PPC briefing · 9 minute read
Google Is Changing Smart Bidding for Limited-by-Budget Campaigns
What the August 2026 Google Ads bidding change means for Target CPA and Target ROAS campaigns, with a safe account-review checklist.
Primary source
Google Ads Help
Source dated Effective from 17 August 2026. Our explanation and recommendations below are original editorial analysis.
What changed
The short version.
From 17 August 2026, Google says it will update how campaigns marked 'Limited by budget' optimise when they use target-based bidding. The change applies across several campaign types, including Search, Shopping, Performance Max, Demand Gen and Travel. Google says it will not automatically change daily budgets or bid targets.
Why it matters
What this changes for a business.
- 01
Campaigns performing better than their target while constrained by budget may change spending and delivery behaviour.
- 02
Account teams need a documented baseline before the rollout so normal variation is not mistaken for a crisis.
- 03
Budget and target decisions should remain tied to lead quality, margin and capacity rather than platform pressure alone.
Practical guide
How to prepare before 17 August
List affected campaigns
Filter for campaigns marked Limited by budget using Target CPA, Target ROAS or the applicable target-based strategy. Record campaign type, budget, target and recent conversion volume.
Validate conversion inputs
Check that primary conversion actions represent real business value. Smart bidding cannot optimise responsibly when weak actions, duplicate events or unqualified leads are counted as success.
Capture a pre-change baseline
Record spend, conversion value, CPA or ROAS, impression share, lost impression share and lead quality over a representative period. Note promotions or seasonality that distort comparison.
Review economics before raising budgets
Estimate the marginal value of additional conversions and whether the business can fulfil them. A campaign being limited by budget is not, by itself, a reason to spend more.
Avoid stacking unnecessary changes
Google advises against adding exclusions or bid limits solely because of the update. Keep the account stable enough to distinguish the platform change from your own edits.
Allow a stabilisation window
After rollout, monitor the account and wait through the recommended conversion-cycle period before making major strategic transitions, unless clear business risk requires intervention.
Avoid these mistakes
What not to do.
- Do not increase every limited campaign's budget automatically.
- Do not judge performance from one or two days of data.
- Do not optimise toward low-quality conversion actions simply because they produce volume.
Jet Fuel Digital view
This is a preparation and measurement update, not a reason for panic. Clean conversion data and sound unit economics matter more than chasing a platform status message.
Quick answers
Questions about this update.
Will Google automatically increase my budget?
Google states that it will not automatically change daily budgets or bid targets as part of this update.
Which strategies are affected?
Google names Target CPA, Target ROAS and Target CPC for Demand Gen, across the campaign types listed in its help guidance.