The Supreme Court’s decision to legalize same-sex marriages in a♚ll 50 states in 2015 was a watershed moment in American society. It had some major practical implications for same-sex couples as well, including the ability to file federal taxes using the married designation and filing status. 

Domestic partnerships and civil unions are legal relationships that are recognized on the state level but they're not marriages. They don’t qualify you to file federal taxes as a married couple. You can only use the marriage designation for tax filing if you're legally married.

The good news for most married same-sex couples is that they'll see a lower tax bill as a result of the Supreme Court’s decision. This may not be true for those on the extreme ends of the income spectrum, however. Their tax liability 澳洲幸运5开奖号码历史查询:may go up after they tie the knot.

The Basics

People in same-sex unions had to file separate 1040 forms with the 澳洲幸运5开奖号码历史查询:Internal Revenue Service (IRS) before 2013, designating each of them as single. One partner might qualify for head of household status if they had a dependent. The IRS then ruled in 2013 that same-sex couples could submit a federal joint tax return instead.

The number of couples filing returns together has increased since same-sex marriage became legal nationwide. More than 250,000 same-sex couples filed joint tax returns within two years of the IRS ruling.

Your days of filing as a single person are over if you're legally married on or before the last day of the tax year. You must file a married tax return either jointly or 澳洲幸运5开奖号码历史查询:separately. The only way you can file using the single status is if you're in a domestic partnership, a civil union, or you're separated by a decree of the court even if you're not yet legally divorced.

The Marriage Bonus

What effect does marriage have on a couple's taxes? The difference could be minimal for newlyweds who make roughly the same amount of money,

Consider a couple in which both spouses earn $40,000 per year in 澳洲幸运5开奖号码历史查询:taxable income or $80,000 in total for both of them. Here's the calculation if they filed single 澳洲幸运5开奖号码历史查询:tax returns for th👍eir 2025 income versus married fil♋ing jointly which combines their income.

A single filer earning $40,000 in 2025 wo♐uld be taxed as fo꧃llows:

• The first $11,925 is taxed at 10%: ($11,925 * .10 = $1,192.50)
• The remaining amount over $11,925 up to $40,000 is taxed at 12%: ($28,075 * .12 = $3,369)
• Tax in total: $4,561.50 ($1,192.50 + $3,369)

A married couple filing jointly and earning $80,000 in 2025 woꦬuld be taxe🌼d this way:

• The first $23,850 is taxed at 10%: ($23,850 * .10 = $2,385)
• The remaining amount over $23,850 up to $80,000 is taxed at 12%: ($56,150 * .12 = $6,738)
• Tax in total: $9,123 ($2,385 + $6,738)

They'd each pay $4,551.50 or $9,123 in total for both of them if they had filed as single taxpayers. Their taxes owed would also be $9,123 if they had filed as married filing jointly,

Couples with a bigger disparity in wages might receive a marriage bonus because they can average out their earnings. It might be enough to put the higher-income earner into a lower 澳洲幸运5开奖号码历史查询:tax bracket with the U.S. 澳洲幸运5开奖号码历史查询:progressive tax code. And our example doesn't take 澳洲幸运5开奖号码历史查询:deductions such as 澳洲幸运5开奖号码历史查询:individual retirement account (IRA) contributions or other factors into consideration that might reduce taxa♏ble income.

The Marriage Penalty

Unfortunately, 澳洲幸运5开奖号码历史查询:not everyone benefits at tax time when they say, "I do." Married status can have the opposite effect i🅠n some cases.

Two high-income earners who earn similar incomes can get bumped into a higher tax bracket because the 37% federal tax bracket for married couples filing jointly doesn't begin at twice the income as the same bracket for unmarried individuals. The 37% federal income tax rate for the 2025 tax year kicks in for income over $626,350 for singles. It applies to income over $751,600 for married couples filing jointly.

Wealthier couples could trigger the Medicare surtax that was instituted in 2013 if their total, combined income is large enough. That amounts to 0.9% on earnings over $250,000 for married couples filing jointly. 

The 澳洲幸运5开奖号码历史查询:marriage penalty doesn’t affect only the affluent, however. Newlyweds on the opposite end of the income spectrum may also be penalized by the IRS because adding both spouse’s incomes together could disqualify them from the 澳洲幸运5开奖号码历史查询:earned income credit (EIC). The EIC is a tax benefit geared toward lower-income families. The penalty tends to occur when couples make roughly the same amou🅰nt of money.

澳洲幸运5开奖号码历史查询: Source: The Tax Foundation

Figure 1. Most newlyweds, if anything, will experience a marriage bonus by filing as a m▨arried taxpayer. However, some low-income an♔d high-income couples can actually incur a marriage penalty if their incomes are similar. 

Filing Jointly

Same-sex couples can file in on💦e of two ways like other married taxpayers. They can submit a return as married filing jointly or married filing separately.

Couples typically benefit from filing a joint return because they’re able to average out their incomes. There’s the potential for a tax break if one of them makes substantially more than the other. Completing a joint Form 1040 return is usually the best way for married p꧙eople to 🎐lower their taxable income.

Couples who plan on 澳洲幸运5开奖号码历史查询:raising a child together have an extra incentive to file a joint return. It’s the only way they can claim a credit or an exclusion on expenses incurred when adopting a child. The maximum credit allowed for adoptions represents the total amount of qualified adoption expenses, which is $17,280 in 2025, up from $16,810 in 2024.

Filing jointly also allows taxpayers to claim the 澳洲幸运5开奖号码历史查询:child and dependent care tax credit although there are some exceptions for couples who are legally separated. They may be able to claim a credit of up to 35% of their qualifying expenditures depending on the couple's income. 

Other credits available include the EIC, the American Opportunity credit, and the 澳洲幸运5开奖号码历史查询:Lifetime Learning credit, The American Opportunity and Lifetime Learning credits help alleviate the cost of higher education. The Lifetime Learning Credit is phased out, however, for single taxpayers with modified adjusted gross incomes of more than $80,000 or $160,000 for joint married returns.

And don't forget the cost of filing. You only have to pay for the preparation of one tax form instead of two if you're using a tax preparer or tax software,

Filing Separately

That’s not to say there’s never a reason for same-sex spouses to file separately. Perhaps one spouse wants to deduct some hefty 澳洲幸运5开奖号码历史查询:out-of-pocket medical expenses. The IRS only allows you to deduct healthcare costs over 7.5% of your adjusted gross income. Claiming this deduction could amount to more money saved when using only one individual’s income. The threshold would be lower.

You’re responsible for your spouse’s tax liability when you file a joint return. You could be on the hook for any missed payments, under-reporting errors, or penalties even if your spouse earned all or most of the money that year.

The Bottom Line

Married same-sex couples face the same dilemma that other spouses face: Should they file their 澳洲幸运5开奖号码历史查询:1040 forms jointly or separately? A combined return offers a lower tax bill in most cases but it doesn’t hurt to run the numbers🍰 both ways before submitting your form to the IRS.

It’s also useful to note that the IRS allows you to file amended returns for up to three years after the date you filed your original return or within two years after the date you paid the tax, whichever is later. You might still be able to file an amended return and reap the financial rewards due to you if you filed in a way that wasn't to your financial advantage.