An interstitial is a page or overlay that appears between the visitor and the content they came for. Google calls them intrusive when they cover the main content right after a visitor arrives or while they read, require dismissal before the page is usable, or push the content below a large banner that behaves like one. Google introduced an intrusive interstitial signal for mobile search in January 2017 and still lists avoiding them in its page experience guidance.
What Google treats as intrusive
Google's documentation gives examples of patterns that make content less accessible. The concern is content being hidden from someone who just clicked a search result, especially on small screens.
- A popup covering the main content immediately after arriving or while scrolling.
- A standalone interstitial the visitor must dismiss before reaching the content.
- A layout where the top of the page looks like an interstitial and the content sits below it.
What is generally fine
Google also describes interstitials used responsibly. These include notices required by law, such as cookie consent, age verification where content is age-restricted, login dialogs for content that is not publicly indexable, and banners that use a reasonable amount of screen space and are easy to dismiss.
How much it matters
Google describes page experience as one consideration among many and says it does not override relevance. In practice, intrusive interstitials are mainly a user experience problem that can also weaken how a page performs in search. Overlays can also push or shift content as they appear, which can affect Cumulative Layout Shift and the experience of reading on mobile.
Example
Replacing a full-screen popup
Hypothetical documentation platform Pebblestrand shows a full-screen newsletter modal two seconds after a visitor lands on any blog post. On mobile it covers the whole article. The team replaces it with an inline signup box after the third section and a small dismissible bar, then watches signups and organic engagement.
Common mistakes
Assuming consent banners are a problem
Legally required notices are in Google's acceptable list. Keep them compact, but you do not need to remove them for SEO.
Testing only on desktop
A modal that looks modest on a wide monitor can fill a phone screen. Check overlays on real mobile devices.
Questions
No. Google's guidance targets overlays that make content hard to access, particularly on arrival from search on mobile. Small, dismissible banners and legally required notices are treated differently.
