What is a win-back campaign?
How does a win-back campaign work?
A customer buys. Time passes. They do not come back. After a set period, they enter a short sequence of emails or messages, for example a reminder, an offer and a last call. If they respond, they return to normal communication. If they do not, many teams stop writing to them. That stopping rule is an email sunset policy.
The same vendor guide describes a four-email sequence, followed by a sunset step that moves non-responders to a suppression list1. We would add one rule: end it, do not let it run for ever.
When is a customer "lapsed"?
That depends on what you sell. A shop selling coffee has a different rhythm from one selling mattresses. A vendor guide to ecommerce churn, which is customers lost over a period, suggests that, without subscriptions, you set the window from your own average time between repeat orders2. See churn.
So a fixed cut-off copied from another shop is a guess, unless it fits your product. Look at the gaps between orders for your own customers. RFM analysis groups customers by how recently, how often and how much they bought, and is one way to find those gaps.
Did the campaign win anyone back?
Not necessarily. Some customers on your lapsed list were about to buy anyway. If they order after the email, the email gets the credit. Whether it caused the order is the question of incrementality, usually settled with a holdout: a group that does not get the campaign.
Also check margin. A win-back offer can bring back orders that cost more in discounts than they earn.
For ZFD: A win-back order counts only if it would not have happened anyway. See customer retention strategy ecommerce. For when to try again and when to stop, read win-back email campaign ecommerce.
Easily confused with
Win-back campaign vs Abandoned cart flow
For people who started a checkout. A win-back is for people who bought before and went quiet.
Win-back campaign vs Churn
A rate of customers lost over a period. A win-back is one attempt to reverse it.
Win-back campaign vs Email sunset policy
The rule for when to stop emailing people who do not engage. It is often the last step of a win-back sequence.
FAQ

How long should I wait before a customer counts as lapsed?
There is no universal answer. It depends on how often your customers normally reorder. Start from your own order gaps.
Is a win-back campaign the same as retargeting?
No. Retargeting is ads to people who visited your site or app. A win-back usually goes to past customers by email or messaging.
Can I email every past customer?
That depends on how you collected the address and on your market's rules. Your lawyer decides.
Sources
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