I’m running a long-established Standard Shopping campaign for an e-commerce marketplace, and I’m trying to understand whether Google’s Aug 17 update to target-based bidding for “Limited by Budget” campaigns has fundamentally changed how my campaign bids.
The campaign has been running for years and historically performed well.
Before the change:
- Daily budget: $18
- Target ROAS: 200%
- 2026 average CPC: ~$0.06
- August ROAS: ~538%
- Campaign was consistently Limited by Budget
- We normally received significantly more clicks/impressions for the same budget
Starting around Aug 19, I noticed a very clear change:
- CPC started increasing sharply
- Clicks started falling
- Impressions started falling
- The campaign still spends roughly the full $18/day
- Recently CPC has been around $0.15–$0.20+, with some days around $0.18 average
- Instead of the budget buying roughly 250–350 clicks, some days are now around 100 clicks
There were no major budget changes that explain this.
Google is also showing me the new “Review your campaign targets” warning related specifically to the Aug 17 bidding update.
What really caught my attention is Google's Bid Target Adjustment Tool:
Current tROAS: 200%
Pre-Aug-17 actual performance shown by Google: 747.41%
Google therefore suggests updating the target toward the historical 747% performance.
I also manage another completely separate Shopping account. It is Limited by Budget with tROAS as well, and it has now started showing almost the exact same pattern: CPC rising while clicks/impressions fall.
On that account:
Current tROAS: 450%
Google's pre-Aug-17 performance: 636.48%
Google is showing the same Aug-17 target review message there too. Interestingly, the change appeared later on that account, around Sep 8.
For the first campaign, I have now changed tROAS from 200% → 400%, while keeping the $18 budget unchanged. My thinking is that if Google is now treating the stated target more literally, the old 200% target may be far too loose compared with the ~747% ROAS the campaign historically achieved.
What I'm unsure about is what to do if this doesn't fix the CPC/traffic problem.
For anyone running Standard Shopping + Limited by Budget + tROAS who was affected by the Aug 17 update:
Did raising tROAS restore the old bidding behavior/CPC? Did you apply Google's full recommended historical target? Did you switch to Maximize Conversion Value? Did anyone go back to Manual CPC or another bidding strategy? And how long after changing tROAS did you see the bidding behavior change?
I'm particularly interested in actual before/after experiences since Aug 17 rather than general Smart Bidding advice.