Overage Invoices for Contracted Plans: how spend limits, premiums, VAT, and billing timing work

## Customers have a contracted spend limit Customers on contract plans have a **defined contract value**, which represents the amount of usage you have prepaid or committed to for the contract period (often annual but sometimes monthly). - This contract value acts as a **spend allowance** for checks run on the platform. - All usage is tracked against this value as you performs checks. ## Spend is monitored against the contract value Throughout the contract period: **The total spend generated by checks** is accumulated. - This spend is compared against the contract value. If you stay within the contract value → **no additional charge**. If you exceed the contract value → you enter **overage**. ## Overspend is charged at a 20% premium Zinc’s standard policy is to apply a **20% overage premium** on any spend above the contracted amount. The formula you can use is: **Overage charge = (Total Spend − Contract Value) × 1.2** This means the overspend is charged at **120%** of its normal value**. Overages are then subject to a 20% VAT charge. ## Overage invoices are typically issued monthly Operationally: - Overage invoices are usually generated between **the 3rd–10th of the month** once spend data is confirmed. - Our Finance Team prepares the invoice and Account Managers may review before it is sent.