A topic cluster is a way of organizing content so that one broad page covers a subject at a high level and a set of supporting pages each go deep on a subtopic. The pages link to each other, which helps readers move through the subject and helps search engines see the site as covering the topic thoroughly. The model is also called hub and spoke, with the pillar as the hub.
How a cluster is built
- Pick a subject your buyers care about and your product relates to, such as “expense management”.
- Write a pillar page that covers the subject broadly and answers the main question.
- Write cluster pages for each subtopic that deserves its own depth: policies, approval workflows, receipt rules, per diems, reimbursement timelines.
- Link every cluster page to the pillar, the pillar to every cluster page, and cluster pages to each other where it helps the reader.
- Link from the cluster to relevant product and use-case pages.
Why it helps
Clusters keep a site organized. Each page has one clear job, which reduces the risk of several pages competing for the same search. The links between them make it easy for crawlers to discover new pages and for Google to understand how they relate.
Covering a subject thoroughly may also help a site build what SEOs call topical authority. Google does not publish a “topical authority” score, but it has said it looks for content that shows expertise, and a body of interlinked, in-depth pages is one way to show that.
Planning clusters for a SaaS site
Start from the problems the product solves, not from a keyword export. Each cluster should lead, through its links, toward a product page, use case or comparison. A cluster about a subject the product has nothing to do with may draw traffic but rarely draws customers.
Keyword research then fills in the subtopics: the questions, comparisons and how-to searches around the core subject.
Example
A cluster for an onboarding product
A made-up employee onboarding tool, Firstday, builds a cluster around “employee onboarding”. The pillar is a complete guide to onboarding. Cluster pages cover a first-week checklist, remote onboarding, onboarding for engineers, measuring time to productivity, and onboarding email templates.
Each cluster page links back to the guide and to the product feature it relates to, such as the checklist builder or automated welcome emails.
Common mistakes
Clusters with overlapping pages
Writing “onboarding checklist” and “new hire checklist” as separate pages usually splits one intent across two URLs. Merge them.
Linking only in a sidebar widget
Automated “related posts” boxes help, but contextual links within the text tell readers and search engines more about how pages relate.
Questions
As many as the subject genuinely needs. Some clusters are a pillar and four pages; others grow to dozens. Let the distinct search intents decide, not a target number.
Probably more, if anything. AI systems that answer a broad question often pull from several related subtopics, and a site with clear, well-linked pages on each one gives them more to draw on. How each system selects sources is not fully documented.
