Seasonality Adjustment

What is a Seasonality Adjustment?

Without a Seasonality Adjustment, Smart Bidding reacts too slowly to seasonal peaks like Black Friday or Christmas — the algorithm takes days to recognize changed conversion rates. With a proactive adjustment, you inform the AI in advance and avoid your bids being too low during the most important sales period. Use Seasonality Adjustments only for short, clearly defined events — for long-term trends, Smart Bidding uses its own learning capability.

Seasonality Adjustments are a control feature in Google Ads that let you inform Smart Bidding in advance about expected changes in conversion rate. When you know that a specific event like Black Friday, a flash sale, or an industry trade show will significantly change the conversion rate in the short term, you tell the algorithm the expected percentage change.

Without a Seasonality Adjustment, Smart Bidding would have to learn the change from incoming data, which would be too slow for short-term events. The algorithm would bid too conservatively during a sale and only increase bids after the event when it’s already too late. With a Seasonality Adjustment, Smart Bidding adjusts bids immediately at the defined time.

Important for application: Seasonality Adjustments are intended only for short-term, predictable events, typically one to seven days. For long-term seasonal trends like the Christmas shopping season spanning several weeks, Smart Bidding learns on its own. Set the adjustment conservatively and monitor actual performance during the event. After the defined end time, the algorithm automatically returns to normal optimization without triggering a new Bid Strategy Learning Period.