In programmatic advertising, viewability is currency. An ad slot with 45% viewability is heavily discounted by DSP bidding algorithms. An ad slot with 85%+ certified viewability attracts intense buyer competition and commands top-tier CPMs.
No ad format delivers higher viewability than Sticky Anchor Ads—units that stay affixed to the viewport as the reader scrolls through editorial content.
However, poorly implemented sticky ads can frustrate readers, obscure navigation, and violate the Coalition for Better Ads guidelines.
Here is how to deploy sticky anchors that delight both users and programmatic advertisers.
Format 1: Mobile Bottom Sticky Anchor (320x50 & 320x100)
The mobile bottom anchor is the gold standard for mobile monetization:
+------------------------------------------+
| [ Mobile Editorial Article Content ] |
| |
| "Lorem ipsum dolor sit amet..." |
| |
+------------------------------------------+
| [X] ADVERTISEMENT (320x50 Anchor) |
+------------------------------------------+
#### Essential Implementation Rules:
1. Always Include a Visible Dismiss Button: Provide a clean [x] close button in the top-right corner with a touch target of at least 24x24px.
2. Never Cover Navigation or Action Buttons: Ensure the anchor does not overlap floating "Back to Top" controls or bottom cookie consent banners.
3. Height Restriction: Under Coalition for Better Ads standards, the anchor unit must never occupy more than 30% of the vertical screen height. A 320x50 or 320x100 banner is perfectly compliant.
Format 2: Desktop Sticky Side Rails (160x600 & 300x600)
On wide desktop screens (>1280px), wide margins often sit completely empty. Deploying sticky side rails in these margins generates high-impact impressions without altering the reading flow of your core text.
- Format: 160x600 wide skyscraper or 300x600 half-page.
- Behavior: The ad scrolls naturally until it hits the top offset (e.g.
top: 100px), locks into place alongside the content, and unpins cleanly before overlapping the site footer.
Revenue Impact: Sticky Anchors vs. In-Page Banners
In live publisher performance audits: - In-Content Inline 300x250: 52% average viewability, $1.45 eCPM. - Mobile Bottom 320x50 Anchor: 88% average viewability, $3.20 eCPM (+120%). - Desktop 160x600 Sticky Rail: 84% average viewability, $4.10 eCPM (+182%).
Every sticky anchor deployed by 54Bid's managed wrappers is engineered with responsive dismissing and zero Cumulative Layout Shift. Learn more about our technology or deploy sticky units on your publication.