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

# Monthly Subscription Billing

> Monthly subscription billing flow, grace period behavior, and failure handling.

Monthly subscription radars are billed at creation, then every 30 days while active.

## Billing Mechanics

* Charge happens at radar creation.
* The next renewal timestamp is returned as `next_charge_at`.
* Renewal runs every 30 days while the radar remains active.

## Deactivation Behavior

* User-triggered deactivation keeps the radar running until the current billing cycle ends.
* After the cycle ends, the radar transitions to `inactive`.
* At cycle end, the radar transitions to `inactive`.

## Failure and Refund Behavior

* If setup fails during initial creation, a `radar_failure` webhook is sent.
* For monthly subscription, setup failures can include a refund (`refund_amount_usd > 0`).
* If renewal fails due to insufficient funds, the radar is deactivated and no refund is applied for prior usage.

## What to Monitor

* `next_charge_at` for upcoming renewal windows.
* `radar_failure` with `code: 402` for renewal failures.
* `radar_status` in API responses (`active` or `inactive`) for operational state.