Are Roth IRA Income Limits Pre-Tax or Post-Tax?

Roth IRA income limits are based on neither pre-tax nor post-tax income. The IRS uses a middle figure called Modified Adjusted Gross Income, or MAGI, which starts with your adjusted gross income and adds back a short list of specific deductions and exclusions. For 2026, a single filer can make a full Roth contribution with a MAGI below $153,000, and a married couple filing jointly has a full-contribution ceiling of $242,000.¹ Getting the calculation right is the difference between contributing confidently and triggering an excise tax.

Where MAGI Sits Between Gross and Taxable Income

Your gross income is every dollar you earn before anything is subtracted. Your taxable income is the final number after all deductions come out. MAGI sits in between. It begins with your Adjusted Gross Income, the figure on line 11 of Form 1040, and then adds back specific tax breaks the IRS does not want you using to slip under the Roth income ceiling.² The rule is set in the Internal Revenue Code, which defines Roth eligibility through an AGI formula that disregards several common exclusions.³

The result is a standardized figure that reflects your actual economic resources more accurately than either gross pay or take-home pay. Someone earning $160,000 who claims a traditional IRA deduction still has to add that deduction back when checking Roth eligibility. The design prevents high earners from stacking deductions to qualify for a Roth when their real income exceeds the limits.

How to Calculate Your MAGI

The IRS publishes a worksheet in Publication 590-A that walks through the Roth IRA MAGI calculation step by step. It starts with AGI from Form 1040 line 11, subtracts income from Roth conversions, and then requires you to add back six specific items.⁴ Those add-backs are what make MAGI different from plain AGI:

Any traditional IRA deduction you claimed.
The student loan interest deduction claimed on Schedule 1.
Income excluded under the foreign earned income exclusion.
The foreign housing exclusion or deduction.
Series EE or I savings bond interest excluded on Form 8815 for education.
Employer-provided adoption benefits received tax-free.

These add-backs trace to the statute governing IRA deductions, which instructs the IRS to calculate adjusted gross income “without regard to” the sections covering student loan interest, savings bond exclusions, adoption benefit exclusions, and foreign earned income.⁵ Most people will not need to worry about all six. If you are a W-2 employee working domestically with no traditional IRA deduction, your MAGI and AGI are usually the same number. The add-backs only matter if you actually claimed one of those specific tax breaks.

Deductions That Do and Don’t Affect Your MAGI

This is where many savers get confused, and it can save you real money. Not every deduction or exclusion gets added back. The list above is exhaustive. Anything not on it stays subtracted.

The most important example: traditional 401(k) contributions reduce your MAGI for Roth IRA purposes. When you contribute to a traditional 401(k), that money never appears as taxable wages on your W-2. It is excluded from your gross income before AGI is calculated, and the Roth MAGI rules do not add it back. So if your salary is $160,000 and you defer $23,500 into a traditional 401(k) in 2026, your AGI drops to roughly $136,500 before other adjustments, which can keep you well under the Roth limit.¹

Health savings account contributions made through payroll work the same way. They reduce your W-2 income and therefore your AGI, and they are not added back for Roth MAGI. The standard deduction and itemized deductions (mortgage interest, state taxes, charitable contributions) work differently. They reduce your taxable income but not your AGI, so they have zero effect on Roth eligibility. One deduction that once appeared on the add-back list, the tuition and fees deduction, expired after 2020 and is no longer relevant.⁶

2026 Roth IRA Income Thresholds

The IRS adjusts these limits annually for inflation. For the 2026 tax year:¹

Single or head of household: full contribution below $153,000 MAGI; reduced between $153,000 and $168,000; none at $168,000 or above.
Married filing jointly: full contribution below $242,000; reduced between $242,000 and $252,000; none at $252,000 or above.
Married filing separately, if you lived with your spouse during the year: reduced between $0 and $10,000; none at $10,000 or above. This range is not adjusted for inflation.

The maximum contribution in 2026 is $7,500 if you are under 50, or $8,600 if you are 50 or older, which includes the $1,100 catch-up.¹ You have until April 15, 2027 to make a 2026 contribution, so the decision does not have to be finalized by December 31.

How the Phase-Out Range Reduces Your Contribution

If your MAGI lands inside the phase-out window, you are not shut out. You just cannot contribute the full amount. Publication 590-A gives a proportional formula.⁴

Take a single filer in 2026 with a MAGI of $158,000. Subtract the lower threshold of $153,000, which leaves $5,000. Divide by the width of the phase-out window, $15,000 for single filers, and you get 0.333. Multiply that by the full contribution limit of $7,500, giving $2,500. Subtract that from $7,500, and the reduced limit is $5,000. For joint filers, the window is $10,000 wide instead of $15,000, so the reduction happens faster as income climbs.

The IRS rounds the result up to the nearest $10, and if the reduced limit falls below $200, you can still contribute $200. Getting the math wrong is one of the most common ways people accidentally over-contribute. The worksheet in Publication 590-A walks through it line by line.

What Happens If You Contribute Too Much

If you contribute more than your MAGI allows, whether because income came in higher than expected or the phase-out math was off, the IRS imposes a 6% excise tax on the excess for every year it stays in the account.⁷ That penalty compounds annually until you fix it.

To avoid the tax, withdraw the excess and any earnings it generated by the due date of your return, including extensions.⁸ For a 2026 contribution, that is April 15, 2027, or October 15, 2027 with an extension. The earnings pulled out are taxable as ordinary income, and if you are under 59½, an additional 10% early withdrawal penalty may apply to those earnings. Contact your IRA custodian as soon as you spot the mistake; they handle the corrective distribution and calculate the net income attributable to the excess.

1
Internal Revenue Service. 401(k) Limit Increases to $24,500 for 2026, IRA Limit Increases to $7,500
2
Internal Revenue Service. Adjusted Gross Income
3
Office of the Law Revision Counsel. 26 USC 408A – Roth IRAs
4
Internal Revenue Service. Publication 590-A, Contributions to Individual Retirement Accounts (IRAs)
5
Office of the Law Revision Counsel. 26 USC 219 – Retirement Savings
6
Internal Revenue Service. About Form 8917, Tuition and Fees Deduction
7
Office of the Law Revision Counsel. 26 USC 4973 – Tax on Excess Contributions to Certain Tax-Favored Accounts
8
Internal Revenue Service. IRA Year-End Reminders