Prorate an invoice

Bill a customer for part of a period by adding a one-time percentage discount.

To bill for only part of a period, such as a customer who starts mid-month, add a one-time discount to the invoice.

Prorate a monthly invoice

1. In the invoice builder, add the product at its full price.
2. Under the subtotal, select Add Discount or Surcharge.
3. Select Create New.
4. Name the discount so your customer understands it, such as "March, prorated".
5. Set it as a percentage discount.
6. Enter the percentage that matches the unused part of the period. For example, if your customer starts halfway through the month, enter 50.
7. Save the discount and finish the invoice.

Need help? Email support@finli.com.

Updated October 22, 2026