Why Google Ads and GA4 numbers don’t match (and which one is right)
Every results meeting has that moment: Google Ads shows 120 conversions, GA4 shows 84 and the CRM records 61 sales. Is someone wrong? Most of the time, no. Each tool answers a different question — and understanding that is what prevents bad budget decisions.
The most common causes
| Difference | Google Ads | GA4 |
|---|---|---|
| Conversion date | The date of the ad click | The date the event happened |
| Who gets credit | Only interactions with Google ads | Every channel the user touched |
| Attribution model | Set per conversion action | Set at property level, data-driven by default |
| Conversion window | Set per conversion action | Default of 30 days for acquisition and 90 days for other events |
| View-through conversions | May include conversions tied to video views | Doesn’t attribute them the same way |
| Modeling | Estimates some conversions that can’t be observed | Also models, with its own criteria |
The configuration errors that widen the gap
Auto-tagging turned off
Without the gclid parameter, GA4 may not recognize the visit as coming from Google Ads and may classify it under another channel.
Conversion counted twice
A Google Ads tag and a GA4 import active for the same event, both as primary actions, double the count in Google Ads.
Event firing more than once
A reloaded thank-you page or a form event set up in two places in GTM counts the same lead several times.
Consent and blockers
Visitors who decline cookies or use blockers go unobserved in different ways in each tool.
Different time zones
An ad account and GA4 property in different time zones shift conversions between days — and that shows up in daily reports.
So which number should you use?
Use it to: optimize bids, campaigns and ads within Google Ads. It’s the signal the platform’s algorithm uses.
Don’t use it to: compare Google Ads with other channels.
Use it to: compare channels against each other with the same yardstick and understand on-site behavior.
Don’t use it to: state how much money actually came in.
Use it to: measure real revenue, closed sales and true acquisition cost.
Don’t use it to: daily campaign optimization, because the data arrives late.
The right question isn’t “which number is right”, but “which number answers this decision”.
The mature solution is a dashboard showing all three side by side, with the expected gap documented. When the distance between them suddenly changes, something broke — and that’s when it’s worth investigating.
A diagnosis in five checks
Google Ads vs GA4 discrepancy checklist
Check each item before concluding there’s an error.
0 of 8 items
Configuration
Comparison
What gap is normal?
There’s no official acceptable percentage gap, because it depends on the type of business, the buying cycle and the weight of direct traffic and other channels. The practical route is to measure your own account’s historical gap for a few months and track how stable it is. A gap that stays stable over time is expected; a sudden jump usually points to a configuration change, a broken tag or a duplicated event.
How to reconcile Google Ads, GA4 and CRM in the same report
Define the source of truth for each question
Real revenue comes from the CRM or ERP; channel comparison from GA4; campaign optimization from Google Ads.
Record the source on the lead
Hidden fields with UTMs and source page carry the channel into the CRM.
Bring all three sources into Looker Studio
With date and channel filters aligned and a note explaining the expected gap.
Review monthly
Watch whether the gap between the sources shifts to a new level.
The custom Looker Studio report, with all sources integrated, is the final step of the onboarding for Paid Media and for Data & Analytics at Manáry.
Frequently asked questions
Why does Google Ads show more conversions than GA4?
Among the most common reasons are the conversion date being tied to the click in Google Ads, different attribution models and windows, conversions tied to video views and modeling differences.
Which number should I use in reports?
Use Google Ads to optimize campaigns, GA4 to compare channels and the CRM or ERP to measure real revenue. Ideally, show all three with the expected gap documented.
Does importing GA4 conversions into Google Ads fix the gap?
It reduces some differences in how the event is defined, but Google Ads still attributes by click date and by its own attribution logic.
Does consent mode affect the numbers?
Yes. When some visitors don’t consent to cookies, the tools observe fewer conversions and may use modeling to estimate some of them, each in its own way.
Do your numbers tell different stories?
We check the setup event by event and build a Looker Studio report with media, GA4 and CRM on the same screen.
Want to apply this to your business?
Manáry looks at your real numbers — media, website and CRM — and hands back the priorities in order of impact.
Get the next pieces by email
Calculators, checklists and practical guides. No spam, one-click unsubscribe.