What Is Email Marketing and How Does It Work
Email marketing is the channel through which an online store communicates directly with its subscribers and customers, using emails sent automatically or on a schedule, in order to sell, inform and keep the relationship going after the first order. Unlike paid ads, where you pay every time for access to an audience that doesn't belong to you, here you talk to a list you built yourself and own.
Email marketing is commercial communication sent by email to people who have agreed to receive it. In an online store, it breaks down into campaigns sent manually, automated flows triggered by user behavior, and transactional messages tied to an order.
How does it work, step by step?
The mechanism has four stages. The first is collecting subscribers: visitors leave you their email address through a form, a pop-up, a placed order or a waitlist signup, always with explicit consent. The second is storing and organizing those contacts in an email marketing platform, together with the behavior data the store sends: products viewed, orders placed, lifetime value, preferred categories.
The third stage is the sending itself, which splits into two completely different types: campaigns, meaning messages sent manually at a time you choose, and automated flows, meaning messages triggered by a user action and sent with no human intervention. The fourth stage is measurement: every message generates data on delivery, opens, clicks, unsubscribes and attributed orders, and that data feeds back into segmentation and your next decisions.
How is email marketing different from paid ads?
The key difference is ownership of the audience. With ads, you rent attention: the moment you stop the budget, the traffic disappears too. With email, you own the channel: the list stays yours, and the cost of one more message to an existing subscriber is marginal, no matter how expensive the auction has become on advertising platforms.
| Criterion | Paid ads | Email marketing |
|---|---|---|
| Audience | Rented from the platform | Owned by the store |
| Cost of an extra message | Rises with volume and auction prices | Marginal, regardless of volume |
| What happens without budget | Traffic disappears immediately | The channel keeps working |
| Available data | Limited by thresholds and privacy rules | Full order and browsing history |
| Main role | Brings in new customers | Grows the value of existing customers |
The two don't compete, they complement each other. Paid ads bring in new people, email turns them into customers and brings them back. A healthy email program reduces your dependence on acquisition cost and improves the economics of the whole store, because the same customer's second and third orders come without paying for the click again.
What types of emails does an online store send?
A complete program has three categories of messages, each with a distinct role:
How you distribute your effort matters more than volume. Campaigns take time every week, while flows are built once and work permanently, for every visitor who enters the store. That's why, in a mature program, a large share of email revenue comes from automations, not from manual sends.
What is an automated flow and why does it matter?
A flow is a sequence of messages tied to a trigger condition. Someone adds a product to their cart and doesn't complete the order; after a set interval, they receive a first reminder, then, if they still don't buy, a second message with a different angle. Every step has an exit condition: if the person places the order, the sequence stops.
How do you build a healthy subscriber list?
A healthy list means contacts who have given their consent, who are active and who recognize the sender. It is built slowly and destroyed quickly, through purchased lists or importing addresses without consent. The practical levers are:
- A visible signup form on the site and a pop-up triggered by exit intent or time spent on the page.
- A clear reason to sign up: access to launches, a useful guide for your category, stock notifications, a benefit on the first order.
- Collecting consent at checkout, separate from acceptance of the terms and conditions.
- List hygiene: regularly removing addresses that haven't interacted in a long time and those that cause permanent delivery errors.
What role does segmentation play?
Segmentation means splitting the list into groups by behavior and by relationship with the brand, so you don't send the same message to a loyal customer and to a subscriber who has never bought. Useful criteria are the recency of the last order, order frequency, lifetime value, the product category purchased and the level of engagement with previous messages.
Segmentation has a double effect. In the short term, it increases relevance and, with it, the conversion rate of every send. In the long term, it protects your sender reputation, because you email people who don't open less often, and email providers read that as a positive signal.
Why does deliverability matter before anything else?
Deliverability is the ability of your messages to reach the inbox, not spam or the promotions tab. It is the baseline condition: a well-written email with a good offer produces nothing if nobody sees it. The elements that affect delivery are:
- Domain authentication through SPF, DKIM and DMARC, fully configured in the DNS settings.
- The reputation of the domain and of the addresses used for sending.
- List quality: the share of nonexistent addresses and of contacts who no longer interact.
- Sending frequency and the rate of complaints reported by recipients.
When you start a new sending domain or switch platforms, increase volume gradually, starting with the most active segments, so that email providers collect good signals before the large sends.
What platforms are used for email marketing?
Choosing a platform depends on catalog complexity, contact volume and the need to integrate with the rest of your stack. At BigConvert we work in three directions: Klaviyo, for stores that need advanced behavioral segmentation and native integrations with eCommerce platforms; TheMarketer, a Romanian omnichannel platform with predefined flows and access suited to the local market; and an in-house sending system, used where control over infrastructure, volume and cost per message matters.
Which metrics should you actually track?
Open rates have become a rough indicator, because of privacy protection mechanisms that preload the images in messages. The metrics that decisions are based on are different:
- Click rate and click rate relative to delivered messages.
- Revenue per recipient, which normalizes the result regardless of segment size.
- The share of flows in total email revenue, as an indicator of the program's maturity.
- Unsubscribe rate and complaint rate, as long-term health signals.
How do you know if your email program is profitable, not just productive?
The revenue reported by the platform tells only half the story. A message that sells low-margin products, backed by a generous discount, can look excellent in the revenue report and contribute very little to profit. That's why we measure the channel through POAS, meaning profit relative to promotion spend, not just revenue relative to spend.
How do you start an email marketing program from scratch?
The right order of work is the same for most stores: technical setup first, then automations, then campaigns.
- Set up domain authentication and the platform's integration with the store, so that behavior data flows correctly.
- Build the subscriber collection mechanisms and the basic segments.
- Launch the flows with immediate impact: welcome, abandoned cart, abandoned checkout, post-purchase.
- Add the campaign calendar, and only then move on to secondary flows and systematic testing.