If Google Ads reports more conversions than your order system recorded, the gap is almost never sophisticated. It is usually one of five mundane causes, and they compound.
1. The tag fires more than once
The most common cause by a distance. A conversion tag placed on a thank-you page fires again every time that page is reloaded, bookmarked or revisited. Some customers refresh out of habit. Others return to the confirmation page to check an order number.
It shows up clearly in the platform's own event log: the same transaction ID logged two or three times within a few minutes of each other. Deduplication settings catch some of it, but only if they were configured for this specific tag, not assumed to work by default.
2. Counting is set to “every” when it should be “one”
For lead generation this setting is nearly always wrong by default. A single prospect who submits three enquiry forms is one lead to your sales team and three conversions to your bid strategy.
3. The trigger is bound to a click, not a success
Binding a conversion to a submit button counts every attempt, including the ones that failed validation. The visitor who mistypes an email address three times generates three conversions and no lead.
4. Two containers are both firing
A migration that was never finished, or a developer-installed tag that nobody removed when tag management arrived. Both fire, both count, and the account has been running at double for months.
5. Refunds and cancellations never come back
Conversions are recorded at purchase and never adjusted. For any business with meaningful returns this inflates reported revenue permanently, and the bid strategy keeps buying whatever produced the returns.
Where to start
- Export conversions and orders for the same period and compare totals
- Check counting settings on every conversion action
- Look for more than one tag firing on the confirmation page
- Walk a real purchase, including a deliberately failed submission
- Confirm whether refunds are being fed back at all
None of this is difficult. It is just nobody's job, which is why it survives for years in accounts that are otherwise well run.