Email marketing agencies for ecommerce brands

Most of the work happens inside the email platform, which for a Shopify or WooCommerce store is often Klaviyo, Omnisend or Mailchimp. A good agency connects the store so that every product view, basket and order reaches the platform, builds segments such as first-time buyers, repeat customers and people who have gone quiet, writes and designs each email in the brand's own voice, and reports what each flow and campaign earned.

Flows earn far more for each email sent than campaigns do. In Klaviyo's 2026 benchmarks, flows produced nearly 41% of email revenue from just 5.3% of the emails sent, because each one reaches a shopper at the moment they have shown what they want.^[1]

Demand for this kind of agency is far higher in the US than in the UK. The work is the same in both markets; what differs is the law on consent, covered in the last answer on this page.

Revenue per recipient is the fair way to compare flows, because it counts everyone the flow reached, whether they opened or not. Abandoned basket flows also convert best: on average 3.33% of the people who receive one place an order, and the top 10% of brands reach 7.69%.^[3]

Replenishment and win-back only work when their timing comes from your own orders. A replenishment email should land when the product runs out, which you can read from the gap between customers' first and second orders of it. A win-back should fire once a customer is past the point where most of your repeat buyers come back. The default timing in a template is a guess.

Deliverability is the question that separates careful agencies from the rest, because the big mailbox providers have tightened their rules. Google requires everyone who sends to Gmail to keep the spam rate reported in Postmaster Tools below 0.3%, and advises staying below 0.10%. Anyone sending more than 5,000 messages a day to Gmail accounts must also set up SPF, DKIM and DMARC and offer one-click unsubscribe.^[5]

The law on consent differs between the two markets. In the UK, the ICO says you must not send marketing emails to individuals without specific consent, apart from a limited exception for your own previous customers known as the soft opt-in. In the US, the CAN-SPAM Act sets out what every commercial email must carry, including an opt-out that is honoured within 10 business days, and the FTC says each email that breaks it can draw a penalty of up to $53,088. Klaviyo's own acceptable use policy bans sending to purchased, rented or borrowed lists wherever you are.^[6][7][8]

Then decide how broad the help should be. An email-only agency goes deep on flows and design, which suits a brand whose ads and site are already in good hands. If the list is small because too few people reach the store, better emails cannot fix it; the work that matters sits in the ads and the pages that bring people in.

That link is why we run email as one part of marketing for ecommerce brands. Capture, abandonment, post-purchase, cross-sell, replenishment and reactivation flows sit alongside the Meta and Google ads and the product and landing pages that fill the list, a person writes and checks every email, and you approve each one before it goes live. Our published client results are in paid media and automation rather than email on its own, so the fairest test of our email thinking is the free breakdown.