Automations
Emails that go out by themselves: Welcome, Post-purchase, Win-back, Abandoned cart, Back in stock and Birthday.
Updated October 31, 2026
Automations are emails that go out by themselves when someone subscribes, buys, has not bought in a while, or leaves items in their cart. SendDuo comes with six ready-made automations. Each one already has its emails written; you check them, change what you like, and turn it on.
Welcome
Starts when someone subscribes: through one of your sign-up forms, through your store's checkout opt-in, when you add them by hand, or in an import when you tick the Welcome box.
- A welcome email straight away.
- 2 days later: "Our story".
- 3 days after that: "A little welcome gift" with a discount code.
Post-purchase
Starts when a paid order comes in from your store.
- 1 day later: "Thank you" for the order.
- 9 days after that: "How was it?", asking for a review.
- 11 days after that: "You might also like", with products you pick.
Win-back
Starts for subscribers whose last paid order was a set number of days ago (90 unless you change it). Each person gets it once each time they lapse.
- "We miss you", with a discount code.
- 7 days later: "Last chance", a reminder of the code.
Abandoned cart
Starts when a subscribed shopper leaves items in their cart and does not order within the time you choose. It ends when they order or empty the cart. Each person gets it at most once a week.
- "You left something behind", showing what is in the cart.
- 20 hours later: "Still thinking it over?".
- 2 days after that: "A little something to help you decide", with a discount code.
Back in stock
Starts when a product is back in stock for shoppers who asked to be told. On a sold-out product page, shoppers type their email under "Sold out. Email me when it's back." and can tick "Also send me news and offers" to join your list too.
- "It's back", showing the product's picture, name and price.
Each request gets this email once. It goes to everyone who asked, whether or not they subscribed to your news, because they asked for it. Requests not fulfilled within 6 months are dropped. The flow page lists the products people are waiting for, so you can see what to reorder.
On WooCommerce, the SendDuo plugin (version 1.0.7 or later) shows the box on sold-out product pages by itself; you can switch it off in the plugin's settings. On Shopify, add the SendDuo back in stock block to your product page in the theme editor. It shows only while every variant of the product is sold out.
Birthday
Starts in the morning (9:00 in your time zone) for subscribers with a birthday saved. On the flow page, Send it chooses the day: on their birthday, or 1, 3 or 7 days before, so they have time to use a code.
- "Happy birthday", with a discount code if you offer one.
Each person gets it once a year. Birthdays come from sign-up forms with Ask for a birthday switched on, a Birthday column in a CSV import, or the contact's page. Only the month and day are kept. February 29 birthdays get theirs on February 28 in other years.
What each automation needs
- Welcome works without a store.
- Post-purchase and Win-back need a connected store, because they use your orders.
- Abandoned cart needs a connected Shopify store, or WooCommerce with the SendDuo WordPress plugin installed and connected. The plugin is what tells SendDuo about carts on WooCommerce.
- Back in stock needs a connected Shopify store, or WooCommerce with both the store connection and the SendDuo plugin (1.0.7 or later), because it watches your products' stock.
- Birthday works without a store; it needs your contacts' birthdays.
See Connect Shopify or Connect WooCommerce.
Turn an automation on
- Open Automations.
- Click Edit flow to check the emails and settings first.
- Click Turn on.
If something is missing, such as your sender details, a verified domain or a connected store, the flow page tells you what to fix before you turn it on.
Turn off stops the automation. Anyone partway through it does not get their remaining emails.
Offer a discount code
Welcome, Win-back and Abandoned cart each have an email with a discount code. On the flow page, the Offer a discount code switch decides what happens:
- On: type the code in Discount code and click Save. Create this code in your store first; SendDuo puts it in the emails but does not create it for you. Use letters, numbers, dashes or underscores, up to 40 characters.
- Off: the emails go out without a code. An email that is about the code (its subject names it) is skipped, and in the other emails the part that shows the code is left out.
In an email, {{discount_code}} shows the code. It only works in automations, not in campaigns.
Abandoned cart timing
On the Abandoned cart flow page, Send the first email after sets how long a cart sits without activity before it counts as abandoned: 1, 2, 4, 6, 12 or 24 hours. 4 hours is recommended and suits most shops.
Win-back timing
On the Win-back flow page, Days without an order sets when a customer counts as lapsed. Choose between 30 and 365 days. The default is 90.
Edit the emails and steps
- On the flow page, click Edit email on any email.
- Change the content in the editor, the same way as in a campaign. Changes save by themselves.
- Change the Subject or Preview text and click Save settings.
- Use Send a test to see it in your inbox. Order details use sample values.
Back on the flow page, use + Add email and + Add wait to add steps, and Remove to take one out. A wait can be up to 720 hours or 365 days, and a flow can have up to 20 steps. When you remove an email, people waiting for it move on to the next step.
Each email shows how many were sent, delivered, opened and clicked, how many people unsubscribed and, with a connected store, the revenue.
One automated email a day
Nobody gets more than one automated email a day, across all your automations. An email due on a day the person already got one waits until the next day. When two are due the same day, the Abandoned cart email goes first.
All buyers or Subscribers only
In Post-purchase, each email has a Who gets this email choice:
- All buyers: everyone who ordered, including customers who did not subscribe. Use it only for messages about their order, with no discounts or product promotions. "Thank you" and "How was it?" start this way.
- Subscribers only: only people who subscribed to your emails. "You might also like" starts this way, because it shows products.
All the other automations go to subscribers only.
When you run out of emails
Automated emails count toward your monthly allowance. If it runs out, they wait and go out when your allowance resets, or as soon as you upgrade or buy an email pack. See Plans and billing.