Google Ads’ Target-Based Bidding Update For Ecommerce via @sejournal, @tonyadam

If you run ecommerce campaigns on target CPA or target ROAS and any of them sit at “Limited by budget,” Google’s August 17 bidding change is going to move your numbers, and we’re likely not talking about the direction you want. Starting August 17, campaigns that are limited by budget and use a target-based bid strategy will deliver more consistently toward the target you set instead of overshooting it. For the many accounts that have quietly been beating their targets, that means a higher cost per conversion or a lower ROAS unless you act first.

This one is not opt-in; Google is applying it automatically to eligible campaigns, and it has said it will not adjust your targets or budgets for you. The runway is getting shorter by the day. The Bid Target Adjustment Tool went live on July 6, and account notifications are landing now, with the change itself starting to roll out on August 17. That leaves a few weeks to decide, campaign by campaign, whether your over-delivery was a deliberate strategy or just a target you never updated.

What The Target-Based Bidding Update Changes

Today, a campaign that is limited by budget and running target CPA or target ROAS often beats its target, and it can swing around when you change the budget. After August 17, Google optimizes so that actual performance tracks closer to the target you set, including when you adjust budgets, which it frames as more predictable performance as you scale. Take a campaign with a $100 target CPA that has been delivering conversions at $50. After the change, it will move toward $100. The update applies to target-based campaigns across Search, Shopping, Performance Max, Demand Gen, Travel, and Display, while App, Video reach, and Video view campaigns are excluded. For multi-channel campaigns like Performance Max and Demand Gen, Google has also said you may see traffic shift between channels as the system rebalances toward the target.

Why Budget-Limited Campaigns Overdeliver

A campaign that is limited by budget beating its target was usually not a bidding miracle. The budget cap was the real constraint, so the algorithm never spent all the way up to the target. It bought the cheapest conversions it could inside the cap and left the rest of the target headroom untouched. That gap between your $50 actual and your $100 ceiling was efficiency you were getting for free, because budget, not the target, was doing the limiting.

After August 17, the system treats that headroom as room to work with. It will pursue additional conversions that cost more, which pulls your average up toward the target you set. In plain terms, your target stops being a ceiling you rarely touched and becomes a destination the algorithm actively aims for. This doesn’t mean that Google will actively raise your budget; it means the system pulls your actual performance up toward the stated target you already entered.

Google’s Ads Liaison Ginny Marvin has been clarifying the framing publicly, and two points are worth carrying into your own read. Bidding targets are meant to be your lever for efficiency and spend control, while Maximize Conversions and Maximize Conversion Value are the strategies built for a fixed budget with no target. She has also pushed back on the idea that this change is Google telling you to spend more, so treat August 17 as a reason to make your stated target honest rather than a nudge to loosen it.

The Real Risk Is A Bid Target You Never Tuned

Plenty of accounts carry a target CPA or target ROAS that someone set once as a rough ceiling and never revisited, because the campaign beat it every month anyway. Those targets are about to go live. If your $100 CPA was aspirational rather than a real break-even number, or your 400% ROAS target was a placeholder while the campaign quietly ran at 600%, August 17 exposes the gap. Miss it, and it surfaces in next month’s reporting as a cost increase you have to explain after the fact, which is a worse conversation than the one you could be having now.

The Decision For Each Budget Limited Campaign

For each campaign that is limited by budget and sitting comfortably inside its target, you have three honest options.

Reset the target to your actual performance. If a campaign has been running at a $50 CPA or a 600% ROAS and that is the efficiency you want to keep, update the target to match before August 17. The Bid Target Adjustment Tool lets you apply your recent performance as the new target in a couple of clicks, which holds your current numbers in place.

Raise the budget and scale at the stated target. If the overdelivery was really a sign the campaign could spend more, lift the budget so it is no longer limited by budget, and let it capture more volume at your true target. This is the growth path, and it only makes sense when the stated target reflects real profitability.

Let it drift toward the target on purpose. If your stated target was always your genuine break-even and you have been happy to take cheaper conversions while the budget cap allowed, you can accept the drift toward target and the added volume that comes with it. The point is to choose it, not to inherit it because you forgot to look.

How To Audit Your Bid Targets Before August 17

Pull every campaign flagged “Limited by budget” that uses Target CPA or Target ROAS. Compare actual CPA or ROAS to the stated target over the last 90 days, and flag any campaign where actual sits well inside target, because those are the ones that will move. Then apply the decision above to each.

The Bid Target Adjustment Tool, live in accounts since July 6, surfaces this historical performance and lets you apply updated targets directly, and the notifications Google is now sending point at where it thinks you are exposed, so treat them as a prompt to act rather than a recommendation to dismiss. One more step that has nothing to do with the platform: brief clients or your leadership before August 17, not after. A short proactive note about a possible cost shift beats explaining a surprise in next month’s report.

What The Update Means For Ecommerce PPC

Most accounts that regularly run “Limited by budget” are small and midsize stores, which is a large slice of ecommerce. On the Shopping and Performance Max side, two things are worth watching.

First, if you run Target ROAS on a budget-capped Shopping or Performance Max campaign that has been beating its target, the drift toward target shows up as a lower ROAS and more spend on the marginal conversion. For a thin margin catalog, that can quietly erase the profit you thought the campaign was printing. Reset the target to your real ROAS floor, ideally one built from contribution margin rather than a round number, before the change makes the call for you.

Second, because Performance Max spreads across Search, Shopping, YouTube, and more, Google has said you may also see traffic shift between channels as the system rebalances. Watch your channel-level reports in the weeks after August 17 so a move toward cheaper, lower-intent inventory does not slip past you.

Where Smart Bidding Exploration Fits

If your honest reaction is that you would take more volume, there is now a deliberate lever for that, instead of letting the August 17 drift spend your headroom at random. Smart Bidding Exploration, which Google expanded on June 15, lets you set a ROAS tolerance so the algorithm can bid on converting queries it would normally skip, widening reach beyond your current query coverage while staying inside a boundary you define. It is globally available for Performance Max campaigns without product feeds, and in beta for Shopping and Performance Max with feeds through your Google account team. Google reports that its own testing showed an 18% lift in unique converting query categories and a 19% lift in conversions, which are Google’s figures rather than independent ones, so treat them as directional.

The point for ecommerce is control. The August 17 change will use your headroom whether you want it to or not. Smart Bidding Exploration lets you decide how much of that headroom goes toward exploration and at what efficiency, which is a cleaner way to buy incremental volume than finding it in a report after the fact. Google also launched Promotion Mode in beta for Search and Performance Max, which schedules a temporary budget and ROAS tolerance boost for a defined peak window and then closes itself, so it is worth a look for flash sales and launches heading into Q4.

What To Do Before August 17

The August 17 bidding change rewards one discipline, which is running targets that reflect real business math instead of placeholders. Audit every campaign that is limited by budget and running Target CPA or Target ROAS, decide per campaign whether to reset the target, raise the budget, or accept the drift, and use the Bid Target Adjustment Tool, which is live now, to lock in the efficiency you want before the system settles it for you. If you would rather buy incremental volume on purpose than inherit it, Smart Bidding Exploration is the lever to reach for. The accounts that get caught out will be the ones that treated bid targets as set-and-forget ceilings, and this change turns every one of those ceilings into a live target.

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