First came love, then came marriage, then came filing with the internal revenue service (IRS). Every couple should file jointly to get the tax benefits of being married, right? Wrong—many couples don't realize that filing separately might better their financial situations. In some instances, love doesn't have a place in your tax return.

  • Filing separately even though you are married may be better for your unique financial situation.
  • Reasons to file separately can include separation, divorce, liability issues, and deduction scales.
  • There are also many disadvantages of filing separately that couples should evaluate prior to choosing this option.

The Disadvantages of Filing Separately

There are a number of reasons why the married-filing-separately status is seldom chosen by couples. The biggest reason is the forfeiture of a number of major tax credits and deductions that are available to those who file jointly, such as:

Furthermore, when it comes to married filing separately, both spouses must choose the same method of recording deductions, even if one of them would be better off making under the opposite method.

For example, if one spouse decides to itemize deductions, then the other spouse must do so as well, even if their itemized deductions are less than the standard deduction. If one spouse has itemized deductions of $20,000 and the other has only $2,500, the second spouse must claim that $2,500 rather than the larger standard deduction. So filing separately is a good idea from a tax savings standpoint only when one spouse's deductions are large enough to make up for the second spouse's lost deduction amount.

Reasons for Couples to File Separately

There are a number of situations, however, in which it is best for a couple to file separately:

Divorce or Separation

This was the original reason for which this status was created. For a variety of reasons, divorcing or separated couples may not be willing to file their taxes jointly.

Liability issues

Filing separately also may be appropriate if one spouse suspects the other of tax evasion. In that case, the innocent spouse should file separately to avoid potential tax liability for the other spouse. This status can also be elected by one spouse if the other refuses to file a tax return at all.

Diverse pay or deduction scales

Protecting yourself from a negative outcome isn't the only reason to file separately. Today, even the most happily married couple may come out ahead by choosing this route.

The primary instance is with childless couples, in which one spouse has considerably higher income and the other spouse has substantial potential itemized deductions.

For example, consider a situation in which one spouse is a doctor earning $200,000 a year, while the other is a teacher earning $45,000. The teaching spouse has surgery during the year and pays $12,000 in unreimbursed medical expenses. The IRS rule for deducting unreimbursed medical expenses dictates that only expenses in excess of 7.5% of the filer's AGI (formerly 10% in tax years 2013 - 2016) can count as a miscellaneous itemized deduction.

  • If the couple files jointly, only expenses in excess of $18,375 ($245,000 x 7.5%) will be deductible. Therefore, none of the teacher's medical expenses could be deducted because they total less than $18,375.
  • But if the couple filed separately, the cost would easily exceed the teacher's threshold for medical deductions, which would be $3,375 ($45,000 x 7.5%), based only on the teacher's AGI. This would leave an eligible deduction of $8,625 for the teaching spouse to claim on Schedule A of the 1040.

Even if, in a normal year it would make more sense for this couple to file jointly, in the year of the expense, filing separately might make sense.

Please note the source of funds is highly important in this type of situation. According to the IRS, "if you and your spouse live in a noncommunity property state and file separate returns, each of you can include only the medical expenses each actually paid. Any medical expenses paid out of a joint checking account in which you and your spouse have the same interest are considered to have been paid equally by each of you, unless you can show otherwise." 

Bottom Line

There are many factors involved in determining whether it is better to file separately or jointly. When a couple is unsure of which filing status to choose, it makes sense to compute the tax return both ways to determine which will give the biggest refund or lowest tax bill.

In general, couples with no dependents or education expenses can benefit from filing separately if one has high income and the other has substantial deductions. Generally, other instances when this is appropriate are related to divorce, separation, or relief from liability for tax fraud or evasion. If you are unsure whether this strategy is appropriate for you, consult your tax advisor. It's always good to check whether there are any tax deductions you may be missing.