Email Marketing for eCommerce: What Your Store Should Actually Run

Email marketing for an eCommerce store is the program of automated flows, scheduled campaigns and list growth that turns your subscribers into first-time buyers and your first-time buyers into repeat customers. Hayes Media, an eCommerce growth agency for DTC and Shopify brands, builds email programs in three parts: flows first, then campaigns, with list growth feeding both.

This page covers what the program is made of and what to set up first. If you're weighing outside help and want to know what an agency does and how to pick one, read our guide to hiring an eCommerce email marketing agency.

What does eCommerce email marketing actually include?

It includes three parts that work together. Each one has a different job, and a store that runs only one of them leaves the other two jobs undone.

Flows. Automated emails that send when a shopper does something, like joining your list, leaving a cart or placing an order. They run every day without anyone pressing send.

Campaigns. Emails you plan and schedule to a list or segment on a date you pick: launches, restocks, sales, stories and news.

List growth. The forms, offers and opt-ins that bring new subscribers in. Without it, flows have no one to trigger for and campaigns go to the same people every week.

Segmentation and testing sit across all three parts. Segments decide who gets what, and tests tell you which version to keep. Email is also one channel inside a wider retention program. Hayes Media's retention practice covers email, SMS, loyalty programs and subscribe-and-save, but email on its own is a complete program and a complete engagement.

What's an email flow, and which flows should go live first?

An email flow is an automated sequence that starts from a shopper's action and sends on a schedule you set. Klaviyo's help center defines it as "a sequence of automated actions (e.g., sending messages) triggered by a behavior or event."

Klaviyo also gives a starting order: "The most impactful flows are also the ones you should set live first." Its list, in order, is welcome series, abandoned cart, post-purchase and winback. We build in the same order for a new account, because each one covers a moment every customer passes through.

Welcome series. Klaviyo describes it as a flow that "introduces subscribers to your brand and converts them into first-time customers." It's the first thing a new subscriber gets, so it carries your story, your best sellers and the reason to buy now. Our welcome series guide breaks down what goes in each email.

Abandoned cart. This flow catches shoppers who added something and left. Klaviyo notes it's "customizable based on items in someone's cart and whether they're already a customer." See our abandoned cart email examples for how we write and order those messages.

Post-purchase. This flow follows the first order with thanks, how to use the product and what to try next. It's where you set up the second order. Our post-purchase email flow examples show the full sequence.

Winback. This flow goes to past buyers who've gone quiet. Klaviyo says it "re-engages customers who purchased in the past, but haven’t bought again in a while." Time it to your own product's purchase cycle, not a template's default.

Every flow needs an exit rule so a shopper stops getting it once they've done the thing you wanted. In Klaviyo, profile filters do this job: "When each message is scheduled to send, Klaviyo will apply your profile filters again (e.g., has Placed Order zero times since starting this flow) and skip anyone who fails these filters at send time." Once the first four are live, browse abandonment, replenishment and others come next. Our list of the Klaviyo flows every store needs covers each one and its job.

How do campaigns and flows split the work?

Flows handle the moments every customer goes through, on each person's own timing. Campaigns handle what's new in your store, sent to a chosen group on a chosen day. You need both, and they shouldn't try to do each other's job.

A flow doesn't know you're launching a new color next Tuesday. A campaign doesn't know that one shopper left a cart ten minutes ago. So flows stay evergreen and get reviewed on a set rhythm, while campaigns follow your calendar: launches, seasonal sales, restocks, founder notes and content that gives people a reason to open when there's no offer.

The main risk is overlap. If a shopper is in your welcome series and also gets three campaigns that week, they're hearing from you a lot in their first days on the list. We handle that with send rules and segments, so new subscribers and recent buyers get fewer campaigns while their flows run. When you send matters too, and our guide to the best time to send email explains how to test it on your own list rather than copying someone else's.

Where does list growth fit into email marketing?

List growth is the input for everything else. Flows only trigger for people who join, and campaigns only reach people on the list, so a program with a weak sign-up rate stalls no matter how good the emails are.

The work is the sign-up form, the offer or reason to join, where the form shows on your site, and a separate opt-in for SMS. Klaviyo recommends separate welcome flows for each channel, "since subscribers can opt in to email and SMS separately and each welcome series flow can only be entered once."

What you offer at sign-up shapes who joins. If the only reason to subscribe is a discount, your welcome series has to work harder to sell at full price later. A quiz, early access or a useful guide gives people a reason to join that's about the product itself. Hayes Media's retention site says "We grow client lists 3.1x faster." That figure is published by Hayes on its own site.

How do segmentation and testing fit in?

Segmentation decides who gets each message, and testing decides which version you keep. Both make the same emails earn more without sending more of them.

Klaviyo defines a segment as "a dynamic grouping of profiles that meet certain criteria." Profiles move in and out as their behavior changes, so a segment like "bought twice, nothing in the last cycle" stays current on its own. Segments can also start flows, and inside a single email, Klaviyo's conditional tags "allow you to include content in your messages for recipients who meet certain criteria, and not include it for others." That lets one send show first-time buyers and repeat buyers different blocks.

Test one thing at a time: a subject line, an offer, the order of emails in a flow. Judge the result on orders and revenue per recipient, since an open on its own doesn't pay for anything. If a list is too small to give a clear answer, run the test longer or test bigger changes.

How do you judge whether your email program is working?

Hayes Media judges email on lifetime gross profit to CAC, with revenue from retention as the main email number underneath it. CAC is what you pay to acquire one new customer. Lifetime gross profit is the margin one customer returns across their whole life with you.

Email moves the top half of that ratio. Every repeat order adds gross profit without a new acquisition cost, so a stronger program raises what each customer is worth and what you can afford to pay for the next one. Loyalty starts before the first order, in the whole buying experience, and the second order is where it shows in your numbers. For the full set of numbers to track and how to calculate each, see our guide to customer retention metrics.

On Hayes Media's retention site, one account shows "0% to 59% of Revenue from Retention", "+140% Total Revenue YoY" and a "54% Returning Customer Rate". Those figures and our case studies are published by Hayes on its own sites. Hayes has no third-party review profile and no Klaviyo partner listing.

What does that look like with real numbers?

These are made-up numbers to show the mechanism, not results from a client or a benchmark. Say your CAC is $40 and your first order earns $30 in gross profit. You acquire 100 customers for $4,000, and their first orders return $3,000.

Before. Your flows are thin. Of those 100 customers, 30 place a second order and 12 place a third, each earning $30 in gross profit. That's $900 plus $360, so lifetime gross profit across the group is $4,260, or $42.60 per customer. Against a $40 CAC, the ratio is 1.07.

After. You fix the post-purchase and winback flows and segment your campaigns. Now 40 customers place a second order and 18 place a third. That's $1,200 plus $540, so the group returns $4,740, or $47.40 per customer. The ratio rises to 1.19 with the same ad spend and the same CAC.

In this made-up case the gain came entirely from orders the brand had already paid to make possible. That's why we look at email in lifetime gross profit, not only in revenue attributed to the last email clicked.

When doesn't this approach apply?

You don't have the product right yet. If customers don't like what they bought, no flow will bring them back. Fix the product and the buying experience first.

Your product is a one-time purchase. If people buy once in a long while, repeat revenue won't carry the program. Lean on the welcome series and abandoned cart, and judge email on first-order conversion more than retention share.

Your volume is too low to test. With few orders, test results won't tell you much. Set the four core flows live, send steady campaigns, and save testing until there's enough data to read.

You only want discount blasts. If every send is a sale, you're training people to wait for the next one. The program above needs room for emails that sell without a code.

How does Hayes Media run eCommerce email marketing?

Hayes Media builds and runs retention for eCommerce brands: email, SMS, loyalty programs and subscribe-and-save. We work in Klaviyo for most accounts and have experience in most other email and SMS platforms, so a brand on another platform is still a fit. Email on its own is a full engagement, and you can see how our email and SMS service works.

Hayes Media's retention site lists "8 yrs Retention expertise", "$500M+ Client revenue driven" and "15x Average ROI". As above, these are self-published, and Hayes has no third-party review profile or Klaviyo partner listing.

Hayes Media works with brands doing at least $100K per month in revenue. It's a guideline, not a gate: a smaller brand with a clear budget set aside to scale and real order volume already qualifies. One-time email projects start from $2,000 USD, and retainers for ongoing full management start from $4,000 USD per month, scoped on the discovery call.

If you want to know which flows you're missing and where your campaigns overlap them, we'll audit your email program on the call and show you what to fix first. Book a discovery call. No onboarding fees. No lock-in contracts. No junior marketers.

Sources

Klaviyo Help Center: Getting started with flows. Source for the flow definition, the suggested first flows and their order, profile filters at send time, segment definition, and separate email and SMS welcome flows.

Klaviyo Help Center: Message personalization reference. Source for conditional tags in messages.

Hayes Email and Retention. Source for Hayes Media's retention figures and terms.