What Ecommerce SEO Costs in the UK, What It Includes and How to Choose

Ecommerce SEO makes your online shop easier for search engines to crawl and understand, so the right shoppers land on your category and product pages and buy something. Done properly, it covers four jobs: technical fixes, page-level optimisation of categories and products, content mapped to how people shop, and authority building. Then it reports on orders and revenue, not just rankings. With internet sales making up 28.3% of all British retail in September 2026, according to the Office for National Statistics, a store that’s hard to find in search is leaving a large share of its market to competitors. This guide covers what ecommerce SEO includes, what drives the price in the UK, how it fits with the rest of your ecommerce marketing and how to judge any agency that pitches for the work. If you’d rather hand the whole job over, our SEO agency page explains how we run it.

TL;DR

• Ecommerce SEO has three layers: technical foundations, on-page work on category and product pages, and off-page authority. Google’s own documentation gives online shops specific rules on URLs, filters and product data.
• The best programmes give every important search term one page that’s clearly the best answer, from early research through to “buy now”.
• SEO pays most when it sits alongside paid media, email and conversion work, because traffic is only worth something when it turns into orders.
• Price depends on catalogue size, platform, site health and how competitive your categories are. Ask for a scoped proposal, not a flat rate.
• Judge any agency on what it reports: organic orders and revenue first, positions second.

Table of Contents

• What does ecommerce SEO actually involve?
• Technical foundations: crawling, filters and speed
• Category and product page optimisation
• Keyword research and the buying journey
• How SEO differs on Shopify, WooCommerce, Magento and custom builds
• How ecommerce SEO fits with the rest of your marketing
• Visibility in AI search
• What ecommerce SEO costs in the UK
• What results to expect, and when
• How to choose an ecommerce SEO agency
• Our perspective
• Where Castle fits
• FAQ
• Sources

What does ecommerce SEO actually involve?

It makes a large, constantly changing catalogue easy for Google to crawl, easy for shoppers to navigate, and worth ranking. That’s a different job from SEO for a ten-page brochure site. A shop has hundreds or thousands of near-identical URLs, filters that multiply pages, products that sell out and demand that swings with the seasons. A service built for ecommerce is designed around exactly those problems.

Shopify’s 2026 guide to ecommerce SEO splits the work into three areas, and it’s a sensible way to check what a proposal actually covers:

Technical SEO

• What it covers: site speed, mobile usability, URL structure, working links and crawlability.
• What you should receive: a crawl audit, a prioritised list of fixes and ongoing control of which URLs Google crawls and indexes.

On-page SEO

• What it covers: page titles, headings, product descriptions, image alt text and the keywords people actually use.
• What you should receive: optimised category and product templates, original copy for priority pages and an internal linking plan.

Off-page SEO

• What it covers: links from other websites, brand mentions, influencer activity and other external signals.
• What you should receive: digital PR, outreach and reporting on the mentions and links earned.

If a proposal only talks about one of these, you’re buying part of a service.

Technical foundations: crawling, filters and speed

Technical work comes first, because nothing else performs if Google struggles to get round the shop. Yoast’s ecommerce SEO guide names good hosting, SSL security and optimised URLs as the basics, and Google has a whole set of ecommerce best practices covering URL design, site structure, pagination and product data.

Filters and faceted navigation

This is where most shops quietly waste their crawl. Every combination of colour, size, price and brand can create its own URL. Google’s guidance on managing faceted navigation warns that this can produce a near-endless set of URLs, which leads to overcrawling and slows down the discovery of new pages you actually care about. Picture a stockroom where the staff spend all day counting the same boxes in different orders and never get round to unpacking the new delivery.

A good agency decides which filtered pages deserve to rank (say, “women’s waterproof walking boots” has real search demand) and which should be kept out of the crawl with robots.txt rules or other controls. It also checks that filter combinations with no products return a 404, which Google specifically recommends.

URLs, variants and duplicates

Google’s advice on URL structure for ecommerce sites is specific. Each product variant that you want found should have its own URL, because Google ignores the part after a # in a web address. Tracking codes and session IDs shouldn’t appear in internal links. Variant pages should point to the main product with a canonical tag. These sound like developer details, and they are, but getting them wrong splits your ranking signals across copies of the same page.

Site structure and internal links

Google’s guide to helping it understand an ecommerce site’s structure suggests linking to your best sellers from the home page, linking from menus to categories and from categories to sub-categories, and using standard links rather than JavaScript click events for navigation. It also “strongly” recommends linking to every product you want indexed. Simple stuff. Plenty of stores still miss it.

Speed, mobile and security

Template-level fixes help every product page at once, which is why they’re usually the best-value work in a technical phase. Shopify’s guide cites Dynamic Yield data showing more than 70% of ecommerce traffic now comes from mobile devices, so a slow mobile product page isn’t a minor inconvenience. It’s the main shop window.

If you want more on the audit stage, our guide to technical SEO services and what they include walks through the process, and our five ways to audit SEO on your ecommerce website shows where to look first.

Category and product page optimisation

Category pages usually carry the most commercial value, because they match broad searches like “women’s waterproof walking boots”. Product pages catch narrower, ready-to-buy searches. Both need work, and they need it at scale, through templates and consistent rules rather than one page at a time.

The biggest single mistake we see is copied supplier text. Shopify’s guide says plainly to avoid relying entirely on manufacturer descriptions or repeating the same copy across pages, and to write original descriptions that cover materials, sizing, fit, compatibility and use cases. If thirty other retailers carry the same paragraph, Google has no reason to pick yours.

A solid page-level service should deliver:

• Title tags and meta descriptions written around the words customers actually search with.
• Category copy that helps shoppers choose, with links to key sub-categories and best sellers.
• Product descriptions with original detail: sizing, materials, use cases and compatibility.
• Image optimisation, including descriptive file names and alt text.
• Product structured data. Google’s product markup documentation explains how it can show price, availability, review ratings and shipping details in results.
• Review and FAQ content where it genuinely helps a buying decision.
• Internal linking that passes authority from strong pages to the ones that need a lift.

There’s a second route for product data, too. Google recommends sharing product data both ways: structured data on your pages and a Merchant Center feed. Merchant Center is required to appear in the Shopping tab, so an ecommerce SEO service that ignores your feed is leaving a door shut.

Keyword research and the buying journey

Good research doesn’t end in one long spreadsheet of keywords. It ends with each term matched to a single page. That stops your own pages competing against each other, and it makes gaps obvious.

Using camping stoves as an example, a journey might look like this:

• Research: guides and comparisons that answer questions, such as “how to choose a camping stove”.
• Consideration: category pages and buying guides that narrow the choice, such as “lightweight backpacking stoves”.
• Purchase: product pages and brand-plus-product searches with clear commercial intent, such as “buy portable camping stove UK”.
• Retention: care, refill and accessory content that brings customers back, such as “camping stove gas canister compatibility”.

Each stage needs a different type of page, and most stores are strong at one (usually product pages) and thin everywhere else.

How SEO differs on Shopify, WooCommerce, Magento and custom builds

The principles are the same on every platform. The fixes aren’t. Some platforms create duplicate collection URLs, some load heavy apps and scripts that slow templates down, and some limit how much control you have over URL structure. A good agency knows where each platform tends to struggle and plans around it. If you’re weighing up a rebuild at the same time, our guide on how to choose a Shopify agency covers what to check.

Headless and bespoke builds need more coordination. Women in Tech SEO’s guide to SEO for headless commerce points out that a headless setup can push product updates to the website, mobile app and third-party marketplaces at the same time, and that coordinating those updates supports a more cohesive SEO strategy. It also advises putting internal links into server-rendered HTML. In plain terms, rendering, metadata and internal links have to be planned with the developers from day one. If your store runs on a custom front end, working with a team experienced in Next.js and React web development helps keep those SEO requirements in the code rather than bolted on afterwards.

On Shopify, we can handle both the optimisation and the build, as Shopify development and web design sit within our own team.

How ecommerce SEO fits with the rest of your marketing

Search rarely works alone. Organic rankings take time to build, paid media buys immediate visibility and testing data, and conversion work decides how much of the traffic actually buys. Each feeds the others:

• Paid search and paid social show which products, phrases and messages convert, which then sets SEO priorities.
• SEO lowers your long-term cost of winning customers by building traffic that doesn’t stop when the ad budget does.
• Conversion work raises the return from both, because a better product page helps every visitor, whichever channel brought them.

A worked example (illustrative)

Say a store gets 40,000 organic sessions a month, converts 1.5% of them and has an average order value of £60. That’s 600 orders and £36,000 of organic revenue a month. Now say the SEO work does nothing for traffic at all, but better category copy and product pages lift conversion to 1.8%. That’s 720 orders and £43,200 a month, an extra £7,200 without a single new visitor. These figures are made up to show the maths, not a prediction, but they show why rankings alone are the wrong scoreboard.

We look at the combined effect in more detail in the ROI of ecommerce SEO and paid ads working together, and at why visits alone aren’t the goal in ecommerce marketing in 2026: why traffic alone no longer converts.

It’s also why many shops end up looking for an ecommerce marketing agency rather than a pure SEO supplier. One team can decide where the next pound is best spent, instead of each channel defending its own budget.

Visibility in AI search

Shoppers now ask ChatGPT, Gemini and Google’s AI features for product recommendations as well as typing searches. Showing up there depends on clear, well-structured, trustworthy pages, which overlaps heavily with good ecommerce SEO: original product detail, accurate structured data, helpful buying guides and mentions on sites the AI tools already trust.

Generative engine optimisation (GEO) and answer engine optimisation (AEO) build on those same foundations. If you want to understand the difference, read our comparison of AI SEO and traditional SEO, our explainer on what GEO is, or our guide to earning LLM citations.

What ecommerce SEO costs in the UK

There’s no single UK rate, and flat prices quoted online deserve some suspicion. Ecommerce SEO is usually scoped above a basic local campaign because of the number of pages and the technical complexity. The main things that move the price:

• Catalogue size. Ten categories and 200 products is a very different job from 50 categories and 20,000 SKUs.
• Platform and build. Custom and headless stores need more developer involvement.
• Starting point. A store with crawl problems, duplicate content or a recent migration needs more groundwork.
• Competition. Crowded categories need more content and more authority building.
• Scope. Whether content writing, digital PR, paid media or development are included.

Most managed SEO is sold as a monthly retainer, with project fees for one-off work such as an audit, a migration or a rebuild. A quick way to sanity-check any quote: work out what extra revenue it needs to pay for itself. If a retainer were £1,500 a month (an illustrative figure) and your gross margin is 40%, organic search needs to bring in £3,750 of extra sales each month just to break even. If that number looks unreachable for your store, the scope is wrong, whoever is quoting.

At Castle we scope each project to the business and don’t publish fixed prices, so the way to get an accurate figure is a conversation about your store and your goals.

What results to expect, and when

SEO compounds. Technical fixes can show an effect within weeks, while new content and authority usually take months to settle. Shopify’s senior SEO lead Kyle Risley says SEO often takes three to six months to show meaningful progress, and competitive terms can take longer. Our own take on how long SEO takes to work goes into what speeds it up.

What nobody can do is guarantee a position. Google’s own advice on hiring an SEO is blunt: “No one can guarantee a #1 ranking on Google.” An agency that promises one is telling you something about itself.

A responsible agency agrees the measures that matter before work starts. Use Google Search Console for impressions, clicks and queries, and Google Analytics for sessions, behaviour and sales; our walkthrough on using Google Analytics to improve SEO shows which reports earn their keep. A healthy monthly report should answer five questions:

• How much organic traffic came in, and to which types of page?
• How many orders and how much revenue did organic search drive?
• Which categories and products gained or lost visibility?
• What was done this month, and what comes next?
• What’s limiting growth right now: technical issues, content gaps or authority?

How to choose an ecommerce SEO agency

Use criteria that separate real ecommerce experience from generic SEO. Google’s own list of questions to ask an SEO is a good starting point: ask for examples of previous work, how they measure success, their experience in your industry and whether they’ll share every change they make to your site. Then look at these six areas.

Ecommerce experience

Good looks like work on stores with a similar catalogue size, platform and sector. Ask to see a category page they improved and what happened to its revenue.

Reporting

Good looks like reports tied to enquiries, orders and revenue, not only keyword positions. Ask for a sample report before you sign.

Team

Good looks like technical, content and paid specialists who actually talk to each other. Ask who will work on your account week to week.

Process

Good looks like a clear audit, a prioritised roadmap and a regular review. Ask what the first 90 days include.

Scope

Good looks like a clear list of what’s included: content, links, development and paid media. Ask what costs extra.

Contract

Good looks like transparent terms and plain communication. Ask about notice periods and who owns the content and data if you leave.

Also think about whether you want one team for everything. Ours is in-house, which keeps SEO, paid media, development and analytics pulling in the same direction.

Our perspective

Most ecommerce SEO goes wrong at the measurement stage. A store can climb the rankings and still see flat sales if the traffic lands on weak pages, on out-of-stock products or on the wrong part of the range. We’ve seen beautifully ranked category pages that convert worse than the paid traffic going to the same place, and nobody noticed for months because the report only showed positions.

So we’d rather agree what a good month looks like in orders than in rankings. We combine traditional SEO with GEO and AEO, so a store can be found in Google and in AI-generated answers, and we tie our reporting to actual enquiries and revenue.

We also think search shouldn’t sit apart from the rest of your marketing. Paid ads, development, content and analytics all shape whether a visitor buys. When one in-house team handles them together, decisions get made faster and nothing falls between suppliers. Separate agencies arguing over who gets credit for a sale is a very expensive way to learn nothing.

Where Castle fits

Castle is a UK agency specialising in AI-driven SEO, GEO and AEO, with Google Ads, Meta Ads, Shopify development and analytics under the same roof. If you want your store found in both traditional search and AI platforms, with reporting you can trace to revenue, see our ecommerce marketing service or browse everything we offer.

Tell us about your store, your platform and what a good month looks like, and we’ll come back with a scoped proposal.

Talk to our SEO team

FAQ

What does ecommerce SEO include?

A full service usually covers a technical audit and fixes, keyword research mapped to pages, optimisation of category and product pages, product structured data, content, internal linking and authority building. It should also include monthly reporting on organic orders and revenue.

How is ecommerce SEO different from standard SEO?

Online shops have large numbers of similar pages, filters, variants and stock changes, which create crawl and duplication problems that smaller sites rarely face. Page-level optimisation also has to work at scale, through templates and consistent rules.

Do I need SEO and an ecommerce marketing agency?

Not necessarily as separate suppliers. SEO builds long-term visibility, while paid media, email and conversion work add immediate reach and improve the return on that traffic. One team handling both lets the channels share data and budget decisions.

How should I measure ecommerce SEO?

Use Google Search Console for impressions, clicks and queries, and Google Analytics for traffic, behaviour and sales. Treat rankings as a supporting indicator, with organic orders and revenue as the main measure.

How long does ecommerce SEO take to work?

Technical fixes can show an effect within weeks. Shopify’s senior SEO lead puts meaningful progress at three to six months for most sites, with competitive categories taking longer. Be wary of anyone who guarantees rankings, which Google itself says no one can do.

Sources

• Office for National Statistics: Internet sales as a percentage of total retail sales (J4MC)
• Shopify: SEO Basics for Ecommerce, A Beginner’s Guide (July 2026)
• Yoast: Ecommerce SEO, how to rank higher and sell more online
• Google Search Central: Ecommerce SEO best practices
• Google Search Central: Managing crawling of faceted navigation URLs
• Google Search Central: Designing a URL structure for ecommerce sites
• Google Search Central: Help Google understand your ecommerce site structure
• Google Search Central: Share your product data with Google
• Google Search Central: Product structured data
• Google Search Central: Do you need an SEO?
• Women in Tech SEO: SEO Essentials for Headless Commerce

Recommended

• Technical SEO Services: What They Include and How to Choose
• 5 ways to improve SEO on your ecommerce website
• The ROI of ecommerce SEO and paid advertising working together