SEO Silo
An SEO silo is a site architecture tactic that groups closely related pages into topic-based sections and links them in a way that reinforces each section’s theme for users and search engines.
Key takeaways
- Silos group pages by topic to strengthen topical authority.
- Use a pillar page with supporting pages that link back to it.
- Keep cross-silo links intentional and minimal.
- Plan with a keyword/topic map before building silos.
- Maintain silos over time—update links and content regularly.
Silos help search engines and users navigate your site by topic, improving crawl efficiency and topical authority.
Example
Imagine a gardening site with three main topics: Lawn Care, Vegetable Gardening, and Landscaping. Each topic becomes a silo.
- Lawn Care silo: Pillar page “Complete Guide to Lawn Care” links to supporting pages like “How to Mow,” “Fertilizing Schedule,” and “Weed Control.”
- Vegetable Gardening silo: Pillar page “Vegetable Gardening for Beginners” links to “Tomato Growing Tips,” “Soil Preparation,” and “Pest Management.”
- Internal linking: Supporting pages link back to their pillar page. Cross-silo links (e.g., from “Weed Control” to “Pest Management”) are used only when contextually relevant.
This structure tells Google that the site has deep expertise in each topic, not just scattered pages.
Quick Start
- Audit existing content – List all pages and identify their main topics.
- Map keywords to topics – Group related keywords into themes using a tool like Ahrefs or Google Trends.
- Choose a pillar page – For each theme, select or create a comprehensive page that covers the broad topic.
- Assign supporting pages – Move or link existing pages under the pillar page. Create new pages for uncovered subtopics.
- Build internal links – Link each supporting page to the pillar page and to other relevant supporting pages within the same silo.
- Limit cross-silo links – Keep links between different silos intentional and minimal to maintain topical focus.
How to Judge a Good Silo
- Clear topic grouping – Each silo covers one core theme, with no overlapping topics.
- Logical hierarchy – Pillar page at the top, supporting pages beneath it, with a clear parent-child relationship.
- Consistent internal linking – Every supporting page links back to the pillar page, and the pillar page links to all supporting pages.
- Shallow click depth – Users and crawlers can reach any page in the silo within 2–3 clicks from the homepage.
- Minimal cross-silo links – Links to other silos are rare and only when contextually necessary.
Common Mistakes
- Overly rigid silos – Blocking useful contextual links between genuinely related pages.
- Siloing without a keyword map – Pages get assigned to the wrong section, confusing both users and search engines.
- Orphan pages or broken links – Supporting content becomes undiscoverable, weakening the silo’s authority.
- Treating silos as a one-time setup – Links, content, and structure need regular updates to stay effective.
Next step
FAQ
What is an SEO silo?
An SEO silo is a way of organizing website content into distinct topic groups, with a pillar page and supporting pages that link to each other to reinforce the topic.
How do I create an SEO silo?
Start with a keyword/topic map, assign pages to themes, build a pillar page for each theme, link supporting pages to the pillar, and keep cross-silo links minimal.
What is the difference between a physical and virtual silo?
A physical silo uses URL/directory structure to separate topics; a virtual silo uses internal linking alone without changing URLs.
Related topics
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.
Reviewed by Lucía Marín, Founding editor.