---
agentTools:
  projectIndex: https://docs.api.rillet.com/llms.txt
---

# Invoice Dates on Contracts with Minimum Commitments

The following endpoints now reject a contract with a nonzero minimum commitment when its invoicing
`day` or `month_day` does not match the contract's `start_date`:

* `POST /contracts`
* `POST /contracts/{contract_id}/amendments`
* `POST /contracts/{contract_id}/amendments/preview`

Align the invoicing `day` or `month_day` with `start_date` when creating or amending these contracts.

This applies to contract-level minimum commitments in V1 through V4 and item-level minimum commitments
in V3 and V4. Invalid requests return HTTP 400 with error type
`custom_invoice_date_not_allowed_with_minimum_commitment`.