Your conversions are up 40 percent month over month. ROAS looks fantastic. Nothing changed in the actual business: no new product, no pricing move, no traffic spike. Before you take a victory lap, ask one question. Are you counting some of those sales twice?
In a lot of Google Ads accounts, the answer is yes. And the culprit is not fraud or a glitch. It is two conversion actions quietly tracking the same sale.
How Two Actions Track One Sale
A conversion can reach Google Ads through two separate pipes. There is the GA4 import, where a GA4 purchase event gets pulled into Google Ads as a conversion action. And there is the direct path: the Google Ads tag, Enhanced Conversions, or an offline upload sending the same purchase straight in.
If both are switched on, both fire for the same buyer. One sale, two conversion actions, two entries in your Conversions column. We mapped those two pipes in Why Your GA4 and Google Ads Conversion Numbers Never Match.
Google Ads Only Dedupes Within an Action, Not Across Them
Google Ads does have deduplication. If the same order ID hits the same conversion action twice, it will collapse the two into one. The catch: that dedup only works inside a single conversion action.
Two separate conversion actions are two separate ledgers. Google Ads does not cross-check an order ID on your GA4-imported action against the same order ID on your Enhanced Conversions action. As far as the system is concerned, those are two different conversions that happen to share a number. Both count.
So the exact mechanism you would assume protects you, order-level dedup, does nothing across two actions tracking the same event.
This Is Worse Than a Vanity-Metric Problem
If double-counting only inflated a slide in your monthly report, it would be annoying and survivable. It does more than that. The inflated count feeds Smart Bidding.
Smart Bidding sets bids based on how valuable it believes each click is. Tell it every sale is worth roughly twice what it actually is, and it will bid up accordingly, chasing conversions that are partly accounting artifacts. You overspend, your reported ROAS stays rosy, and the gap between the dashboard and your bank account widens. The algorithm is working perfectly. The input is corrupt. (For more on how bad data quietly breaks the bidder, see Why Google and Meta Both Take Credit for the Same Sale.)
How to Find It in Five Minutes
Open Google Ads, go to Goals or Conversions, and look at your conversion actions list. Two things matter: the source of each action, and whether it is set to count toward Conversions.
Look for two actions tracking the same event from different sources. A purchase action sourced from Google Analytics (GA4) sitting next to a purchase action sourced from your website tag or an import. If both are marked Primary and both count purchases, you have found your double-count.
The Fix: One Primary, One Secondary
You do not delete one. You demote one. Google Ads lets you mark a conversion action as Primary (counts toward Conversions and drives bidding) or Secondary (visible for reference, not counted, not bid on).
Pick one action to be Primary and set the other to Secondary. Now Google Ads counts the sale once and bids on one clean number, while the second action stays available as a reference you can look at but never double-pay for.
Which action should win Primary? That comes down to what each one actually carries, and they are not equal. One can match a buyer even when the click trail breaks; the other cannot. We break that down in gclid vs. Enhanced Conversions: What Actually Travels With Your Sale.
Double-counting is one of the few tracking problems with a genuinely quick fix. Five minutes in the conversion settings can stop you from bidding against a number that was never real. Go look. There is a decent chance one of your best-looking metrics is partly a mirage.