About 1 in 48 of your customers' cards expires every month

Cards usually last three to five years. Call it four: about 1 in 48 of the cards on file expires in any given month.

With 240 subscribers, that is five cards a month. At $49/mo, five failed renewals is $245 of monthly revenue at risk, or $2,940 a year if none of them come back.

Stripe's automatic card updates refresh many expired cards through the card networks, and Stripe can email customers before a card expires if you turn that on in your Billing settings. Neither catches everything. The ones they miss show up as a failed payment on renewal day, weeks after you could have asked for a new card.

Worth checking this week: which subscriptions renew after their card expires. A missed renewal also shows up as a smaller payout, one reason in why a Stripe payout does not match your sales.