GA4 for Paid Media: What You Actually Need to Track

GA4 has a reputation problem. Since Google replaced Universal Analytics with it in 2023, the most common reaction from business owners has been some variation of: it's confusing, the reports don't show what I need, and I have no idea whether it's set up correctly.

That reaction is understandable. GA4 is a fundamentally different platform from what came before — built around events rather than sessions, with a reporting interface that takes genuine getting used to. And the documentation, while extensive, isn't always written for people who just want to know whether their ads are working.

The good news is that for paid media purposes, you don't need to master every corner of GA4. You need a relatively small set of things configured correctly, a clear understanding of which reports to look at, and confidence that what you're measuring actually reflects what's happening in your business.

This guide covers exactly that — no unnecessary complexity, just the parts of GA4 that matter for running and evaluating paid campaigns.

Why GA4 matters for paid media specifically

Before getting into the setup, it's worth understanding why GA4 matters beyond just having a website analytics tool.

The paid media platforms — Google Ads, Meta, Microsoft Ads — each have their own native tracking and reporting. Google Ads tells you how many conversions it recorded. Meta tells you how many purchases it drove. But these figures are platform-reported, meaning each platform takes as much credit as its attribution model allows. They're often inflated, always self-serving to some degree, and frequently contradictory with each other.

GA4 is your independent source of truth. It sits on your website, tracking what visitors actually do regardless of where they came from. When configured correctly, it tells you which channels are genuinely driving conversions — not just which ones are claiming credit for them.

It also feeds directly back into Google Ads. Conversions imported from GA4 into Google Ads power Smart Bidding — which means a poorly configured GA4 setup doesn't just give you bad data, it actively causes your campaigns to optimise in the wrong direction.

Step one: make sure the GA4 tag is installed correctly

This sounds basic, but it's worth verifying — especially if GA4 was set up by a web developer or a previous agency rather than someone with a paid media background.

GA4 should be implemented via Google Tag Manager wherever possible. GTM gives you a central place to manage all your tracking tags — GA4, Google Ads, Meta Pixel, and any others — without requiring a developer every time something needs to change.

To verify your tag is firing correctly, install the GA4 DebugView or use the Google Tag Assistant Chrome extension. Visit your website and confirm that a page_view event is being sent to GA4 on each page load. If you're seeing duplicate page views, or no data at all, there's a tag configuration issue that needs resolving before anything else.

Also confirm you're sending data to the correct GA4 property. It's more common than you'd think for businesses to have multiple properties set up — often a legacy one and a newer one — with the tag pointing at the wrong one.

The events that actually matter

GA4 is built around an event-based data model. Everything that happens on your website — page views, button clicks, form submissions, purchases — is recorded as an event. For paid media, the events worth focusing on fall into two categories:

Primary conversion events

These are the actions that directly reflect a business outcome — a lead generated, a sale completed, an enquiry submitted. They're the events you should be importing into Google Ads and treating as conversion goals.

• Purchase — for e-commerce, this should fire on the order confirmation page with the transaction value passed through dynamically
• Form submission / generate_lead — for lead generation businesses, firing on the thank-you page after a form is completed
• Phone call clicks — if calls are a meaningful conversion route for your business, tracking click-to-call events is worth configuring
• Booking completions — for service businesses using third-party booking tools, this may require additional configuration via GTM

Secondary engagement events

These don't directly indicate a sale or lead, but provide useful context about user behaviour and funnel progression. They're particularly valuable for diagnosing where people are dropping off.

• add_to_cart and begin_checkout — for e-commerce, these show funnel progression and help identify where drop-off is occurring
• Scroll depth — useful for understanding whether people are actually reading your landing page content or bouncing immediately
• Key page views — product pages, pricing pages, contact pages — which indicate meaningful engagement even without a conversion

Marking the right events as conversions

In GA4, any event can be marked as a conversion — but that doesn't mean all of them should be. This is one of the most consequential configuration decisions you'll make, particularly if you're importing GA4 conversions into Google Ads.

The principle is straightforward: only mark events as conversions if they directly represent a business outcome. Page views, scroll events, and session starts should not be marked as conversions. If they are, Google Ads' Smart Bidding will optimise towards generating page views — which is cheap and easy, and completely useless.

In Google Ads specifically, there's a further distinction between primary and secondary conversions. Primary conversions are used to inform bidding. Secondary conversions are tracked for reporting purposes only. Make sure only your true business outcomes — purchases, leads, bookings — are set as primary. Everything else should be secondary or excluded entirely from your Google Ads conversion import.

A common mistake is importing all GA4 conversions into Google Ads without reviewing what's in that list. The result is Smart Bidding optimising towards a mix of real conversions and low-value engagement events — which dilutes performance in ways that can be very difficult to diagnose.

Linking GA4 to Google Ads — and why it matters

Linking your GA4 property to your Google Ads account is a straightforward process done through the Admin settings in GA4, but the impact is significant.

Once linked, you can import GA4 conversion events directly into Google Ads, which is where they'll be used to power bidding. You'll also unlock GA4 audience segments in Google Ads — meaning you can create remarketing audiences based on specific behaviours (users who viewed a product but didn't purchase, users who started a form but didn't complete it) and use those audiences in your campaigns.

The link also enables richer reporting in GA4 — you'll be able to see Google Ads cost data alongside your GA4 behaviour data, which makes it easier to evaluate campaign performance in a single view without toggling between platforms.

One important note: auto-tagging must be enabled in Google Ads for the link to work correctly. Auto-tagging appends a GCLID parameter to your ad URLs, which is how GA4 identifies traffic that came from a specific Google Ads click. If it's turned off, GA4 will attribute that traffic to organic search instead, making your Google Ads performance appear worse than it actually is.

The GA4 reports that are actually useful for paid media

GA4's default reporting interface can feel cluttered. Here are the reports that deliver the most value for paid media evaluation:

Acquisition › Traffic acquisition

This shows you where your sessions are coming from, broken down by channel — Paid Search, Paid Social, Organic Search, Direct, and so on. Use this to get a channel-level view of which sources are driving traffic, and cross-reference with conversions to understand which channels are producing results versus just volume.

Advertising › Conversion paths

This is one of GA4's most useful additions for paid media. It shows the sequence of touchpoints people go through before converting — which helps you understand the role each channel plays in the customer journey. Paid search might be consistently present earlier in the journey even when it's not the final click. That's worth knowing before you make budget decisions based on last-click attribution alone.

Engagement › Landing pages

This shows which pages people land on from your ads, along with engagement metrics and conversion rates per page. If your paid traffic is landing on pages with very low engagement or conversion rates, that's a strong signal that either the wrong page is being used as a landing page, or the page itself needs work.

Explorations › Funnel exploration

This is a custom report type that lets you map out a conversion funnel — for example, landing page visit → product page view → add to cart → purchase — and see where users are dropping off at each stage. It's particularly valuable for e-commerce accounts where you want to understand whether you have a traffic problem or a conversion problem.

Common GA4 mistakes that affect paid media performance

A few of the issues we see most frequently when auditing GA4 setups:

• Conversion events firing on page load rather than on action completion — for example, the purchase event firing when someone reaches the checkout page rather than the confirmation page
• All GA4 conversions imported into Google Ads without being reviewed — including low-value events that dilute Smart Bidding signals
• Auto-tagging disabled in Google Ads, causing paid traffic to be misattributed as organic in GA4
• Internal traffic not filtered out — staff browsing the website being counted as user sessions and inflating engagement metrics
• No currency or transaction value being passed through with purchase events — meaning GA4 records conversions but has no way of calculating revenue or ROAS
• Duplicate GA4 tags — the property being tagged both directly in the website code and via GTM, causing every event to be counted twice

GA4 doesn't need to be complicated — it needs to be correct

The goal with GA4 for paid media isn't to track everything. It's to track the right things accurately, import the right events into your ad platforms, and use the reporting to make better decisions about where your budget goes.

A GA4 setup that does that well — even a relatively simple one — is worth far more than an elaborate one full of events that don't connect to business outcomes.

If you're not confident your GA4 is set up correctly, or you want to know whether the data feeding your ad campaigns is reliable, a free PPC audit is usually the right starting point. Get in touch and we can take a look.