You don’t want to get Uncle Sam ticked off! But plenty of people make mistakes on their tax returns. Even something as ridiculous as not signing one form can delay your refund – or even result in a penalty, if you owe money! So, here are the mistakes to avoid, straight from the I-R-S:

  • Not sending in the right forms. If you file incomplete paperwork, the I-R-S sends your taxes back to you to re-do and charges you a hefty penalty.

  • Write your name on all tax forms exactly as it appears on your Social Security card. In fact, the I-R-S won’t accept your taxes if you sign with, say, your middle initial, but your Social Security card states your full middle name.

  • Choosing the wrong filing status. 67,000 taxpayers made that mistake last year! People are most often confused by the head-of-household status, which has three main requirements: You must be unmarried on the last day of the year. You must have paid more than half the costs of keeping up a home for the year. And you must have lived with a dependent person for more than half of the year, like your kids or an elderly relative. Why is “head of household” status such a big deal? Because the tax rate is usually lower than the rate for someone who files as a “single” person.

  • Double check your math! Even if you’re a math whiz, it’s always a god idea. Last year, the I-R-S caught more than 6 million math errors on tax returns.

  • File by tax day – that’s April 15th – which is a Monday this year! This is the most important one. Experts say a lot of people miss the deadline because they’re waiting on paperwork. But the I-R-S charges massive penalties and could even charge you with tax evasion if you don’t file on time, or file an extension.