The Technical SEO Checklist Every Business Site Should Pass

Technical SEO is unglamorous and disproportionately valuable. It will not write you better content, but it determines whether the content you have can be found, read and trusted. Most of the problems we find are not subtle — they are pages that cannot be crawled, or sites that load slowly on a phone.

1. Can Search Engines Reach Your Pages?

Start with the obvious failure modes, because they are more common than people expect:

• robots.txt — confirm it does not block anything important. A staging rule copied to production has taken entire sites out of the index.
• noindex tags — check both the meta tag and the X-Robots-Tag header. A header is easy to miss because it is invisible in the page source.
• Password or IP restrictions — anything gated is uncrawlable, which is exactly why staging sites should be gated.
• A valid XML sitemap — listing live, canonical URLs only, and referenced from robots.txt.

2. Is Your Content in the HTML?

If your site renders entirely in the browser, crawlers may see an empty shell. Fetch a page with JavaScript disabled, or view the raw source: if your headings and body text are not there, that is a serious problem.

Server-side rendering or static generation solves it. This is why we build with SSR by default in our front-end development work, and it is a recurring consideration when choosing between front-end frameworks.

3. One URL Per Page

Duplicate content usually comes from your own site: with and without www, HTTP and HTTPS, trailing slashes, URL parameters from filters and tracking. Each variation splits your signals.

Pick one canonical form, redirect the rest with 301s, and set rel="canonical" on every page. Filtered and sorted listing pages should generally canonicalise to the unfiltered version.

4. Core Web Vitals

Page experience is a ranking factor and, more importantly, a conversion factor. The three measures that matter are largest contentful paint, interaction responsiveness and layout stability.

The usual wins are unglamorous: compress and correctly size images, serve modern formats, set explicit width and height to stop layout shifting, defer non-critical JavaScript, and audit third-party scripts — marketing tags are frequently the single largest cost. We cover this in depth in speeding up a WordPress site, and it is the substance of website speed optimisation.

5. Mobile

Indexing is mobile-first, so the mobile version of your page is the version that counts. Check tap target sizes, readable text without zooming, and that content hidden on mobile is not content you need ranked.

6. Structured Data

Schema markup helps search engines understand what a page represents and can earn richer results. The useful types for most businesses are Organization, WebSite, BreadcrumbList, Product, FAQPage and Article. Mark up what is genuinely on the page — marking up content that is not visible risks a manual penalty.

7. Redirects and Broken Links

Every site accumulates dead links. Audit for 404s from internal links, chains where one redirect points to another, and — after any replatform — URLs that were dropped entirely. This is the most damaging item on the list during a migration, as we set out in our Magento to Shopify migration guide.

8. Internal Linking

Internal links tell search engines which pages matter and help visitors find related content. Link from articles to the relevant service pages with descriptive anchor text, and make sure every important page is reachable within a few clicks of the homepage. Orphan pages — reachable only from the sitemap — rarely rank.

9. HTTPS and Security

A valid certificate, no mixed content, and sensible security headers. Certificate expiry is an avoidable disaster that takes a site offline for everyone, so monitor renewals rather than trusting them.

Two related jobs sit just outside SEO but wreck it when they go wrong: a hacked site, which Google will flag and de-rank until it is cleaned (see hacked website cleanup), and a badly planned move between platforms, which we handle as website migration.

10. Keep Watching

Technical SEO is not a one-off project. Sites drift: plugins add scripts, editors publish duplicate pages, redirects pile up. Check Search Console monthly for coverage errors and monitor your Core Web Vitals over time. That ongoing attention is part of website maintenance and support, and where something is actively broken, troubleshooting and bug fixes.

If you would like this checklist run against your site properly, ask us for a technical SEO audit. We will tell you what is actually costing you visibility and what it would take to fix — see technical SEO optimisation for how we work.