What an email marketing agency does for an ecommerce brand
An email marketing agency plans, builds, and runs the flows and campaigns that turn your existing customer list into repeat revenue. For ecommerce brands that means Klaviyo setup, automation flows, segmentation, and a campaign cadence, run as one connected system instead of a checklist of one-off sends.
Most brands don't have an email problem. They have an ownership problem. Someone set up a welcome flow two years ago. Nobody's touched segmentation since. Campaigns go out when there's time, not on a plan tied to what customers actually buy and when. Those neglected flows are where the revenue hides: automated emails drove 37% of all email-generated sales in 2024 while making up just 2% of email volume (Omnisend 2025 Ecommerce Marketing Report).
We run this as a retainer, not a project. Platform setup and first sequences upfront, then an ongoing cadence: campaigns planned against your product calendar, flows checked and rebuilt as your catalogue changes, segmentation that gets sharper as we learn more about who's actually buying.
The work is ESP-agnostic (we'll run this on Klaviyo, HubSpot, ActiveCampaign, or Brevo depending on your existing stack), but for ecommerce and DTC brands specifically, Klaviyo is the default. It's built for the exact retention mechanics this page is about: purchase-based segmentation, product-level flow triggers, revenue attribution per email.
Why retention beats another round of ad spend
Every pound spent scaling paid ads gets more expensive as you go. A retention engine works the other direction: it makes each customer worth more over time, which is what keeps acquisition sustainable.
Ad accounts don't scale in a straight line. Spend goes up, cost per result goes up with it, and at some point ROAS stops cooperating no matter how good the creative is. That's not a Meta problem or a Google problem. That's what happens when the only lever you're pulling is acquisition.
Retention is the lever most established brands underuse. A customer who's already bought from you is cheaper to sell to again than a stranger is to acquire for the first time, and email is the channel where that repeat sale actually happens on your terms, not an algorithm's. We wrote the longer version of this argument in retention beats acquisition: the short version is that a brand plateauing on ROAS almost never needs a bigger ad budget first. It needs the retention side of the engine built out.
That's the same reason this sits inside our wider marketing work, not off to the side of it. See the wider marketing engine for how email connects to paid, content, and SEO.
What we actually build in Klaviyo
Welcome sequences, abandoned-cart and browse-abandonment flows, post-purchase and win-back automations, VIP and loyalty segmentation, and a weekly or biweekly campaign cadence. Named flows, not a vague "automations" promise.
Welcome and positioning sequence
The first emails a new subscriber gets set the relationship. Not a discount code and silence. A sequence that tells them who you are, why the product's worth what it costs, and what to expect next.
Abandoned cart and browse abandonment
Someone added to cart and left. Someone looked at a product three times and didn't buy. Different intent, different message, different timing. Both get built, both get tested.
Post-purchase and win-back
The highest-intent moment you'll ever have with a customer is right after they buy. And the best moment to save a customer who's drifting is before they've fully gone quiet, not after. Both flows exist because both moments get ignored by default.
Segmentation and list hygiene
A list that's never been segmented treats a first-time buyer the same as someone on their tenth order. That's a wasted list. Segmentation by purchase history, recency, and engagement is what makes every other flow and campaign actually relevant instead of generic.
Email and content, run as one system
Email doesn't work in isolation from content or paid. The strongest retention engines feed off the same customer insight the rest of the marketing engine runs on.
An email calendar that's disconnected from what you're publishing everywhere else is a missed opportunity twice over: content with nowhere to go after it's made, and email with nothing fresh to send. We've made this case in more detail in content and email, run as one system, not two vendors, and it's the same discipline behind a marketing engine that compounds: one team, one stack, one plan, not a pile of vendors each optimizing their own slice.
How pricing works
A setup fee covers platform build, templates, and your first sequences. A monthly retainer covers ongoing campaigns, flow maintenance, and reporting, scoped to a send cadence, not a vague "email management" line item.
We don't publish exact numbers here, because the right scope depends on your list size, your catalogue, and where your flows already stand. What we will tell you upfront is the pattern: a setup fee for the initial build, then a monthly retainer tied to a defined cadence, reviewed monthly against real numbers, not a dashboard full of opens and nothing else.
If the scope changes, we tell you before it changes, not after the invoice.
Email is the channel you already own. No algorithm decides who sees it, no bidding war decides what it costs. Most brands treat it like an afterthought anyway, and it shows: three flows nobody's touched, a list that's never been segmented, campaigns that go out when there's time instead of on a plan.
We build this as an engine, not a checklist. Retention that makes your acquisition spend go further, run by the same team that runs the rest of your marketing, reporting on revenue, not opens.
↳ Frequently asked
01What does an email marketing agency actually do?
An email marketing agency builds and runs the automated flows and scheduled campaigns that sell to your existing customer list. That includes platform setup, template design, segmentation, welcome and post-purchase sequences, abandoned-cart recovery, and ongoing campaign planning, reported against revenue, not just opens.
02Why use Klaviyo instead of Mailchimp or another platform?
Klaviyo is built specifically for ecommerce: it ties directly into Shopify (and most major platforms) for purchase data, product triggers, and revenue attribution per flow and per email. General-purpose tools like Mailchimp can send email well, but they weren’t built around ecommerce purchase behaviour the way Klaviyo was. For non-ecommerce brands, a different platform can be the right call.
03How much does email marketing cost with an agency?
Most agencies, including ours, work on a setup fee plus a monthly retainer, with the retainer scoped to send cadence and flow complexity rather than a flat rate. Expect the setup to cover platform build and your first sequences, and the monthly fee to cover ongoing campaigns, maintenance, and reporting.
04How long before email marketing shows results?
Flows built on existing traffic (abandoned cart, welcome, post-purchase) typically start generating revenue within the first few weeks, since they're triggered by behaviour that's already happening. Campaign performance and list growth compound more slowly, usually over a few months, as segmentation sharpens and the list itself grows.
05What's the difference between email marketing and retention marketing?
Email marketing is a channel. Retention marketing is the goal that channel serves, alongside SMS, loyalty programmes, and repeat-purchase incentives. In practice, for most ecommerce brands, email is the primary retention channel, but "retention marketing agency" describes the strategic job; "email marketing agency" describes the main tool used to do it.
06Do I need a big email list before this is worth it?
No. What matters more than list size is whether you have repeat-purchase behaviour worth capturing. A smaller list with strong product-market fit often outperforms a large, unengaged one. We'll tell you honestly in a strategy call if your list isn't ready yet, rather than take the retainer anyway.