Start a plan checkout or change the current plan

posthttps://api.expiryedge.com/v1/createSubscription

admin60/minAny method

Request

curl -X POST 'https://api.expiryedge.com/v1/createSubscription' \
  -H "Authorization: Bearer $EXPIRYEDGE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "subscription_plan_id": "prod_SJbWzGAm137eGN",
  "frequency": "Year",
  "price": 348,
  "withdrawal_consent": true,
  "withdrawal_consent_at": "2026-09-27T14:05:00.000Z"
}'

Response

{
  "status": "success",
  "type": "upgrade",
  "subscription_id": "sub_1QfT8sLm2Northwind",
  "message": "Your plan has been updated. The prorated difference has been charged to your card on file."
}

With no active plan subscription, creates a Stripe Checkout session (201) - redirect to url. With an active/trialing/past_due subscription, swaps the price in place with an immediate prorated charge (200). Referral, promo and early-bird discounts are applied server-side from the organization's state.

Body parameters

application/json

subscription_plan_idstringrequired
Stripe product id of a self-serve plan. Unknown products are rejected.
frequencystring
Month or Year (Yearly/Annual also accepted). Default Month.
Default Month
pricenumber
Amount the client displayed, in USD. Must match a server-side price for the plan and interval, otherwise 400 INVALID_PRICE.
apply_referral_discountboolean
When price is sent, apply the org referral discount on top of it.
subscription_periodinteger
Metadata only.
billing_cyclesinteger
Metadata only.
period_unitstring
Metadata only (max 20 chars).
customer_emailstring
Used only when the token carries no email.
format: email
withdrawal_consentboolean
EU withdrawal-right consent, recorded on the Stripe session.
withdrawal_consent_atstring | null
format: date-time
user_idstringDeprecated
Ignored; the caller is always the purchaser.
currencystringDeprecated
Ignored; plans are always charged in USD.

Returns

200

Existing subscription changed in place; the prorated difference was charged.

statusstringrequired
Allowedsuccess
typestringrequired
Allowedupgrade
subscription_idstringrequired
messagestring

Errors

`201`	Stripe Checkout session created.
`400`	Unknown plan, price mismatch, or another failure (`code: SUBSCRIPTION_ERROR`).
`401`	Missing, expired or invalid bearer token.
`403`	Authenticated, but your role or organization does not allow this action.
`429`	Too many requests for this endpoint from your IP. Wait `Retry-After` seconds.
`500`	Existing subscription is in an inconsistent state.