IT'S NUANCED
Interstitials always hurt mobile SEO
MOBILE
MEDIUM Impact
INTERMEDIATE
The Myth
"Any popup or interstitial on mobile damages your rankings."
The Truth
Only intrusive interstitials that block content are penalized. Legal requirements (cookie consent, age verification), app install banners that use reasonable screen space, and login dialogs for paywalled content are fine. The penalty targets interstitials that make content inaccessible, not all popups. Be reasonable about timing and size.
DInsight from @dejanseo
"Don't block your content with aggressive popups. Users hate it, Google penalizes it. If you need popups, make them easy to dismiss and don't cover the main content immediately."