Change Subscription Rate Card

post/subscriptions/{subscription_id}/change-rate-card

Path ParametersExpand Collapse

subscription_id: string

Body ParametersExpand Collapse

checkout_callback_urls: CheckoutCallback { cancelled_url, success_url }

The URLs to redirect to after the checkout is completed or cancelled, if a checkout is required.

cancelled_url: string

The URL to redirect to after the checkout is cancelled.

minLength1

formaturi

success_url: string

The URL to redirect to after the checkout is successful.

minLength1

formaturi

rate_card_id: string

The ID of the rate card to change the subscription to.

upgrade_behavior: optional "prorate" or "rate_difference"

The behavior to use when upgrading the subscription. If 'prorate', the customer will be charged for the prorated difference. If 'rate_difference', the customer will be charged for the difference in the rate cards without respect to time.

Accepts one of the following:

"prorate"

"rate_difference"

ReturnsExpand Collapse

result: object { action, type } or object { subscription, type }

The result of the request. If the request is successful, the subscription resource will be returned. If the request is requires action, the action to take to complete the request will be returned.

Accepts one of the following:

RequiresAction = object { action, type }

action: object { checkout_url, type }

The action to take to complete the request.

checkout_url: string

The URL of the checkout page to redirect to in order to complete the request.

type: "checkout"

Accepts one of the following:

"checkout"

type: "requires_action"

Accepts one of the following:

"requires_action"

Success = object { subscription, type }

subscription: SubscriptionResource { id, cancels_at_end_of_cycle, current_period, 6 more }

The updated subscription resource.

id: string

The ID of the subscription.

cancels_at_end_of_cycle: boolean

Whether the subscription will be cancelled at the end of the current cycle.

current_period: object { end, start, inclusive_end, inclusive_start }

The current period of the subscription if it is active.

end: string

formatdate-time

start: string

formatdate-time

inclusive_end: optional boolean

inclusive_start: optional boolean

cycles_next_at: string

The date and time the next cycle of the subscription will start.

formatdate-time

effective_at: string

The date and time the subscription became effective.

formatdate-time

metadata: map[string]

rate_card_id: string

The ID of the rate card of the subscription.

status: "active" or "cancelled" or "paused"

The status of the subscription.

Accepts one of the following:

"active"

"cancelled"

"paused"

subject_id: string

The ID of the subject that the subscription is for.

type: "success"

Accepts one of the following:

"success"

Change Subscription Rate Card

curl https://api.uselark.ai/subscriptions/$SUBSCRIPTION_ID/change-rate-card \
    -H 'Content-Type: application/json' \
    -H "X-API-Key: $LARK_API_KEY" \
    -d '{
          "checkout_callback_urls": {
            "cancelled_url": "https://example.com/try-again",
            "success_url": "https://example.com/completed"
          },
          "rate_card_id": "rc_jQK2n0wutCj6bBcAIrL6o07g"
        }'

{
  "result": {
    "subscription": {
      "id": "rc_sub_PuLvkNSP3IBCvjayBD3TXNQ6",
      "cancels_at_end_of_cycle": false,
      "current_period": {
        "end": "2025-11-01T00:00:00Z",
        "start": "2025-10-01T00:00:00Z",
        "inclusive_end": false,
        "inclusive_start": true
      },
      "cycles_next_at": "2025-11-01T00:00:00Z",
      "effective_at": "2025-10-01T00:00:00Z",
      "metadata": {},
      "rate_card_id": "rc_AJWMxR81jxoRlli6p13uf3JB",
      "status": "active",
      "subject_id": "subj_VyX6Q96h5avMho8O7QWlKeXE"
    },
    "type": "success"
  }
}

Returns Examples

{
  "result": {
    "subscription": {
      "id": "rc_sub_PuLvkNSP3IBCvjayBD3TXNQ6",
      "cancels_at_end_of_cycle": false,
      "current_period": {
        "end": "2025-11-01T00:00:00Z",
        "start": "2025-10-01T00:00:00Z",
        "inclusive_end": false,
        "inclusive_start": true
      },
      "cycles_next_at": "2025-11-01T00:00:00Z",
      "effective_at": "2025-10-01T00:00:00Z",
      "metadata": {},
      "rate_card_id": "rc_AJWMxR81jxoRlli6p13uf3JB",
      "status": "active",
      "subject_id": "subj_VyX6Q96h5avMho8O7QWlKeXE"
    },
    "type": "success"
  }
}