Google is expanding the “Book Online” button through Reserve with Google partner integration to Search and Performance Max campaigns. Previously, this was only available on Google Local Service Ads and Maps ads.
Clicking the Book button will direct searchers from Google Ads to an advertiser’s scheduling platform to book appointments. This feature does not require additional setup from advertisers.

It’s worth noting that this update is not applicable to healthcare campaigns as Google Ads does not allow booking links or goals for these sectors.
This update was shared by Michel van Luijtelaar and Barry Schwartz.