Budget changes won't reset Smart Bidding learning

Google's Tal Akabas has said that changing a target or daily budget on a running campaign won't wipe out what Smart Bidding has learned. That's useful to know before Black Friday, but a few other settings from the same conversation can quietly move your money if you leave them on autopilot.

Smart Bidding is Google's automated bidding. It sets your bids for you, using a target such as tCPA (target cost per action, the price you'll pay per sale or lead).

What changed

Google Ads product liaison Ginny Marvin interviewed Akabas on her Ads Decoded podcast. Search Engine Journal's breakdown of the episode covers the details. I haven't been able to check Google's own documentation for each point, so treat the specifics below as the episode's account.

• Changing a tCPA, tROAS or budget on a steady-state campaign doesn't trigger "Learning" status or erase history. Performance can still shift.
• Google advises skipping seasonality adjustments for standard holiday spikes. Save them for surprises it can't anticipate.
• Promotion Mode is rolling out to Search and Performance Max. It lets you schedule a promotional window with its own budget and bid changes.
• Smart Bidding Exploration needs a tROAS campaign with a budget that doesn't limit spend. It's rolling out to Retail Performance Max and is coming to Shopping.
• Channel Prioritization and Budget Allocation are new controls for Search, Shopping, Performance Max and Demand Gen. They only matter on days your budget limits spend.
• Search campaigns using Display Expansion will move to new controls starting in February 2027. The podcast puts the switch in February to March.

What it means for you

Start with one question: do you run Search campaigns with Display Expansion turned on? If yes, the February switch will change where your money goes, and Google hasn't said the change will be neutral for your account. If no, most of this is background reading for now.

Anyone running Performance Max should look at the channel controls. Anyone planning a Black Friday seasonality toggle should read the seasonality section first.

The cost of doing nothing is mostly silent. Spend can shift between Search, Search Partners and Display without anyone choosing that shift. Nobody gets a warning email for that.

What to do

1. Leave targets and budgets alone unless the business changes. Google's advice is to allow for conversion delay and avoid repeated target changes inside one conversion cycle.
2. Don't switch on seasonality adjustments for ordinary Black Friday traffic. Keep them for something unusual, like an off-cycle flash sale or a discount much deeper than last year's.
3. If you run a scheduled sale, check whether Promotion Mode is available. The exact menu location isn't in the material I have, so confirm it in Google's help documentation rather than trusting a screenshot from a forum.
4. Audit Search campaigns that use Display Expansion now. To keep today's behavior, Search Engine Journal suggests setting Display to Low Priority with a 50% allocation. Do this before the February 2027 change, not during it.
5. Check your caps against real cost. Budget Allocation percentages apply to your daily budget setting, not your actual spend. Use the "Where your conversions come from" chart in the Performance Max Channel performance report, and toggle on Cost. For Search, Shopping and Demand Gen, segment by network.
6. Watch the "ghost budget" trap. The article's example: a $5,000 "uncapped" budget on a campaign that normally spends $500 a day. A 10% Display cap would still allow $500 a day on Display, which is the campaign's entire typical spend.