intent (pricing/checkout/application), product/category engagement (specific pages or on-site actions), and converter-based segments (past purchasers/leads) for upsell and for suppression. Then layer recency. A “last 7 days” segment behaves nothing like a “last 90 days” segment, and your bids, creative, and frequency tolerance shouldn’t be the same either.

Finally, treat audiences as a measurement asset, not just a targeting lever. Even when you don’t restrict traffic with Targeting, running Observation on your best GA4 audiences is one of the fastest ways to identify which parts of your existing traffic are actually profitable—and where your budget is quietly leaking ROI.

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Once Google Analytics 4 is linked to Google Ads, the audiences you build in GA4 (from broad segments like “All users” to intent-based groups like product viewers, cart abandoners, or recent purchasers) can continuously sync into Google Ads as first-party “your data” segments, so you can use them for remarketing, exclusions, observation layers in Search, or as audience signals in Performance Max—assuming key settings like ads personalization, Signals/user-provided data, and consent are correctly configured. If you want a practical way to stay on top of that ongoing audience flow (and catch issues like lists not populating, shrinking due to consent changes, or being applied in the wrong mode), Blobr connects to your Google Ads account and runs specialized AI agents that monitor performance and surface clear, prioritized actions—so your GA4 audiences and targeting strategy stay aligned without having to manually audit everything each week.