A website should be audited for SEO at minimum once a year, but the right frequency depends on how actively the site is managed, how competitive the industry is, and whether Google has run major algorithm updates since the last audit. Most businesses that are actively investing in SEO benefit from a comprehensive audit every six months and a lighter monthly technical check as part of an ongoing program.

The purpose of an SEO audit is to find what has degraded, what has changed in the competitive landscape, and what technical issues have accumulated that are limiting performance. Sites are not static — content ages, technical problems accumulate, competitors improve, and algorithms update. An audit is the diagnostic that identifies all of that before it compounds into a significant traffic or ranking loss.

What does an SEO audit actually cover?

A comprehensive SEO audit has three layers: technical, on-page, and off-page. Technical covers site speed, crawlability, indexation, mobile usability, HTTPS, and Core Web Vitals. On-page covers content quality, keyword alignment, heading structure, meta data, internal linking, and whether pages are targeting the right queries at the right depth. Off-page covers the backlink profile — the quality, diversity, and growth rate of sites linking to yours, and whether any toxic links have accumulated.

How audit frequency should scale with site activity

A website that publishes new content weekly, adds new service pages regularly, or undergoes frequent development changes accumulates SEO issues faster. New pages can be accidentally noindexed; internal links break; content starts cannibalising other pages for the same keyword. An actively managed site benefits from a lightweight monthly technical check and a comprehensive audit every three to six months.

A smaller site that changes infrequently — a four-page service business website — needs less frequent auditing. Once a year is reasonable, with additional checks immediately following any algorithm update that caused a noticeable traffic change.

Google runs hundreds of algorithm updates per year. Not all of them matter, but the major ones — like the March 2024 core update — can change your rankings significantly. The only way to know whether you've been affected and what to do about it is an audit.

When to audit outside of the regular schedule

Certain events should trigger an unscheduled audit regardless of when the last one happened. A sudden drop in organic traffic visible in Google Search Console or your analytics is the clearest signal. A site migration, redesign, or CMS change should always be followed by a technical audit — these processes frequently break SEO elements that were working. A major Google algorithm update that coincides with a traffic change is another trigger: the audit identifies what the update reacted to.

What should be done with audit findings?

An audit produces findings at different priority levels. Critical issues — pages incorrectly blocked from crawling, canonical errors, broken redirects — should be resolved within days. High-priority issues — thin content, missing meta descriptions, slow page speed — should be scheduled for the next development sprint. Lower-priority opportunities — internal linking improvements, content expansion targets — feed into an ongoing content and SEO roadmap. An audit without a prioritised action plan is a report, not a program. See how to evaluate whether your SEO agency is actually working for what accountability should look like around audit findings.

Keep reading: why do competitors rank higher than me? often has answers that emerge directly from an audit comparison.