# Subscriptions and Strong Customer Authentication (SCA)

For [businesses subject to Strong Customer Authentication (SCA)](/questions/businesses-affected-by-strong-customer-authentication-sca-regulations), not every transaction will require the customer to authenticate their payment. Some types of payments qualify for an [exemption](/questions/transaction-exemptions-for-strong-customer-authentication-sca), though it is important to note that exemptions are not guaranteed. The cardholders’ banks dictate whether an exemption is accepted or not.
### Existing Subscriptions
Existing subscriptions and saved card information will be grandfathered: information saved to Stripe prior to the [enforcement date for SCA](/questions/strong-customer-authentication-sca-enforcement-date) will not require additional authorization.
Collected payment methods—either as a `token`, `source` or `payment_method`—saved prior to the SCA enforcement date can be used for off-session payments without requiring additional authentication.
### New Subscriptions
Subscriptions and stored card information created after the [enforcement date](/questions/strong-customer-authentication-sca-enforcement-date) will require authentication in compliance with SCA regulation.
## Additional Information
* Visit our documentation detailing how to build an [SCA-compliant Billing integration](https://stripe.com/docs/billing/migration/strong-customer-authentication)
* Use Stripe Radar to trigger 3D Secure for payments made through Stripe Billing
* [Strong Customer Authentication (SCA) Exemptions for Recurring Charges with Stripe Billing](/questions/strong-customer-authentication-sca-exemptions-for-recurring-charges-with-stripe-billing)
* [Migrating to Stripe Billing’s Strong Customer Authentication (SCA)-Compliant Flow](/questions/migrating-to-stripe-billing-s-strong-customer-authentication-sca-compliant-flow)