> ## Documentation Index
> Fetch the complete documentation index at: https://docs.upstackdata.com/llms.txt
> Use this file to discover all available pages before exploring further.

# subscription_downgraded Event

> Track when a customer downgrades to a lower-tier plan.

Fires when a customer downgrades to a lower-tier plan. Use this event to identify at-risk accounts and measure contraction.

## JavaScript

```javascript theme={null}
window._upstack('track', 'subscription_downgraded', {
  subscriptionId: 'sub_def456',
  accountId: 'acct_abc123',
  planId: 'plan_starter_monthly',
  planName: 'Starter',
  previousPlanId: 'plan_pro_monthly',
  mrr: 4900,
  mrrDelta: -5000
});
```

## Properties

| Property       | Type   | Required | Description                      |
| -------------- | ------ | -------- | -------------------------------- |
| subscriptionId | string | Yes      | Subscription identifier          |
| accountId      | string | Yes      | Account identifier               |
| planId         | string | No       | New plan identifier              |
| planName       | string | No       | New plan name                    |
| previousPlanId | string | No       | Previous plan identifier         |
| mrr            | number | No       | New MRR after downgrade in cents |
| mrrDelta       | number | No       | MRR decrease in cents (negative) |

## When to Fire

* When plan changes from higher to lower tier
* When features are removed from subscription
* When scheduled downgrade takes effect at period end

## Stripe Webhook

Maps to `customer.subscription.updated` when the new price is lower than the previous price.