Unauthorised overdraft

The account provider may tolerate you overdrawing your account. There are two possibilities here. The first is that you overdraw your account without any arranged overdraft facility. The second is that the account provider has already granted you an overdraft facility but you exceed the contractually agreed overdraft limit.

If the account provider nevertheless executes the transaction, it is charged to your account. Account providers generally charge interest in such cases.

They may also refuse to execute the transaction.