Can You File a Tax Return Amended From Joint to Separate?

It's a taxpayer's prerogative to change her mind – sometimes. The Internal Revenue Service allows you the option of an income tax amendment or correction, but it sets a deadline for any changes you want to make. Amending tax return to change filing status can be the best way to correct your income, deductions, exemptions and credits, as well as your filing status, with an important exception if you originally filed as "married, joint."

You can use the 1040X to make an income tax amendment from married, filing separately to married, filing joint. This would allow you to claim several tax breaks that only joint filers can claim, including a lower tax rate on the total taxable income. You can also refile a tax return with a different filing status before the deadline of April 15. However, once you file a married, joint return, you can't amend the return to change your filing status to married, separate.

If you're married, you may file either joint or separate returns. Important differences exist: With a joint return, both spouses are responsible for the total tax; a separate return allows one spouse to be solely responsible for his own tax liability. But separate returns don't allow some important deductions and credits, such as the child tax credit. Married, separate returns incur a higher tax rate and usually result in a higher tax liability overall than if the couple had filed a joint return.

When you file your taxes in 2019, you'll notice several changes that may affect your decision to file jointly or separately. One is the change in tax brackets, which could change how much you pay in, especially if one of you makes more than the other. If you have children, you'll also notice you won't qualify for important credits, such as the Child Tax Credit, which doubles in 2018. However, there are income qualifications, so it's important to know the limits that vary if you choose to file separately as opposed to jointly, so it's important to pay close attention to the tax laws before you file. If you do make an error, however, amending tax return to change filing status is always a future option.

Since 2017 tax laws were less generous with tax credits and income limits, you may find that the way you filed last year was the best option. Still, if you find that amending tax return to change filing status is the best option, it isn't too late. The IRS deadline on amending mfs to mfj on Form 1040X is three years from the original due date, including extensions. If you filed on April 15, the 1040X for the year must be filed by April 15 of the third year after that date. If your extension changed your due date to Oct. 15 – which is the maximum extension allowed – your amended deadline is Oct. 15 of the third year. If you filed before Oct. 15, the date on which you filed sets the three-year clock ticking.