Using MailerLite with WooCommerce: what works, what breaks

Quick answer

To connect MailerLite to WooCommerce, install MailerLite’s official WooCommerce plugin, paste in a MailerLite API key, choose the group new customers join, and switch on the checkout sign-up checkbox. It can sync customers and order data and run abandoned cart and post-purchase emails. Test consent, double opt-in and sync on a staging copy first.

Say a small online shop sells handmade soap through WooCommerce and wants three things: a newsletter sign-up at checkout, a reminder when someone leaves a full basket, and a thank-you email a week after delivery. MailerLite can do all three, and the connection takes under an hour. What catches people out is not the set-up but the details around it: who has actually agreed to receive marketing, what happens when the plugin and WordPress update, and which emails should never go through a newsletter tool at all. This guide covers both the steps and the snags.

What the integration does

MailerLite maintains an official plugin, MailerLite – WooCommerce integration, listed on WordPress.org. Its listing describes a checkout opt-in checkbox with an editable label, a double opt-in setting, abandoned cart emails, forwarding order data to MailerLite, product importing for campaigns, automations triggered by recent purchases and sales tracking. MailerLite’s own WooCommerce integration page says customers sync into a group you choose, connected with an API token.

Step 1: prepare before you install

• Take a full backup of the site, or work on a staging copy.
• Check versions. When we checked the plugin’s WordPress.org page in November 2026, it warned that it had not been tested with the latest three major releases of WordPress. That does not mean it fails, but it means testing matters.
• Decide your groups in MailerLite, such as “Shop customers” and “Newsletter subscribers”, so marketing consent stays clear.
• Write your consent wording for the checkbox, such as “Send me occasional emails about new soaps and offers”.

Step 2: install and connect

1. In WordPress, go to Plugins, search for the MailerLite WooCommerce plugin, install it and activate it.
2. In MailerLite, create an API key under the integrations or developer settings and copy it.
3. Paste the key into the plugin’s settings page in WordPress.
4. Choose the MailerLite group that subscribers from checkout should join.
5. If you want campaign sales tracking, create a WooCommerce consumer key and secret with read access, as the plugin listing describes, and add them.

Step 3: set up the checkout checkbox properly

This is the step with legal weight. In the UK, sending marketing emails to individuals generally needs their consent, with a limited exception for existing customers known as the soft opt-in. The ICO’s guidance on electronic mail marketing explains both.

• Leave the checkbox unticked by default, so ticking it is an active choice.
• Use plain words about what people will receive and how often.
• Decide whether to use double opt-in, which sends a confirmation email first; it reduces fake addresses and gives you a clear record.
• Make sure customers who do not tick the box still receive their order emails, which come from WooCommerce, not MailerLite.

Step 4: build the first automations

Check which of these your MailerLite plan includes before building them; plan features change, and the integration page does not list plan requirements.

Step 5: test everything end to end

1. Place a test order with the box ticked and another with it unticked.
2. Check the first customer appears in the right MailerLite group and the second does not.
3. Leave a basket with a test account and confirm the abandoned cart email arrives at the time you set.
4. Click the unsubscribe link and confirm the address is removed.
5. Check your order confirmation emails still arrive, unchanged.
6. Repeat the whole test on a phone, because many checkouts look different on a small screen and the checkbox can end up hidden below the payment button.

What commonly breaks

• Updates. A WordPress, WooCommerce or plugin update can change behaviour. Test after updates, ideally on staging, and keep backups; our WordPress maintenance guide sets out a safe routine.
• Custom checkouts. Checkout builders and some themes move or hide the checkbox. If it vanishes, sign-ups stop silently.
• Caching. Aggressive caching on checkout or basket pages can break basket tracking. Exclude those pages from caching.
• Old customers. Importing your whole past customer list into a marketing group without consent is a compliance risk. Only add people who agreed or who fall under the soft opt-in.
• Mixing email types. Order confirmations and password resets should not run through a newsletter tool. Our guide to transactional versus marketing emails explains why.

Make the emails look like your shop

Customers who just bought from a well-designed shop notice when the follow-up email looks like a generic template. Build one MailerLite template with your logo, colours and fonts, a clear header and a simple footer with your business details and unsubscribe link, and use it for every automation. Keep product images light so emails load quickly on phones, and write subject lines that sound like you rather than like a marketing department.

Review the results monthly. Look at how many abandoned baskets were recovered, how many people opened the thank-you email and whether unsubscribes rise after particular sends. Small changes, such as sending the cart reminder after a few hours rather than a few minutes, often matter more than redesigning the whole email.

When to get help

If MailerLite is not the right tool for you, our comparison of Mailchimp alternatives covers the main options, and our guide to email marketing for small businesses explains what to send. Our email marketing and automation set-up is £149 for campaigns, automation flows and segmentation. If the shop itself needs rebuilding, our e-commerce website starts at £499, and if visitors arrive but do not buy, read our guide to an online store with no sales. Every Luxbranding price is on our pricing page.