Anchor (footer) sticky vs sticky sidebar rail

Anchor (footer) sticky vs sticky sidebar rail

What it does — both keep a unit in view longer. The anchor pins a 320x50/728x90 to the bottom edge; the sticky rail pins a 300x600 in the sidebar gutter as you scroll.

Setup effort (1-5) — Anchor: 2 (often a Google toggle). Rail: 3 (position sticky + collision math with footer/comments).

RPM lift seen — Anchor: +8-15% on mobile where the rail can't exist. Sticky rail: +12-22% on desktop, the 300x600 holds premium eCPM and viewability near 90%.

Pros / Cons —
Anchor: huge mobile viewability, but eats UX and competes with your own CTAs.
Rail: high-value format, great viewability, but needs gutter width and breaks on short articles.

Verdict — They're not rivals, they're per-device. Run the anchor on mobile, the sticky 300x600 on desktop. Don't stack both on one viewport.

Lift: ★★★★☆ — Risk: ★★☆☆☆
Best for: article sites with a real sidebar. Skip the rail on edge-to-edge mobile-first templates.