v1

latestOpenAPI 3.1.02026-07-228956435.8 KB
Subscription items

Create a subscription item

Adds an item to an existing subscription. Fintoc creates a new price from price_data, referencing an existing product (product) or defining one inline (product_data). The new price must use a currency compatible with the subscription's existing items (a CLF price bills within a CLP subscription) and the same recurring interval. Fintoc bills the item starting from the subscription's next invoice and does not prorate the current billing period.

post/subscriptions/{subscription_id}/items

Path parameters

subscription_idstring required

The id of the subscription to add the item to.

Request body

quantityinteger required

Number of units of the price the item bills for. Must be greater than zero.

Example request

{
  "price_data": {
    "currency": "CLP",
    "recurring": {
      "interval": "month",
      "interval_count": 1
    },
    "unit_amount": 5000,
    "product": "prod_2c4mDgwQqkNwMHnXSc4DBjkbcWz",
    "product_data": {
      "name": "Extra seat",
      "description": "An additional seat for the workspace.",
      "image_url": "https://example.com/image.png",
      "metadata": {
        "category": "saas"
      }
    }
  },
  "quantity": 2
}

Response

Subscription item created. Fintoc bills it starting from the subscription's next invoice.

idstring required

Unique identifier of the subscription item.

object'subscription_item' required

Type of the object. Always subscription_item.

quantityinteger required

Number of units of the price the item bills for.

Example response

{
  "id": "si_2c4mDfkPLLrLTCJ3wPCEHGYpkVf",
  "price": {
    "currency": "CLP",
    "product": {
      "id": "prod_2c4mDgwQqkNwMHnXSc4DBjkbcWz",
      "created_at": "2026-06-01T15:00:00Z",
      "description": "Access to every premium feature.",
      "image_url": "https://example.com/image.png",
      "metadata": {
        "category": "saas"
      },
      "mode": "live",
      "name": "Premium plan"
    },
    "recurring": {
      "interval": "month",
      "interval_count": 1
    },
    "unit_amount": 10000
  },
  "quantity": 1
}