Getting married is a major life change — and it comes with real tax consequences. Whether you end up paying more or less depends on your combined income, the gap between your earnings, and the choices you make on your return.
Your Filing Status Changes
Once you're legally married, you have two filing options:
- Married Filing Jointly (MFJ) — both spouses' income and deductions are combined on one return
- Married Filing Separately (MFS) — each spouse files their own return independently
Most couples benefit from filing jointly. Married Filing Separately has a narrower tax bracket, loses access to several credits, and limits deduction options.
The Marriage Bonus
If there's a large income gap between spouses — for example, one earns $90,000 and the other earns $20,000 — filing jointly often results in lower combined taxes than filing single. The higher earner's income is effectively shifted into lower brackets by the combination.
The Marriage Penalty
If both spouses earn similar incomes at higher levels, their combined income can push them into higher tax brackets faster than if they filed as two single taxpayers. This is the marriage penalty.
It's most pronounced when:
- Both spouses earn roughly equal amounts
- Their combined income crosses bracket thresholds
- Their combined income triggers the Net Investment Income Tax or Additional Medicare Tax
How Marriage Affects Your W-4
After getting married, update your W-4 at work. If you both work and use the old default settings, you're likely to under-withhold — especially if you don't account for the fact that your combined income may push you into a higher bracket.
Use the IRS Tax Withholding Estimator or work with a tax preparer to calculate the right withholding adjustments. A mid-year review is especially useful if you marry late in the year.
Standard Deduction Doubles
The married filing jointly standard deduction ($29,200 for 2024) is exactly double the single deduction ($14,600). This is a straightforward benefit — no penalty here.
Credits and Benefits That Change
Getting married can affect eligibility for:
- Earned Income Tax Credit — income limits apply to combined income
- Student loan interest deduction — phases out at higher income for joint filers
- IRA deductibility — if either spouse is covered by a workplace retirement plan, the deduction phases out based on combined income
- Child and Dependent Care Credit — both spouses must have earned income to qualify
Name Change and Social Security Number
If you change your name, notify the Social Security Administration before filing your tax return. The IRS matches names to SSNs — a mismatch can delay your return or trigger a notice.
The Bottom Line
Marriage creates both opportunities and complications in your tax picture. Review your withholding immediately, understand how your combined income interacts with tax brackets, and consider a tax planning session in the year you marry — especially if both spouses work or one has significant investment income.