Withholding Adjustments

Perhaps the most commonly overlooked error for newlyweds involves forgetting to update your W-4 to your correct name and address (at work),  and adjust your withholding amounts for your new combined household income.

“Adjust your payroll withholding as soon as you finish your honeymoon and are back at work,” says says Kay Bell, Tax Editor at Bankrate.com and Blogger at Don’t Mess with Taxes. “That applies to both newlyweds. If both of you don’t tweak how much is taken out of each of your paychecks now that you’re married, you could end up owing the Internal Revenue Service a lot at tax filing time. The IRS says that in most cases, a couple’s combined withholding is most accurate when the spouse making the most money claims all the allowances and the other claims zero allowances.”

To accurately determine the correct allowance amounts, use a Withholding Calculator based on your updated earnings and information.

Prohibited Deductions and Credits

Depending on how much money you and your spouse make in combined income, you might be excluded from certain tax credits and deductions.

For high-income earners, there is a phase-out period where some deductions and credits are limited and others are completely prohibited.

On top of that, if you choose to file separate returns (married filing separate), some of the regular credits and deductions are not allowed.

Name and Address Changes

Failure to update name changes with the Social Security Administration will cause delays in processing your tax return.

You’ll want to keep both the Social Security Administration (Form SS-5) and the IRS up to speed on your new information. Also, if you and your spouse move to a new location, you’ll need to inform the IRS (Form 8822) of your new address.

It’s imperative to keep both parties up-to-date on your name and address changes to avoid errors and possible rejections.

Marriage Penalties and Bonuses

Many couples who make equal or comparable incomes and choose to file their taxes jointly will be bumped into a higher tax bracket — getting hit with a marriage penalty.

“If you think submitting a married filing separately return will solve the problem, think again,” says Bell. “In most cases it’s more tax advantageous for married couples to file one joint return.”

All hope is not lost, however: If you and your spouse have widely differing levels of income, you could actually be eligible to earn a bonus tax credit, according Bell.

Outstanding Tax Debt or Liens

If one of you owes past-due child support, has a tax liability from a previous marriage or has a past-due student loan (none of which are wiped during bankruptcy), you should know these are outstanding tax debt or liens owed to the IRS .

Eric J. Nisall, Tax Expert at DollarVersity advises the following:

A) Adjust the W-4 withholding so there is no refund to be garnished. With no overpayment at the end of the year, the one spouse, in essence, wouldn’t be paying for the debt of the other.

B) File as “married filing separate.” While there are some deductions and credits that cannot be taken filing with status, it keeps each spouse’s tax responsibilities separate.

C) File an Injured Spouse Allocation (IRS Form 8379). This involves answering a series of questions to determine eligibility, and can help the spouse without debt avoid paying for the debt of the other.