What is a content silo in SEO?
Definition
A content silo is a rigid site structure that walls pages into separate sections and limits links between them. It is an older alternative to topic clusters.
Silos come from an earlier era of SEO. The idea was to keep each section's authority "pure" by linking pages only within their own silo, often mirrored in the URL folders. It made sites tidy but brittle: real topics overlap, and a reader on one page often needs a page in another section.
Topic clusters keep the useful part of the idea, grouping related pages around a pillar, and drop the restriction. Pages link wherever it helps the reader, including across clusters when topics genuinely connect. The structure still signals what belongs together; it simply does not pretend that related subjects are unrelated. Folders can still reflect sections, but the links should follow meaning. For most sites, the cluster approach is the better default.
Why does it matter to your business?
If an old SEO plan walled your sections off from each other, your best pages may be missing the links that would help readers and search engines find them.
Related terms
Last reviewed September 11, 2026 by Joseph Nicholas Abear.
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