Best ecommerce SEO agencies in 2026: 12 ranked

The most experienced ecommerce-only shop on this list, and it shows on large catalogues — faceted navigation, crawl budget, parameter handling, the unglamorous work that decides whether 40,000 SKUs get indexed. They have moved into AI-search work for product and category pages too. Expect agency pricing and a page-production rate set by headcount rather than by how many categories you have.

Inflow runs SEO, paid and conversion work as one program rather than three invoices, which is the right shape for a store where a 0.3% conversion lift is worth more than another 5,000 sessions. Senior strategists stay on the account. It is a considered, mid-to-upper-market engagement, and content output is deliberate rather than high.

A large agency with a deep bench across Shopify, Magento and BigCommerce, plus design and development in-house. Useful when the SEO fix requires a template change and you would rather not coordinate two vendors. The size cuts both ways: plenty of capacity, but your account manager may be running several stores at once.

One of the few agencies here that will work without a long-term contract, which matters if you have been burned by a twelve-month term and a quarterly report. Strong fundamentals and good client retention. Content depth is moderate, and the practice spans local as well as ecommerce, so the specialisation is thinner than OuterBox or Inflow.

A big, well-regarded agency with a substantial ecommerce practice covering SEO, paid, email and social. A sensible pick if you want one vendor across every channel a DTC brand runs. Ecommerce is one of several practices, so the depth on catalogue-specific technical work is behind the specialists, and pricing sits at the top of the range.

A large full-service agency with a long list of ecommerce accounts and clear, readable reporting. Reasonable for mid-size stores that want competence without a boutique price tag. The approach is standardised, which is efficient but means less of the bespoke category-architecture thinking a big catalogue needs.

Highly reviewed, very large, and a low-risk choice for a store that wants solid execution and a lot of public feedback to check first. Good on the basics: product titles, schema, site speed, PPC alongside. Less strong on the deep content programmes that win category and buying-guide terms.

For a DTC brand fighting Amazon and three marketplaces for the same product terms, links are often the missing ingredient, and Siege earns them with original research and designed assets rather than outreach spam. Campaigns cost real money per placement, and ecommerce is one of several verticals.

A technical Shopify Plus partner where SEO sits next to ongoing platform development. Genuinely useful if your problems are theme-level — rendering, speed, collection templates. Treat it as engineering support with SEO attached rather than a content programme; the writing side is minimal.

One of the more accessible entries here, aimed at smaller stores that cannot justify a five-figure retainer. Straightforward keyword, on-page and link work with responsive communication. The output is proportional to the price, so expect steady incremental progress rather than a step change in coverage.

A sizeable cross-channel agency covering SEO, paid, Amazon and creative for retail brands. The multi-marketplace angle is the draw — few agencies think about your Amazon listings and your own site together. Ecommerce SEO specifically is one line inside a wide offer, and pricing reflects the full package.