# Billing & invoices

Backed by `billing.py` (~1,315 lines), against `saas.invoice`.

## `GET /api/billing`

Tenant billing summary — current plan cost, next renewal date, payment
method on file.

## `GET /api/invoices`

List invoices for the caller's tenant.

## `GET /api/invoices/<id>`

Single invoice detail.

## `GET /api/invoices/<id>/download`

Returns the invoice as a downloadable file (PDF).

All four routes require auth and are tenant-scoped the same way instances
and backups are — an invoice belonging to another tenant returns `404`
rather than `403`, to avoid confirming the invoice ID exists at all.

For how invoices get created in the first place, see
[M-Pesa integration](../../integrations/mpesa.md) — successful STK Push
callbacks create an `account.payment` that reconciles against the tenant's
subscription invoice.