How to Optimise Technical SEO for eCommerce Websites

Most “technical SEO checklists” tell you to fix canonical tags, crawl budget, and Core Web Vitals without explaining exactly why those issues exist in the first place or what changes when you fix them. Our guide closes this gap. 

Instead of the traditional bullet-point audit lists, we will walk you through a single hypothetical case of:

Every technical SEO concept below is explained through what actually went wrong on their site, how it was diagnosed, and what fixing it did to their organic performance. If you’re new to technical SEO, you’ll get the concept in plain English. If you’re a specialist, you’ll get the diagnostic logic behind each fix, the part most guides skip. 

Why Technical SEO Decides Whether Everything Else Works

Why, you ask? Because Google was crawling less than 40% of their indexable pages in a given month, according to their Search Console crawl stats report. No amount of content or backlinks fixes a site that search engines can’t efficiently reach. 

This is the part beginners underestimate: technical SEO for ecommerce websites isn’t one input among many, but the plumbing that everything else runs through. A brilliant product description on a page Google never crawls generates zero organic value. 

The Crawl Budget Problem

This is the problem that mostly hides in plain sight. NestlyHome’s platform generated a filtered URL for every combination of colour, size, and price range on their category page, which is a standard behaviour on most e-commerce platforms, including Shopify and Magento. 

For a “Cushions” category having 12 colour options and 5 size options, there are potentially 60+ near-duplicate URLs, all indexable by default and all technically “different” pages to a crawler, even though the content on each was 90% identical. 

Now multiply that number by 200+ category pages, and you get around 38,000 crawlable URLs for a store with 4000 actual products. Googlebot was spending a limited crawl budget on filter combinations that nobody was searching for, rather than on products and categories that actually mattered. 

How to Fix Crawl Budget Issues on Ecommerce Site?

Answer: Signal Rather Than Delete

• Add “rel=canonical” tags pointing filtered URLs back to their parent category page. 
• Block faceted navigation parameters in robots.txt where canonicalisation alone was not sufficient. 
• Add noindex and follow to filter combinations that had genuine long-tail search value but were not worth indexing individually. 

Within six weeks, Search Console showed crawl requests to priority category and product pages up by 61%, without any change to backlinks or content volume. 

This is the mechanism most beginners miss: fixing crawl budget doesn’t create new rankings on its own; it removes the ceiling that was capping everything else. 

Site Architecture and Internal Linking

NestlyHome’s category pages were four levels deep for some products: 

Home > Living Room > Soft Furnishings > Cushions > Velvet Cushions. 

They had no internal links, connecting sibling categories or pointing back up the hierarchy inconsistently 

Several product pages were only reachable via search filters, meaning they had no stable internal link pointing to them at all. In SEO terms, these are orphan pages; technically live, but functionally invisible to both users and crawlers. 

How to optimise product pages for technical SEO? The only possible way is to restructure their internal linking around a flatter, topic-clustered model, which means:

“No product page should be more than 3 clicks away from the homepage, and every category page links both up to its parent and across to related categories.”

This is the same SILO-style internal linking logic that underpins a solid SEO strategy for small businesses as well as large catalogues. The principle doesn’t change with scale; only the execution complexity does. 

Result: Orphan pages dropped from around 900 to fewer than 40 within one crawl cycle, and average crawl depth to product pages fell from 5 clicks to 2.8. 

Page Speed and Core Web Vitals 

NestlyHome’s product pages were loading in 4.8 seconds on mobile, way past Google’s Core Web Vitals threshold. This issue works against you, and real shoppers start abandoning their carts. 

Their Largest Contentful Paint (LCP), a Core Web Vitals metric, gets dragged down by unoptimised and heavy product images (over 2MB, uncompressed and served at full resolution regardless of device). 

The technical fixes of core web vitals for ecommerce product pages that are effective:

• Converting product images to WebP with responsive sizing
• Lazy-loading below-the-fold gallery images instead of loading all variants upfront
• Deferring non-critical JavaScript (chat widgets, review plugin scripts) until after page interactivity
• Implementing a CDN (Content Delivery Network) for static assets

Making these technical fixes dropped LCP from 4.8s to 2.1s. This isn’t just a ranking factor tweak; Google has been explicit that Core Web Vitals sit inside the page experience signals it uses for ranking, but the more immediate impact was on conversion: NestlyHome’s mobile bounce rate fell noticeably in the same period. 

Technical SEO and commercial performance aren’t separate conversations; on eCommerce sites, they’re the same conversation. This is also where web development and design decisions and SEO stop being separate workstreams. Speed fixes usually require front-end and infrastructure changes, not just SEO configuration.

Schema Markup That Search Engines Can Actually Use

NestlyHome had Product schema implemented but was missing aggregate rating, availability, and priceValidUntil, and several other product variants were not marked up in the XML sitemap at all. 

Schema markup for ecommerce product pages is not just decorative code; it’s structured data that tells search engines (and increasingly AI-driven answer engines) exactly what the page is about, without needing to infer it from unstructured text. 

Implement:

• Full product schema with price, availability, and review data across all live SKUs.
• BreadcrumbList schema matching the actual site hierarchy

The visible result NestlyHome can see by implementing these changes is the rich snippets, star ratings and stock status appearing directly in search results, which measurably improve CTR without any changes in ranking positions. 

Schema doesn’t just help the traditional search but also the AI-driven search and answer engines, which summarise and cite structured content directly. A well-implemented schema markup is becoming a part of how you get surfaced in those results, too.

Handling Out-of-Stock and Discontinued Products

A detail that most technical SEO audits for ecommerce website skip is accounting for the discontinued products. 

NestlyHome had 300+ discontinued product pages, returning a 200 status code with “Out-of-Stock” text but no redirect and no alternative. Google was indexing the dead-end pages too, and users landing on them had no other useful pages to go to. 

Here, implement a decision tree instead of a blanket rule:

• Temporarily out of stock, restocking within 30 days → keep page live, keep indexed, no redirect
• Permanently discontinued with a clear replacement → 301 redirect to the closest matching live product
• Permanently discontinued with no replacement → 410 (Gone) status, removed from the sitemap permanently

Out-of-stock page SEO best practices reduced soft-404 errors flagged in Search Console by over 80% and stopped search engines from wasting crawl budget on dead ends, reinforcing the crawl budget work done in step one. Technical SEO for ecommerce websites fixes compound; they rarely work in isolation.

Mobile Usability and Rendering

NestlyHome’s site was technically “mobile-friendly” by Google’s basic test; however their filter and sort UI relied on JavaScript that did not render completely correctly during Googlebot’s initial crawl pass in some cases. It means that filtered results are occasionally indexed with missing content. 

This is a common blind spot: passing a mobile-friendly test and being properly crawlable are not the same thing. 

In order to spot this issue and surface the gap, test the rendered output through Google Search Console’s URL Inspection tool; it compares what the users see with what Googlebot renders. Fix it by rendering server-side for critical filter states rather than relying entirely on client-side JavaScript. 

Let’s Put It All Together: NestlyHome 

None of the six fixes was exciting individually. Combined, over roughly four months: 

1. Indexed pages matching actual product/category count (down from 38,000+ inflated URLs to a clean ~4,300)
2. Crawl requests to priority pages up 61%
3. Orphan pages down from ~900 to under 40
4. Mobile LCP improved from 4.8s to 2.1s
5. Soft-404 errors down over 80%

Organic ranking increased steadily across the same period, not because of one big dramatic change, but because of the technical foundation that stopped working against the content and links already in place. 

Technical SEO vs On-Page SEO: Where the Line Actually Sits 

A point where most business owners get confused, thus needs to be explained properly by a professional technical SEO consultant in the UK. 

Technical SEO

It covers how search engines crawl, render, and index your site. It deals with crawlability, site speed, schema, mobile rendering, and security (HTTPS).

On-page SEO 

It covers the content and elements on individual pages that communicate relevance to a specific search query. The relevant factors for on-page SEO are: title tags, headings, keyword usage, internal links within the copy, and image alt text. 

The simplest way to separate them is: technical SEO determines if a page can be found and understood at all; on-page seo determines whether it deserves to rank once it’s found.

NestlyHome’s product copy was reasonably well optimised on-page; the problem was entirely technical, which is why the content hadn’t moved the needle at all.  

Do You Need Technical SEO for Your Online Store?

If you see inconsistencies in your site’s indexability, if the pages published are not appearing in search months later, if your mobile load times are slow, or if you’ve never checked Search Console’s crawl stats or coverage reports, then YES. 

Technical SEO is not optional for your ecommerce website infrastructure; it is optional the same way a shop’s electrics are optional. You can operate without addressing it, but everything else, content, ads, conversion, is working harder than it needs to. 

Smaller businesses sometimes assume technical SEO for ecommerce websites is only relevant “at scale”. NestlyHome had 4000+ SKUs, but the same crawl budget and indexing issues show up proportionally on stores with a few hundred products too, just with lower stacks and smaller windows to fix before competitors overtake you. 

Conclusion

Technical SEO acts as the underlying plumbing for your eCommerce store and dictates whether your products surface for shoppers or get buried by structural bottlenecks. It isn’t merely a set of boxes to tick; it is the vital infrastructure ensuring that every other marketing effort, from content to backlinks, actually delivers results.

Should your organic growth hit a plateau, allow Infotech Business Solutions, the leading UK agency for your ecommerce technical SEO services, serving a global clientele, to refine your site’s technical core and remove the barriers holding your performance back today.

Frequently Asked Questions

What are the 4 types of SEO? 

The four commonly recognised types are technical SEO (crawlability, indexing, site speed, schema), on-page SEO (content, titles, headings, keyword relevance), off-page SEO (backlinks, authority, brand signals), and local SEO (Google Business Profile, local citations, location-based content). eCommerce sites typically need all four working together, with technical SEO acting as the foundation on which the others depend.

What is the difference between technical SEO and on-page SEO? 

Technical SEO determines whether search engines can crawl, render, and index a page correctly. On-page SEO determines whether that page is relevant and well-optimised for a specific search query once it’s found. A page can be perfectly optimised on-page and still fail to rank if it has technical issues preventing proper indexing.

Do I need technical SEO for my website? 

Suppose your site sells products or services online, yes. Technical SEO issues, slow load times, poor crawlability, duplicate URLs, and broken schema directly limit how much of your content and on-page work can actually be found and ranked. It’s not an optional add-on for larger sites; the same issues affect small stores too, just on a smaller scale.

What do I need to know about technical SEO before I start my eCommerce business in the UK? 

Plan your site architecture, URL structure, and platform choice with crawlability in mind from the start rather than retrofitting later. Understand how your chosen platform (Shopify, Magento, WooCommerce, or custom) handles faceted navigation and duplicate content by default. Ensure HTTPS and UK GDPR-compliant data handling are in place, and build schema markup in from launch rather than adding it once you have thousands of SKUs to retrofit.