Build an ecommerce SEO selection checklist that survives scrutiny

What to take away

Decide first what evidence you will accept, then let that rule eliminate suppliers before price is discussed.
Test ecommerce SEO capabilitytechnical audits, structured data, Core Web Vitals and platform experience — before you compare price.
Size the addressable market with official data so you can judge whether a quote is proportionate to your store's opportunity.
Treat privacy duties and advertising policy as selection criteria, not afterthoughts.
Score every shortlisted provider on the same written checklist, and record who scored it and when.
Agree the exit terms, data handover and measurement baseline before any contract is signed.

Size the market first

Start with the number of businesses you are competing against for attention and budget. The Office for National Statistics publishes business demography statistics for the UK, which gives you a defensible figure for how crowded your category is. Use it to frame the brief, not to justify a spend.

Official count tests coverage claims

ONS business demography statistics

Use to frame the brief

Not to justify a spend

Test supplier market coverage claims

A figure from a national dataset will not tell you what your store should pay. It tells you whether a supplier's claim about market coverage is plausible. If a provider says it works with most of your competitors, the official count lets you test that statement in one sentence.

Check privacy and tracking duties

Any supplier that touches analytics, pixels or customer records must show how it handles personal data. The Information Commissioner's Office sets out designing products that protect privacy, which is the standard to hold a provider to when it proposes new tracking.

Ask which lawful basis the supplier relies on under UK GDPR, and how consent for analytics and advertising pixels is collected under PECR. A provider that cannot describe the consent banner, the tags that fire before consent and the retention period in writing has not thought about your risk.

Privacy and tracking duties

Show how personal data is handled
Meet ICO privacy design standard
Provide the data map in writing
Treat verbal assurance as the answer
Record answers side-by-side

Ask for the data map in writing. If the answer is a verbal assurance, that is your answer. Record each answer in a side-by-side table so that every supplier is judged on the same evidence.

Run the numbered checks

Use the same sequence for every supplier so the comparison is fair.

Confirm the legal entity on Companies House and note the registered address.
Request two written references from stores of a similar size, not logos on a slide.
Ask for the measurement baseline it will use in month one.
Test whether it can explain a past underperformance without blaming the client.
Check who owns the accounts, tags and content once the contract ends.
Agree the notice period and the data handover format.
Set a review date at 90 days with written success criteria.

Each step produces a document. A supplier that cannot supply one is a risk you are choosing to carry.

Checks that test ecommerce SEO, not general procurement

The seven checks above filter out suppliers that cannot run a contract. These test whether a supplier can do the work on a store.

Crawl and indexationask how it will handle faceted navigation, filter parameters and pagination across your catalogue, and ask it to crawl your store with a tool such as Screaming Frog as a first task.
Core Web Vitalswhat it will change on category and product templates to improve Largest Contentful Paint, Interaction to Next Paint and Cumulative Layout Shift, and how it will confirm the result in Google Search Console.
Category and product pageshow it writes titles, headings and copy across hundreds of SKUs without producing thin or duplicated pages.
Structured datawhich schema.org types it will add — Product, Offer, Review and Breadcrumb — and how it validates them.
Platform competencethe platforms it has actually worked on, such as Shopify, WooCommerce, Magento (Adobe Commerce) or BigCommerce, and what that means for template, checkout and app limits.
Feeds and Merchant Centerif you sell on Google Shopping, how it handles feed titles, attributes and disapprovals.
Migrationsthe redirect map, staging process and launch checks it uses when a store changes platform or domain.
Measurementthe accounts it will work in — Google Analytics 4 and Google Search Console for traffic and revenue, a rank tracker such as Ahrefs or Semrush for positions — and the report it will produce, covering non-brand organic revenue, organic sessions, rankings and conversion impact.
Deliverablesthe technical audit, content plan, link building and digital PR you are buying, with the format and frequency of each.

Score the evidence, not the pitch

Give each check a score and a short note. Price enters the score last, after capability and risk. A cheaper quote that fails checks one, five and six is not cheaper.

Keep the scoring sheet with the contract. If performance is disputed later, the sheet shows what was agreed and what was assumed. Weight the checks to your own priorities, and resist turning a score into false precision.

Advertising policy checks

If the supplier will run paid search alongside organic work, it must follow platform rules. Google publishes best practices for search campaigns covering account structure, keywords and landing pages. Ask how the provider applies them to your store.

Policy breaches cost money and time. A supplier that cannot describe its approval process for ad copy and landing pages is a liability, particularly where regulated products are sold. For those products, the Advertising Standards Authority's CAP Code governs the claims you can make in ads and on landing pages, so ask who checks the copy against it.

Contract and exit terms

Write down who owns the domain, the analytics property, the tag manager container and the content. Ownership should sit with your business, not the agency. For example, a team paying £2,500 a month for twelve months is committing £30,000, so the exit terms matter as much as the deliverables.

Include a clause on subcontractors. If work is passed to a third party, you need to know before it happens, not after. Add a clause on data deletion at termination and a named contact for the handover.

Common questions

The questions below come up most often when stores compare ecommerce SEO suppliers.

How many suppliers should I score?

Three to five is usually enough to see a pattern without burning weeks. Score them on the same sheet, and keep the notes even for the ones you reject.

Do I need a lawyer to review the contract?

For anything above a few thousand pounds, yes. A solicitor can check ownership, liability and termination clauses faster than you can learn the risks.

What if the supplier refuses to share references?

Treat it as a failed check. You can still proceed, but record the decision and the reason so the choice is documented.

How often should the checklist change?

Review it annually, or sooner if privacy rules or platform policies change. A checklist that never changes stops testing anything.