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

# Age Estimation Billing

> How iDenfy bills age estimation: the finances it draws on, what the document step-up costs, and when each fee is charged.

Age Estimation is billed against **Age Estimation finances** -- allocated to your account separately from your general funds.

* Both the age-estimation fee and the document step-up fee draw on those finances. The step-up is charged as an **Age Estimation Document Scan**, so your general document scan credits are never used and it does not appear against your document scan usage.
* **Without available Age Estimation finances the feature is unavailable**, no matter how much general balance the account holds -- session creation is rejected.
* The age-estimation fee is charged once per terminal result, on both `COMPLETED` and `FAILED`. Sessions that merely expire are not charged.
* The Age Estimation Document Scan fee follows standard document verification billing: charged when the document check completes, and on failure only if your account is configured to charge all completed verifications.
* Age Estimation finances can carry their own expiration, independent of your other funds.

At session creation your Age Estimation finances are pre-checked for both applicable fees; if they can't cover the session the request is rejected -- see [error responses](/age-estimation/create-session#errors) for how this surfaces on the API.


## Related topics

- [Age Estimation Overview](/guides/dashboard/age-estimation/overview.md)
- [Age Estimation Dashboard](/guides/dashboard/age-estimation/dashboard.md)
- [Age estimation result](/api-reference/webhooks/age-estimation-result.md)
- [Age Estimation Webhooks](/age-estimation/webhooks.md)
- [Age Verification](/guides/dashboard/kyc/age-verification.md)