Google Ads · Lead Generation
Every Smart Bidding failure in lead gen traces to the same arithmetic: the account cannot produce enough conversions, fast enough, for the algorithm to learn. Google publishes one set of minimums. The number its representatives give in the room is higher. This page lays out both, and the account structure that works when closed-won data cannot hit either.
Google publishes minimum conversion counts before Target ROAS works as intended. The figures below come from About Target ROAS bidding.
At least 15 conversions in the past 30 days, at the conversion tracking level.
At least 15 conversions with valid values in the past 30 days, across all of your campaigns combined.
At least 30 conversions in the past 30 days.
At least 50 conversions in the past 35 days in the campaign, 10 of them in the past 7 days, or 100 in 35 days across all Demand Gen campaigns in the account.
At least 10 conversions every day, or 300 in 30 days.
The same document adds two conditions that lead-gen accounts trip on. Values must be set before Target ROAS can be applied at all, and conversions must carry a value greater than 0 to be counted as eligible. An account that imports every lead at $0 is below every threshold on this page no matter how many forms get filled.
The document also sets a runway. For Search campaigns, Google recommends reporting conversion values for 4 weeks or 3 conversion cycles, whichever is longer, before adopting Target ROAS. A lead-gen account that flips value bidding on the day values start flowing is early by a month.
The published minimums mark where the feature turns on. They do not mark where it works. There is a second number, and it did not come from the documentation.
Unofficial guidance from Google representatives at an invite-only Google event, Toronto, November 2025: about 50 conversions per 30 days, landing within a 7-day conversion window of the click. Google has not published that figure and has not endorsed it in writing. It matches what we measure. Our own operating floor is 30 conversions a month, and targets hold without wild swings near 50.
Read the two conditions separately. Fifty a month is a volume problem. Within 7 days of the click is a speed problem. Lead gen usually fails the speed condition first: the conversions that matter commercially close weeks after the click, far outside the window the bidder learns from.
Volatility at thin volume is not noise you can average away. With 12 conversions a month, each one carries 8% of everything the bidder knows. One stray deal rewrites the account's idea of a normal conversion, and the target chases it for weeks.
What to feed the bidder once volume exists is its own discipline. We cover it in value-based bidding.
The reflex answer to thin data is more spend. For a long-cycle lead-gen business the math does not move: doubling budget on deals that close in 90 days still delivers zero closed-won conversions inside a 7-day window. The fix is structural, not financial. Four moves, in the order we make them:
Score the lead when it becomes qualified or turns into an opportunity, not when cash arrives. Qualification happens within days of the click, inside the window the bidder can see. Closed-won stays in your reporting; it stops being the bidding signal.
Any campaign type can bid deep into the funnel. Search campaigns pooled under a portfolio bid strategy combine their conversion learnings: five campaigns with 8 deep-funnel conversions each give Smart Bidding 40 to learn from.
If every conversion carries the same number, Target ROAS has nothing to rank. Identical values collapse it into Target CPA behavior with extra steps. Spread values by lead quality so the bidder can tell a strong lead from a cheap one.
Google's import pipeline reaches back 90 days at most, and only 14 for CRM connectors. A conversion uploaded after the window never enters the account. Details below.
That is the Google Ads strategy for low conversion volume lead gen accounts: value the qualified stage, pool the campaigns, vary the values, and land the data inside the window.
Order matters. Fix values before pooling. A portfolio built on campaigns that all feed identical or empty values combines nothing worth combining: you get the same flat signal, aggregated. Set qualified-stage values first, confirm they vary with lead quality, then pool.
Google's offline import documentation sets a hard boundary. File-based data sources import conversions from at most 90 days back. CRM connectors such as Salesforce and HubSpot run on a 14-day cycle. Google's own click-ID capture script expires the stored GCLID after 90 days. All three limits are documented in Set up offline conversions using Google Click ID.
A closed-won conversion uploaded on day 100 does not arrive late. It does not arrive. If your sales cycle regularly outruns the window, closed-won cannot be your bidding signal, and the qualified stage has to carry the value. The mechanics of getting that data in are covered in our guide to offline conversion tracking.
How much of this data survives the trip in practice is measurable. Our attribution benchmark tracks how reliably conversions trace back to clicks across real ad accounts.
Google's own numbers make the case for upgrading the import itself. Advertisers who added first-party identifiers alongside click IDs saw a median 10% increase in measured conversions compared to standard offline imports, per About offline conversion imports. At low volume, that recovered 10% can be the difference between 45 conversions a month and the 50 that stabilizes the bidder. Setup details are in our guide to enhanced conversions for leads.
Google's published minimum for Target ROAS on Search and Shopping campaigns is 15 conversions in the past 30 days. In practice we plan for 30 a month as a floor and see targets stabilize near 50. Between the published minimum and that floor, the strategy is available but volatile.
Bid to a conversion the account can produce at volume, then move value up the funnel as data allows. If several campaigns each fall short of the threshold, pool them under a portfolio bid strategy so their conversions combine into one learning signal.
Not on closed-won data alone. Deals that close in 60 or 90 days cannot land inside a 7-day conversion window at useful density. Assign value at the qualified or opportunity stage instead, so the bidder gets a signal while the deal is still young.
They help. Enhanced conversions for leads recover conversions that click-ID-only imports miss, which matters most when every conversion counts. They do not lower the thresholds, but they raise how much of your real volume Google actually records.
Only if they arrive fast enough and often enough. The working bar is about 50 conversions per month landing within a week of the click. Most lead-gen accounts cannot meet that with closed-won, which is why we bid to qualified-stage values with real dollar amounts attached.
Every platform claim on this page traces to Google's own documentation:
About Target ROAS bidding (conversion minimums by campaign type; value requirements)
Set up offline conversions using Google Click ID (GCLID) (import lookback windows; the 90-day click-ID expiry)
About offline conversion imports (the median 10% conversion increase from adding first-party identifiers)
Next Step
If you spend $30,000 or more per month on lead gen and Smart Bidding never seems to leave learning, the thresholds above are almost always the reason. We restructure the account and the value pipeline to clear them. Let's talk.
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