If you’re happily saying “yes” this year, know that the IRS can be a real buzzkill.

While many couples end up paying less tax after getting married, some face a ‘marriage penalty’ – meaning they end up paying more than if they had remained single and declared as taxpayers singles.

The penalty can arise when tax bracket thresholds, deductions and credits are not double the amount allowed for single filers – and this can hurt both high-income and low-income households.

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“It was more prevalent before the [2017] Tax Cuts and Jobs Act,” said Garrett Watson, senior policy analyst for the Tax Foundation. “It’s more common to have a wedding bonus than a penalty, but the details matter.”

With a record 2.5 million weddings expected this year, newlyweds — especially those earning similar sums — may want to take a hard look at the impact of their married status on their tax situation.

For marriages occurring anytime this year, spouses are required to file their 2022 tax returns (due April 2023) as a married couple, jointly or separately. (However, filing separate returns is only financially beneficial to spouses in certain situations.)

Here’s what you need to know:

A larger tax bill can come from a few different sources for high earners.

For 2022, the top federal rate of 37% kicks in at taxable income of $539,901 for single filers. However, for married couples filing jointly, this rate applies to incomes of $647,851 or more.

“All the [income] the hooks are doubled except for the very top hook,” Watson said.

For example: two people who each have an income of $500,000 would fall into the tax bracket with the second highest rate (35%), if they filed as single taxpayers.

However, as a married couple with a joint income of $1 million, they would pay 37% on $352,149 of that amount (the difference between their income and the $647,851 threshold for the higher rate).

Other parts of the tax code can also negatively affect high earners when they marry.

For example, Medicare’s regular payroll tax — 3.8%, which is split between employer and employee — applies to earnings up to $200,000 for single taxpayers. Anything over that amount is subject to an additional 0.9% Medicare tax.

For married couples, this additional tax is $250,000.

Similarly, a 3.8% investment income tax applies to single people with adjusted adjusted gross income over $200,000. Married couples must pay the tax if their income exceeds $250,000. (The tax applies to items such as interest, dividends, capital gains, and rental or royalty income.)

Additionally, the state and local tax deduction limit – also known as SALT – is not doubled for married couples. The $10,000 limit applies to single filers and married filers. (Married couples who file separately receive $5,000 each for the deduction). However, write-off is only available to detailing taxpayers.

For low-income couples, a marriage penalty may arise from the earned income tax credit.

The credit is available to taxpayers who work with children, as long as they meet income limits and other requirements. Some low-income people without children are also eligible.

However, the income limits that come with the tax relief are not doubled for married couples. (Also be aware that the extended version of the credit, in place for 2021, has not been extended for 2022.)

For example, a single taxpayer with three or more children may be entitled to a maximum of $6,935 with income up to $53,057 for 2022. For married couples, this ceiling is not much higher: 59 $187.

Depending on where you live, there may be a marriage penalty built into your state’s marginal tax brackets. For example, Maryland’s top rate of 5.75% applies to income over $250,000 for single filers, but over $300,000 for married couples.

Some states allow married couples to file the same return separately to avoid being hit with a penalty and losing credits or exemptions, according to the Tax Foundation.

In the meantime, if you are already receiving your Social Security retirement benefits, getting married may have tax implications.

For single filers, if the total of your adjusted gross income, non-taxable interest, and half of your Social Security benefits is less than $25,000, you will not owe tax on those benefits. However, for married couples filing jointly, the threshold is $32,000 instead of double the amount for individuals.

Also, if you or your new spouse contribute to traditional or Roth Individual Retirement Accounts, be careful how much you put into those IRAs. There are limits that apply to deductions and contributions, and the income of both spouses feeds into the equation.