The marriage penalty is when getting married affects how much money you have to pay in taxes, and not in a good way. Imagine you have a big bag of candy that you're supposed to share evenly with your friend. But when you both open the bag, you realize that you'll have to pay more taxes than if you kept the candy to yourself. This is what happens when you get married and file your taxes together. The amount of money you owe in taxes goes up because your income as a couple is combined and may push you into a higher tax bracket, which means you have to pay more taxes. This may not seem fair, but it depends on many factors such as income and deductions, so it's important to talk to a grown-up who knows about taxes before making any decisions.