Most business owners understand that SEO involves content and keywords. Far fewer understand that there is a technical layer underneath that determines whether any of that content work actually reaches the search results. A site with poor technical foundations is like a brilliant book with half its pages missing — the quality of what is there does not matter if it cannot be accessed.

Technical SEO for traditional search rankings focuses on making your site fully accessible to Google’s crawlers, fast enough to meet page experience standards, and structured clearly enough for Google to understand what each page is about and how it relates to the rest of your site.

For AI search, technical fundamentals matter in exactly the same way. Google’s official AI guide confirmed that AI features draw from the same index as traditional search. A page with technical issues that prevent correct indexing is invisible to AI retrieval systems regardless of content quality. Getting this layer right is the prerequisite for everything else.

The technical SEO checklist for 2026

• 1
  HTTPS everywhere. Your entire site should load over HTTPS with a valid SSL certificate. Check for mixed content warnings (HTTP elements loading on an HTTPS page) using your browser’s developer tools or a tool like Why No Padlock. HTTP pages receive ranking disadvantages and browser warnings that dramatically increase bounce rates.
• 2
  Clean robots.txt file. Navigate to yourdomain.com/robots.txt and review what is blocked. A common issue is accidentally blocking Google from crawling important pages or sections. If you are not sure what should be in your robots.txt, err on the side of allowing everything and only add blocks for specific non-public pages like admin areas or duplicate parameter URLs.
• 3
  XML sitemap submitted to Search Console. Your sitemap should list every important page on your site and be submitted via Google Search Console (Settings → Sitemaps). Check that the sitemap contains no 404 or redirected URLs — a sitemap pointing to broken pages signals poor site maintenance to Google.
• 4
  Core Web Vitals passing. Check your key pages in Google PageSpeed Insights. Aim for: LCP under 2.5 seconds, CLS under 0.1, INP under 200ms. The most common fixes are optimising image sizes and formats (use WebP), reducing unused JavaScript, and implementing lazy loading for below-the-fold images.
• 5
  Mobile performance confirmed. Run your key pages through Google’s Mobile-Friendly Test. Text should be readable without zooming, tap targets (buttons and links) should be at least 48px in size, and content should not overflow its container horizontally. With most searches now conducted on mobile, mobile performance is not optional.
• 6
  Canonical tags implemented correctly. Every page should either have a self-referencing canonical tag or point to its preferred version. Common problems include: multiple URL variants of the same page without canonicals (with and without trailing slashes, with UTM parameters); paginated content without canonical handling; and duplicate content from faceted navigation on ecommerce sites.
• 7
  No broken internal links. Run your site through Ahrefs Webmaster Tools (free) or Screaming Frog to find internal links pointing to 404 pages. Each broken link wastes crawl budget, creates a poor user experience, and signals poor site maintenance. Fix by either updating the link destination or setting up a 301 redirect from the old URL.
• 8
  Structured data implemented and error-free. Check your structured data using Google’s Rich Results Test. LocalBusiness, Product, Article, and FAQ schema are the most commonly applicable for business sites. Errors in your schema markup — missing required fields, incorrect types — can prevent rich results from appearing and reduce AI system understanding of your content.
• 9
  No index bloat from low-value pages. Check that Google is not wasting crawl budget on tag archives, date archives, search result pages, or thin filtered pages that should not be in the index. Use noindex tags or robots.txt blocks on pages that provide no search value. Every low-value page indexed is a page taking attention away from your important content.
• 10
  Image optimisation confirmed. Every image should have a descriptive alt attribute (not “image001.jpg” but a description of what the image shows). Images should be compressed and in a modern format (WebP preferred). Large, uncompressed images are one of the most common causes of slow LCP scores and high mobile page load times.

If you need help auditing the technical health of your website or prioritising which fixes will have the most impact for your specific situation, get in touch here.