10 Common Tax Filing Mistakes You Can Easily Avoid in 2020

Some of the simplest, most easily avoidable mistakes can delay your refund

You’re done. It took you hours, and your dog was looking for a safe place to hide, but you finished your tax return. Off it goes to the IRS. Then a notice turns up in your mailbox a few weeks later, telling you that you did something wrong.

Take heart. A mistake won’t result in a full-fledged audit in most cases, although it can hold up your refund until things get straightened out. That notice can signal trouble, however, if you got too greedy with your tax deductions or tax credits.

As unpleasant as preparing your tax return can be, you’re invariably better off taking the time to avoid mistakes. Check your return against this list of common errors before you send it off.

Keep Up With the News

Keeping on top of changes to tax law is particularly important in 2019, when you're preparing your 2018 tax return.

Here's a little test: Which tax return are you going to file? Form 1040, 1040A, or 1040EZ? You won't get very far if you selected Form 1040A or 1040EZ because they're now obsolete. Of course, you knew that if you've watched the news and followed tax blogs and articles online. The IRS has issued a whole new, revised Form 1040 for the 2018 tax year and every taxpayer must use it

Which form to use won't be a problem if you use tax preparation software—all the software providers are well aware of this new wrinkle and they're adapted their programs accordingly. They're also up to date on the many, many new provisions introduced to the tax code in 2018 subsequent to the passage of the Tax Cuts and Jobs Act (TCJA).

But if you're planning to do your taxes on your own, start by reading up first on all the changes. Make sure you have a handle on them and understand what they mean, even if you have to at least consult with tax professional for clarification. 

Know Your Filing Status

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You’re faced with choosing your filing status right off the bat when you begin preparing your tax return, and there are some intricate differences between them. The rules for qualifying can make all the difference between being able to file as head of household, a particularly advantageous filing status, or having more of your income taxed as a single taxpayer.

You must have a dependent to qualify as head of household, and you must pay for more than 50% of your household’s expenses. You can’t be married—or, at least, you can’t have lived with your spouse at any point during the last six months of the year.

Read up on the ​​rules for dependents and filing statuses before you make a selection and check off this box. If you have a child, you might be safe, but you could run into problems if you try to convince the IRS that your girlfriend is your dependent. 

Get the Data Right

How to File Form 941 for Payroll Taxes
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Math errors are the most frequent problem with tax returns, but sometimes data is erroneously entered even before you begin subtracting, adding, and dividing. 

Use the exact numbers that appear on your W-2, 1099, or other tax forms. Don’t round them up or down. The IRS will compare your tax return to the copies it receives of these forms, and a red flag will begin waving even if you claim $41,650 in income rather than $41,652. Take care not to transpose numbers, because problems will also arise if you enter $41,562 instead.

Make sure you get Social Security numbers right as well—yours, your spouse’s if you’re married, and those of your dependents. It will bog down processing of your return if what you enter doesn’t match Social Security Administration records. This includes using the exact name that appears on each individual’s Social Security card as well. And don’t make the mistake of thinking you don’t have to enter a Social Security number for your infant. You can’t claim her as a dependent without one.

So You're Getting a Refund...Or Are You?

While we're on the subject of numbers, don't forget to check...and double check...and triple check...your bank account information if you're asking the IRS to direct deposit your refund.

In most cases, you'll enter your bank information at the bottom of Form 1040. However, if you want to direct your refund into up to three accounts, this involves filing IRS Form 8888 with your tax return. It's really a very simple form, but this just gives you three opportunities to get the numbers wrong, and a surprising number of people do just that.

You have to enter your banks' routing numbers and your account numbers on the form. Consider reading them aloud to your spouse or a trusted friend after you've entered them on the form to make sure they're exactly right—he can confirm them against what's printed on your checks or account statements.

What if you make a mistake anyway? You could lose your refund. Yes, you read that right. The best-case scenario is that your bank doesn't have an account with the erroneous number you entered, so it will just send your money back to the IRS. It might mean a big delay, but eventually you'll get your money.

Otherwise, if your refund is deposited into someone else's account, you'll find yourself depending on a stranger's honesty. She might take the money and run with it rather than notify the banking institution that there's been a mistake...and the IRS will not issue you a new refund when this happens. 

About That Extra Income You Earned...

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Virtually all your income is taxable, every dime. It doesn’t matter if you didn’t receive a W-2 or 1099 form for the money—you have to report it regardless. This can come as a surprise to some taxpayers who picked up a little extra cash over the year in addition to pay from their regular jobs. Yes, you have to report it, even if someone just gave you $50 in cash or a $75 bottle of wine for fixing his glitchy computer. 

Most companies will issue you a 1099-MISC form if they pay you $600 or more as an independent contractor or freelancer, but don’t rely on this. Keep good records so you know exactly how much to claim come April’s tax deadline. And again, even if someone paid you less than $600, you still have to report the income

If you receive any type of 1099 form, know that the information it includes must go on your return somewhere. Ask a tax professional if you’re not sure where to enter it.

The issue can be particularly confusing with investment income, and it's a classic mistake with returns. Don’t set the form aside and risk forgetting about it because you’re unsure what to do with it. The IRS receives copies of these forms, too.

To Itemize or Not to Itemize

Tax Time
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Claiming deductions and/or tax credits is an area that just begs taxpayers to make mistakes. Eligibility for certain credits can be quite complicated, and multiple rules apply to many tax deductions as well.

You must itemize to claim some deductions, and itemizing means not claiming the standard deduction for your filing status. This can actually result in paying the IRS more. Yes, it might be nice to claim a deduction for that donation you made to the American Red Cross, but if your total itemized deductions add up to $5,000 and you’re eligible for a $12,000 standard deduction as a single taxpayer when you file your 2018 return in 2019, you’ll end up paying taxes on $7,000 more in income—the difference between all your itemized deductions and the standard deduction you're entitled to claim instead. 

Even if the math works out in your favor, you’ll need specific proof of the deductions you claim, particularly charitable contributions. Take time to research the rules for this or ask a tax professional. 

Calculating Eligibility for Tax Credits

Tax day
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As great as tax deductions can be, tax credits are even better. Deductions come off your income. Tax credits subtract from your tax liability, what you’ve realized you owe the IRS when you get to the last line of your tax return. 

Let’s say you owe the IRS $5,000 but you qualify for a $1,500 tax credit. Now you only owe the IRS $3,500 because the credit is deducted directly from what you owe. Or maybe you only owe the IRS $1,000 but you’re eligible for a $1,500 tax credit. If the credit is refundable, the IRS will send you a refund for the $500 balance, although if it will keep the difference if the credit is non-refundable.

Two notable tax credits are refundable: the earned income credit and the child tax credit.

The IRS doesn’t want to send you a tax credit refund without first making very sure that you meet all the rules for qualifying. In fact, one of the provisions included in the Protecting Americans from Tax Hikes (PATH) Act of 2015 requires that the IRS take a little extra time to review all claims for these refundable credits to make sure the taxpayers really are eligible.

But calculations for qualifying and how much of a credit you can claim can be complex. It’s easy to make a mistake, and it can be tempting to fudge just a little if you’re borderline because the reward is significant. Don't fudge. Take advantage of the calculators provided by the IRS to make sure you qualify and, if so, for how much. 

Many credits also typically require that you complete extra tax forms and attach them to your tax return in a certain order. If you have any doubt at all that you’re making the calculations correctly or that you’re correctly attaching what must be attached, seek help from a tax professional.

An Easy Fix

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According to the IRS, you’re 20 times more likely to goof on your tax return if you try to do it on paper. Who needs that pressure? Increase your odds of filing a trouble-free return by using tax software or IRS e-file.

These programs walk you through tax preparation by asking you questions and applying your answers to determine what credits and deductions you qualify for. They’ll tell you if you’re better off itemizing or claiming the standard deduction. Best of all, these programs do the math for you, and some even guarantee that they'll pay any financial penalties on your behalf if they make a mistake. 

Don't Be Late

Maybe you're a procrastinator by nature. Maybe you just hate preparing your taxes so much that you put it off...and off...and off. Next thing you know, it's April 1, April 10, or even April 15, and you haven't even started your return yet. 

Breathe. You're not in trouble, at least not if you file Form 4868 by April 15. The form gives you an extra six months, until Oct. 15, to file your return. But there's a catch.

You're supposed to remit any tax you might owe at the time you submit the extension request. Yes, this can be a shot in the dark if you haven't yet completed your tax return, but you'll find estimating calculators all over the internet to help you along. 

The important thing is that you send in some payment. If it ends up that you owe more—or if you make no payment at all—you'll probably be hit with interest and penalties on the outstanding amount after April 15. And if you estimate too much? The IRS will send you a refund. 

Did You Sign on the Dotted Line?

This isn't so much a problem with e-filed returns, but it's surprisingly common with old-fashioned, pen-and-paper tax returns. Taxpayers forget to sign on the dotted line. 

Keep in mind that you don't just have to sign your Form 1040. If you ended up having to submit other schedules and forms with your return, most of these have to be signed, too. You won't be audited if you forget—at least not if this is the only problem with your return—but the IRS won't process your return, either. You'll get one of those heart-stopping envelopes in the mail with an IRS return address. 

It's a simple fix, but check all your signature lines to spare yourself the aggravation. And make sure you date your return, too. 

Sometimes It Pays to Pay a Professional

Consider enlisting the help of a professional to complete your tax return if your financial situation is particularly complex. Your chances of making a mistake will drop exponentially.