Interstitial Ads
Full-screen ads that appear between page views or content transitions, covering the entire viewport.
What are Interstitial Ads?
Interstitial ads are full-screen advertisements that cover the entire page or viewport, typically appearing during natural transition points — between page loads, during app-to-web transitions, or before accessing content. They require the user to either interact with the ad or close it before continuing to the content they were seeking.
Web interstitials are distinct from app interstitials. Google has strict policies about web interstitials to protect user experience, particularly on mobile. The company's "intrusive interstitial penalty" can negatively impact search rankings for sites that show interstitials that block content access, especially on mobile-first indexed pages.
Why It Matters for Publishers
Interstitial ads command some of the highest CPMs in display advertising — often $10-50+ for premium inventory — because they guarantee full-screen, 100% viewable impressions. However, they come with significant trade-offs. Poorly implemented interstitials increase bounce rates, frustrate users, and can trigger Google search ranking penalties.
Google's guidelines permit certain types of interstitials: those required by law (cookie consent, age verification), login dialogs for content behind paywalls, and interstitials that use a "reasonable amount of screen space" and are easily dismissible. Full-screen interstitials shown on page entry from organic search are the most likely to trigger penalties.
Tips for Optimization
- Show interstitials between pages, not on entry: Triggering an interstitial when a user navigates between articles is far less disruptive than blocking access to the first page they visit from search.
- Implement frequency capping: Limit interstitials to once per user session or every 3-5 page views to prevent user frustration and high bounce rates.
- Ensure easy dismissal: Provide a clear, visible close button. Avoid countdowns longer than 5 seconds, as they significantly increase bounce rates.
- Exclude mobile search entry: To avoid Google's intrusive interstitial penalty, do not show interstitials when users arrive from mobile search results.
- Test impact on engagement: A/B test pages with and without interstitials to measure the impact on bounce rate, pages per session, and return visits. Short-term revenue gains can mask long-term user loss.