What is the Stripe subscription verification charge?

If your form uses Stripe subscriptions and there is no immediate charge on the form separately, then a user may see this message:

"A small verification charge may appear on your credit card statement,
you will not be charged this value."

This is due to an update to the recommended way of integrating with Stripe. The recommended way uses a new API (called PaymentIntents) that automatically handles credit card checks like 3D Secure, and will enable us to add support for other payment sources more easily in the future.

One side-effect however, is that this new API requires there to be an immediate charge to function correctly. To handle this, we authorize a charge for $1 on the credit card, and then once the subscription has been handled, we cancel that authorization. In effect, the customer isn't charged at all, the $1 never leaves their account, however, they may temporarily see a line item for this charge in their online banking.