Google has confirmed that most Google Posts are removed seven days after they are first published. The exception to this rule is Google Posts that are based on upcoming events. Event-based Google Posts are removed after the event date.
A Google spokesperson told us, “Posts enable merchants to share timely, relevant updates on Google Search and Maps. To ensure that posts are timely, they’re removed from the default view after seven days (or when the event date the post referenced has passed). However, a historical view of posts is shown under the Posts tab on mobile.”
Google Posts recently went live to most Google My Business customers. It enables these businesses to share timely messages to their customers, which show up in the local panel on web search and Google Maps.
Brodie Clark from optimising.com.au shared a screen shot of a notification Google sends to notify businesses that the Google Post will expire:
This information about when Google Posts expire is currently not in the Google Posts help documents.