How to Recover Abandoned Checkouts on Polar.sh

Polar.sh is an excellent way to sell digital products and subscriptions as a developer. It handles payments, tax as merchant of record, license keys, and more. But like most billing platforms, it focuses on the moment of sale, not the revenue that slips away around it. If you sell on Polar, here is what it recovers for you by default, what it does not, and how to close the gaps.

What Polar recovers on its own

Polar includes a basic dunning flow for failed subscription renewals. When a renewal charge fails, the subscription moves to past_due, Polar retries the charge on a schedule, emails the customer to update their payment method, and can hold benefits for a grace period before revoking access. For involuntary churn, that is a solid baseline.

What Polar does not do

Two of the three big recovery moments are not covered natively:

• Abandoned checkouts. When someone starts a Polar checkout and does not finish, there is no built-in “you left something behind” follow-up. The intent is captured, but nothing acts on it.
• Win-back after cancellation. When a subscriber cancels, Polar revokes access. There is no automatic sequence to bring them back later with the right message or offer.

These are exactly the moments where targeted follow-up earns money, because the person already engaged with your product once.

How to recover abandoned checkouts on Polar

The mechanics are the same whether you build it yourself or use a tool:

• Listen to Polar webhooks. Subscribe to checkout and subscription events so you know when a checkout was created but never completed within a window (Polar has no native “expired” event, so you detect this with a timed sweep).
• Filter out the noise. Cheap digital products attract card-testing bots and throwaway emails. Suppress those before you send, both because they will never convert and because emailing them hurts your sending reputation.
• Send from your own verified domain. Set up DKIM, SPF, and DMARC so recovery emails land in the inbox rather than spam. This is the single biggest factor in whether recovery works.
• Measure with a holdback. Randomly exclude a small percentage of abandons from emails as a control group, so you can prove the revenue you recovered was actually caused by your follow-up.

The three loops, together

A complete recovery setup for a Polar store covers all three events: abandoned checkout, failed renewal (improving on Polar’s default with branded, editable, measured emails), and post-cancellation win-back. They run on the same foundation, so it makes sense to treat them as one system rather than three separate projects.

Snagr is built for exactly this. It connects to Polar in one OAuth click, watches those events, sends recovery emails from your own domain, and reports the incremental revenue it recovers against a 5% holdback so you know the number is real. It is free for your first 50 recovery emails a month, with no card required to start.