There is a free 60-day trial period on the standard plan, after that period Recharge bills on a monthly basis.

If you are on the Recharge Checkout on BigCommerce or BigCommerce Checkout Integration, Recharge bills you using the credit card on file through your Store settings (click Settings and select Store).

Merchants on the Shopify Checkout Integration (including those that have migrated to the Shopify Checkout Integration) are billed on their Shopify invoice using the payment method on file with Shopify. For more information about subscription app fees and app usage fees, review Shopify's guides App charges for subscriptions and App usage charges.

There is no contract required to use Recharge on the Standard plan. Payments are month-to-month and you can cancel anytime. Merchants on the Pro plan are committed to a 12-month contract, which cannot be cancelled during this period.  Merchants on the Custom plan do sign a contract as part of the negotiation process.