You already know that you’re supposed to save money when you make purchases and you’re supposed to vehemently oppose any fees that financial institutions try to put on your account. If they want to charge you for talking to a customer service representative, you speak with a manager and get the fee waived. If they want to charge you a late fee when you have proof that the payment was sent on time, you point out the error and you get the fee reversed.

What happens when you are the one who made the mistake? Should you still aggressively pursue a refund and stop at no costs to save money, or should you accept your mistake and chalk it up to a lesson learned? A $30 late fee can really hurt – that’s a whole outfit at some secondhand stores, after all – but even if you’re totally at fault you might still be able to talk someone into refunding the fee. You may have to be pushy and even a little whiny, but when it comes to saving some money you may be tempted to do whatever you need to do to keep money in your wallet.

More: How to Avoid Bank Fees →