Credits is the way to pre-pay for usage in Polar. It allows you to give your customers the ability to pre-pay for usage instead of risk getting a hefty bill at the end of the month.

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How Credits Work

When you ingest events into a Usage Meter, customers will be charged for the usage based on the product’s pricing model. However, sometimes you may want to give your customers the ability to pre-pay for usage instead of risk getting a hefty bill at the end of the month. When you issue Credits to a customer, we first deduct the Credits from their Usage Meter balance. If the Usage Meter balance reaches 0, the customer will be charged for the overage.

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Credits-only spending

To avoid any overage charges, don’t create any Metered price on your product. This way, billing won’t be triggered at all for the meter

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Issuing Credits with the Credits Benefit

The Credits benefit will credit a customer’s Usage Meter balance at different points in time depending on the type of product the benefit is attached to.

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Subscription Products

The customer will be credited the amount of units specified in the benefit at the beginning of every subscription cycle period — monthly or yearly.

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One-Time Products

The customer will be credited the amount of units specified in the benefit once at the time of purchase.

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Tracking customer’s balance

In your application, you’ll likely need to track the customer’s balance for a given meter. The easiest way to do this is to use the Customer State, which will give you the overview of the customer, including the balance for each of their active meters. You can also specifically query the meters balance using the Customer Meters API.
Polar doesn’t block usage if the customer exceeds their balance. You’re responsible for implementing the logic you need to prevent usage if they exceed it.