SEO Silo
An SEO silo is a site architecture tactic that groups related pages into topic-based sections, using internal links to reinforce each section's theme for users and search engines.
- Also called
- Content silo, topic cluster, content pillar model
- Applies to
- Site architecture, internal linking, topical authority, content strategy
- Commonly confused with
- Keyword stuffing, directory structure alone, category pages without internal linking
Key points
- Silos concentrate internal linking around a clear subject area, helping crawlers understand topical relevance.
- A typical silo uses one pillar page with supporting pages that link back to it.
- Cross-silo links should be limited to avoid blurring topical boundaries between unrelated sections.
- Silos require periodic audits of internal links, content freshness, and orphan pages.
- Modern SEO prioritises helpful structure and natural linking over rigid isolation.
How it works
An SEO silo organises content into distinct topic groups, usually built around a broad pillar page with supporting pages covering subtopics underneath it. The pillar page links to each supporting page, and those supporting pages link back to the pillar, creating a confined internal link network that reinforces the central theme. Siloing seo can be implemented via URL/directory structure, internal linking, or both, depending on the site's CMS and architecture.
Silo planning typically begins with a content audit and keyword mapping, often carried out during an seo for website redesign to reassign existing pages to the correct topic theme. Navigation elements such as breadcrumbs and shallow click depth help users and crawlers move through the silo. Many practitioners also connect related supporting pages within the same silo when the links are contextually relevant, while cross-silo links are kept limited and intentional to preserve topical boundaries.
The structure is closely tied to seo foundations and topical authority, as concentrated internal linking signals to search engines that the site has depth on a specific subject. However, some SEO experts argue that rigid isolation is less important than natural internal linking, and the value of silos can change as content grows, so periodic re-audits are necessary rather than permanent rules.
Common mistakes
- Creating overly rigid silos that block useful contextual links between genuinely related pages, weakening the site's overall topical coverage.
- Using siloing without a keyword or topic map, which leads to pages being assigned to the wrong section and diluting the theme.
- Leaving orphan pages or broken internal links that prevent supporting content from being discovered and reinforced by the pillar page.
- Treating silos as a one-time setup instead of updating links, content, and structure over time, causing the architecture to become stale.
Questions people ask
What is SEO and how it works?
SEO stands for search engine optimisation, the practice of improving a website's visibility in organic search results. It works by aligning a site's content, technical structure, and authority signals with what search engines consider relevant and trustworthy for specific queries.
What is topical authority in SEO?
Topical authority is a measure of how comprehensively a website covers a particular subject. It is built by publishing in-depth, connected content on a topic and using internal links to show thematic depth, which is exactly what an SEO silo aims to achieve.
What is silo structure?
A silo structure is a site architecture that groups related pages into topic-based sections, with internal links reinforcing each section's theme. It typically uses a pillar page as the hub and supporting pages as spokes, limiting cross-links between unrelated topics to maintain topical clarity.
Sources
- Google Search Central Best source for Google’s guidance on crawlability, site structure, internal links, and how search systems discover content.
- Bruce Clay Well-known SEO reference with practical guidance on building silos, hierarchy, and internal linking.
- Ahrefs Useful for the modern SEO perspective that compares rigid silos with hub-and-spoke and natural internal linking.
- HubSpot Clear 2026-era explainer covering physical vs. virtual silos and implementation basics.
Written and maintained by Nora Lindholm. Last updated 27 July 2026.
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