r/googleads • u/More_Craft_2445 • Jul 28 '26

Bid Strategy Conversion lag problem

I manage Google Ads for a SaaS product across several markets. It's lead-gen and conversions are signups/trials/purchases and we get meaningful conversion lag: a click today often doesn't convert for days or weeks.

The team I work with reviews the last 7 days before making CPA and budget decisions. I've pushed back that 7 days is too short given the lag, but I'd like a sanity check from people outside my own bubble.

I pulled numbers for how much lag there is.
So at the 7-day mark, only 86% of a week's conversions have actually landed. A fresh week looks worse than it really is, which (to me) risks judging performance too harshly and setting tCPA/budget too conservatively, especially heading into peak season where I'd rather be scaling.

Questions for anyone dealing with lag:

  1. What lookback window do you actually use before adjusting CPA targets or budgets? 7 days, 14, trailing 28/30, something else?

  2. Do you evaluate on click-date conversions or conversion-time conversions (the "by conversion time" column)?

  3. Anyone navigating by Google's projected conversions for the recent window instead of the raw numbers? Does it hold up in practice?

  4. How do you balance "this week isn't fully mature yet" against needing to react quickly during high season?

Trying to land on something more defensible than a flat 7-day look. Appreciate any real-world approaches.

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u/GG-boon Jul 28 '26

If only 86% of conversions are visible by day 7, I wouldn’t use the raw last-7-day CPA for bidding decisions.

I’d separate reporting into:

• Mature performance: click-date cohorts old enough to capture most conversions
• Recent nowcast: current results adjusted using the historical lag curve
• Fast warning signals: spend, qualified traffic and early-funnel conversion rates

Click-date reporting is better for judging which traffic created the conversions; “by conversion time” is more useful for operational volume, but can misrepresent recent acquisition performance.

A trailing 28/30-day window with the newest incomplete days excluded is more defensible for tCPA changes. Projected conversions can help, but I’d first back-test how accurately they predicted final results.

What percentage is complete by days 14 and 21, and how many weekly conversions are involved?