diff --git a/services/web/app/src/Features/Subscription/Errors.js b/services/web/app/src/Features/Subscription/Errors.js
index 2e93604137..8d4498290a 100644
--- a/services/web/app/src/Features/Subscription/Errors.js
+++ b/services/web/app/src/Features/Subscription/Errors.js
@@ -32,6 +32,12 @@ class HasNoAdditionalLicenseWhenManuallyCollectedError extends OError {}
 
 class InvalidTaxIdError extends OError {}
 
+class StripeClientIdempotencyKeyInUseError extends OError {
+  constructor() {
+    super('Stripe idempotency key was already in use')
+  }
+}
+
 /**
  * @typedef {Object} PaymentActionRequiredInfo
  * @property {string} PaymentActionRequiredInfo.clientSecret
@@ -75,4 +81,5 @@ module.exports = {
   HasPastDueInvoiceError,
   HasNoAdditionalLicenseWhenManuallyCollectedError,
   InvalidTaxIdError,
+  StripeClientIdempotencyKeyInUseError,
 }