What Google says
In Google's own words: “Target ROAS sets bids to help get as much conversion value as possible at the target return on ad spend (ROAS) you set.” (Google help center)
How Target ROAS works
You give Google a return on ad spend target, and its Smart Bidding only bids into auctions where it predicts it can hit that return, adjusting each bid to maximize total conversion value. It is optimizing toward a value goal, not capping any single cost. It is the value-based sibling of Target CPA, which optimizes toward a cost per conversion instead.
It is hungry for conversion volume
Value-based bidding can only predict a return if it has enough conversions to learn from. Google's minimum for Target ROAS on Search and Shopping is 15 conversions in the past 30 days, and it is far steadier with several times that. On a niche, low-volume campaign there is not enough signal, so a normal quiet week reads as failure and Google throttles delivery to protect the target, which starves it further. We unpack that death spiral, and the fix, in why your Target ROAS campaign keeps stalling out.
Changing the target restarts learning
tROAS is Smart Bidding, so editing the target is a bid strategy change that re-enters the learning period. Repeatedly lowering the target to revive a stalled campaign just keeps it in permanent relearning. If you cannot feed a value target honestly yet, Maximize conversions asks for no target at all and is the safer home for low volume.
The August 2026 change for budget-limited campaigns
Since August 17, 2026, Google bids target-based campaigns that are limited by budget more consistently toward the stated target, even when budgets change. A budget-limited campaign that had been beating its Target ROAS now trends down toward it, and Google will not move the target for you. If the recent return is the one you want, raise the target to match it, then scale with budget.
A worked example
Say a Search campaign spent $2,000 last month and recorded $9,000 in conversion value, a 450% ROAS ($9,000 / $2,000 x 100). Set a Target ROAS of 500% and you are asking for $10,000 of value from the same $2,000, so the bidder skips the auctions it predicts will return less and conversion volume usually drops. Set it at 400% instead and it can enter more auctions, trading some return for volume. Illustrative numbers, not a client result.
Common questions
What is Target ROAS in Google Ads?
Target ROAS (tROAS) is a value-based Smart Bidding strategy where you set the return on ad spend you want and Google bids automatically to maximize conversion value at that target. Google now labels it simply 'Target ROAS'.
How many conversions does Target ROAS need?
Google's minimum on Search and Shopping is 15 conversions in the past 30 days (Demand Gen needs 50 in 35 days). Value bidding is far steadier well above that floor; below it, the algorithm has too little to learn from and delivery becomes unstable.
Why did my Target ROAS campaign stop spending?
On low volume, a quiet week reads as the campaign missing its return, so Google lowers bids and delivery to protect the target. Less delivery means fewer conversions, which deepens the pullback. It is starving for signal, not failing.
How do you calculate Target ROAS?
Divide the conversion value you want by the ad spend and multiply by 100: $5 of sales for every $1 spent is a 500% Target ROAS. Google suggests basing it on your historical Conv. value/cost column multiplied by 100, excluding the most recent conversion-delay period.
What changed for Target ROAS on August 17, 2026?
For campaigns that are limited by budget, Google now bids more consistently toward the stated target, so a campaign that was beating its Target ROAS will trend down toward it. Google will not adjust targets for you, so if you want to keep recent performance, raise the target to match it using the Bid Target Adjustment Tool.
Should I raise or lower my Target ROAS?
Lower it gradually to get more conversion volume, because the bid strategy can enter more auctions; raise it to prioritize return, knowing that a target set too high may limit traffic. Give each change 1 to 2 conversion cycles before judging it.