What Is Changing on August 17?
Starting August 17, Google Ads will automatically adjust how target-based bidding (Target CPA and Target ROAS) works for campaigns that are limited by budget. Currently, if your campaign is budget-constrained, it often over-delivers—spending less than your target allows. After the change, the algorithm will push actual performance closer to the target you set. If your $100 CPA target was delivering at $50, expect it to drift toward $100. This applies to Search, Shopping, Performance Max, Demand Gen, Travel, and Display campaigns. App, Video reach, and Video view campaigns are excluded.
Why This Matters for Your Business
If you run ecommerce campaigns on Target CPA or Target ROAS and any are flagged “Limited by budget,” your hidden efficiency is about to vanish. Many small and midsize stores have targets set as rough ceilings that were never revisited because the campaign beat them every month. After August 17, those targets become live. A 400% ROAS target that was actually running at 600% will drift down, eroding profit. The change is automatic—Google will not adjust your targets or budgets. You must act before the rollout.
Your Three Options Per Campaign
For each budget-limited campaign beating its target, you have three choices: 1) Reset the target to match actual performance using the Bid Target Adjustment Tool (live since July 6). 2) Raise the budget so the campaign is no longer budget-limited, allowing it to scale at your true target. 3) Accept the drift toward target if your stated target reflects genuine break-even. The key is to choose deliberately, not inherit a surprise.
Strategic Implications for Ecommerce PPC
For Shopping and Performance Max campaigns on Target ROAS, the drift means lower ROAS and more spend on marginal conversions. Thin-margin catalogs could see profit erode. Reset your target to a real contribution-margin-based floor. Also, Performance Max may shift traffic between channels as the system rebalances—watch channel-level reports post-August 17. If you want incremental volume, Smart Bidding Exploration (expanded June 15) lets you set a ROAS tolerance to explore new queries. Google’s testing showed an 18% lift in unique converting query categories and a 19% lift in conversions. Promotion Mode (beta) is another tool for flash sales.
What This Means for Your Business
If you run ecommerce campaigns with target-based bidding and any are limited by budget, this directly affects your cost per conversion and ROAS. The change rewards running targets that reflect real business math. Audit every budget-limited campaign, decide per campaign whether to reset, scale, or accept drift, and use the Bid Target Adjustment Tool to lock in efficiency. Brief your team or clients before August 17 to avoid surprise cost increases. If you ignore this, you’ll see a cost increase in next month’s reporting that you’ll have to explain after the fact.
Your Move:
Audit every campaign flagged “Limited by budget” with Target CPA or Target ROAS, compare actual vs. target over 90 days, and use the Bid Target Adjustment Tool to reset targets to actual performance before August 17.
FAQ
Target CPA and Target ROAS campaigns across Search, Shopping, Performance Max, Demand Gen, Travel, and Display that are limited by budget. App, Video reach, and Video view campaigns are excluded.
Use the Bid Target Adjustment Tool (live since July 6) to reset your target to match actual performance. Alternatively, raise your budget so the campaign is no longer budget-limited, or accept the drift if your target reflects true break-even.
