Overage Billing

Overage billing allows you to bill based on the amount of disk or bandwidth that a customer used over the base amount for the package. You can invoice customers for usage billing either independently from the related service or as billable items on the client’s next invoice for that service.

Configure Overage Billing

To enable and configure overage billing for a product:

  1. Go to the Other tab at Configuration () > System Settings > Products/Services.
  2. Check Overages Billing.
  3. Enter the Soft Disk Limit and Soft Bandwidth Limit to include with the package.
    • To bill for all usage without an included base amount, set these to 0.
    • If you only want to charge for one of these options (disk space or bandwidth), set the other value to a very high limit (for example, 999999999).
  4. Enter the cost for disk space and bandwidth in your default currency for Disk Overages Cost and Bandwidth Overages Cost.
    • You can use up to four decimal places.
    • The system will multiply this number by the overage amount.
  5. Choose the unit of measure for overages.
  6. Click Save.
  7. Go to Configuration () > System Settings > Automation Settings.
  8. Enable Overage Billing Charges to invoice clients for their overage usage.
  9. If you want to suspend services due to unpaid overage costs, enable Include on Next Invoice.
  10. Click Save Changes.

Calculating Use

The system calculates usage charges on the last day of each month. It calculates overages to one-tenth of a gigabyte. For example, an overage of 1.5 GB at $1.00 per GB will bill $1.50.


If you chose to add the overage charge to the next invoice, the system adds it as the final line item on the invoice. If you chose to invoice independently, it will be the only item on the invoice.

Overage invoice line items use the following format:

Shared Hosting - whmcsdemo.com (01/05/2014 - 31/05/2014)
Total Disk Usage = 1.5 GB - Overage Charge = 0.5 GB @ 1.50/GB
Shared Hosting - whmcsdemo.com (01/05/2014 - 31/05/2014)
Total Bandwidth Usage = 7.5 GB - Overage Charge = 2.5 GB @ 2.50/GB

You can only calculate overage billing in your system’s default currency. WHMCS will automatically convert overage prices into a client’s currency using the rates at Configuration () > System Settings > Currencies.

Custom Fields and Configurable Options

You can override the overage billing limits for a product using Disk Space or Bandwidth custom fields or configurable options. If you do this, the system will use these values when it calculates overages. For example, if you set the soft disk limit to 10MB and set a configurable option to 20MB, you would only charge the client for an overage after they go above 20MB.

  • When setting up a configurable option for the purpose of overriding overage billing limits, the option type can be any type that returns a numerical value (Drop Down, Radio, or Quantity).
  • Friendly names can display non-numerical values to the customer. You can find the unit of measurement in the Other tab at Configuration () > System Settings > Products/Services. For example, 150|150GB or 999|999MB.

Last modified: June 14, 2024