An account reserve is an amount of funds set aside in your PayPal account to help make sure that you're able to meet any liabilities you may incur from a chargeback, claim or bank reversal, where no other funds are available. The reserved amount still belongs to you but is unavailable for use (including withdrawal).

A rolling reserve is a reserve where a percentage of each transaction you receive each day is held and then released later, on a scheduled basis. For example, your reserve could be set at 10% and held for a 90-day rolling period. It means 10% of the funds you receive on day 1 is held and then released on day 91, 10% of the funds you receive on day 2 is held until day 92, etc. Rolling reserves are the most common type of reserve.

A minimum reserve is a specific minimum amount of funds that you’re required to keep available in the balance of your business PayPal account. We either take the minimum reserve as a percentage of funds held until it reaches a certain amount, or a one-time amount (this is known as an upfront reserve).