A Roth IRA uses posttax money, not pretax
You fund a Roth IRA with money you have already paid income tax on. This is the opposite of a traditional IRA or a 401(k), where you contribute pretax dollars and reduce your taxable income for that year. With a Roth, you get no tax deduction when you put the money in.
The trade-off is that when you withdraw the money in retirement, you pay no tax on the earnings. The growth inside the account is tax-free, and so are the withdrawals. This makes a Roth useful if you expect to be in a higher tax bracket later, or if you simply want to lock in today's tax rate and avoid surprises in retirement.
The IRS limits how much you can contribute to a Roth each year. For 2024, the limit is $7,000 if you are under 50, and $8,000 if you are 50 or older. These limits change annually. You can only contribute if your income is below a certain threshold, which also varies by year and filing status.
Key Takeaways
- Roth IRA contributions come from money you have already paid income tax on, so you receive no tax deduction in the year you contribute.
- The earnings and withdrawals in retirement are completely tax-free, which is the main advantage over pretax retirement accounts.
- You can only contribute to a Roth if your income falls below IRS limits, which change each year depending on whether you file as single or married.
- Annual contribution limits are $7,000 (under 50) or $8,000 (50 and older) for 2024, and these amounts adjust yearly for inflation.
How posttax contributions affect your taxes right now
When you put money into a Roth IRA, you do not reduce your taxable income for that year. If you earn $60,000 and contribute $7,000 to a Roth, your taxable income is still $60,000. You pay tax on the full amount.
This is different from a traditional IRA contribution, which lowers your taxable income. If you contributed $7,000 to a traditional IRA instead, your taxable income would drop to $53,000. That means a smaller tax bill in the year you contribute.
The posttax structure also means you cannot deduct Roth contributions on your tax return. You simply fund the account with after-tax dollars and move forward. This is why some people choose a Roth only after they have maxed out other pretax options, like an employer 401(k) match.
Why the tax-free growth matters in retirement
The real benefit of posttax contributions shows up decades later. Money inside a Roth grows tax-free. If you invest $7,000 and it grows to $50,000 over 30 years, you owe no tax on that $43,000 in gains.
When you withdraw money from a Roth in retirement, the entire withdrawal is tax-free — both your original contributions and all the earnings. A traditional IRA or 401(k) taxes you on the full withdrawal amount, because you never paid tax on the money going in.
This tax-free withdrawal is especially valuable if you expect your income or tax bracket to be higher in retirement, or if you simply want certainty about your tax bill. You lock in today's tax rate and avoid the risk that tax rates will rise in the future.
Income limits that determine who can contribute
The IRS sets income thresholds for Roth contributions. If your income is too high, you cannot contribute at all. These limits depend on your filing status and change each year.
For 2024, if you file as single, you can contribute the full amount if your modified adjusted gross income (MAGI) is below $146,000. The contribution phases out between $146,000 and $161,000. Above $161,000, you cannot contribute to a Roth at all.
If you are married filing jointly, the full contribution range is $230,000 to $240,000 for 2024. Married filing separately has much lower limits. These thresholds shift upward each year, usually by $1,000 to $3,000, depending on inflation.
Your MAGI is not the same as your gross income. It includes certain deductions added back, such as student loan interest and foreign earned income. If you are unsure whether you are under the limit, use the IRS worksheet or speak with a tax preparer.
Roth versus traditional: the posttax and pretax comparison
| Feature | Roth IRA | Traditional IRA |
|---|---|---|
| Contribution type | Posttax (after-tax dollars) | Pretax (reduces taxable income) |
| Tax deduction when you contribute | No | Yes (if you meet income limits) |
| Tax on earnings while invested | None | Deferred until withdrawal |
| Tax on withdrawals in retirement | None | Full amount is taxable |
| Income limits to contribute | Yes, phases out at higher income | No income limit, but deduction phases out |
| Required withdrawals in retirement | None during your lifetime | Yes, starting at age 73 |
What happens if your income is too high
If your income exceeds the Roth limit, you have a few options. One is the backdoor Roth, a legal strategy where you contribute to a traditional IRA with posttax money, then convert it to a Roth. This works regardless of income, but it has tax complications if you already have pretax IRA money.
Another option is a mega backdoor Roth through an employer 401(k) plan, if your plan allows it. This lets you contribute much larger amounts as posttax money and convert to a Roth. Not all employers offer this feature.
If neither option is available, you can simply contribute to a traditional IRA instead. You will not get a tax deduction if your income is high and you have an employer retirement plan, but the money still grows tax-deferred until retirement.
Frequently Asked Questions
Can I contribute to a Roth IRA if I have a 401(k) at work?
Yes. Having a 401(k) does not prevent you from opening or funding a Roth IRA, as long as your income is below the Roth income limits. The two accounts are separate. You can contribute to both in the same year, up to each account's individual limit.
Do I have to report Roth contributions on my tax return?
You do not need to report Roth contributions themselves on your federal tax return. However, if you do a backdoor Roth conversion, you must file Form 8606 to report it. Failing to file this form can result in the IRS taxing the conversion twice.
What if I withdraw money from my Roth before retirement?
You can withdraw your original contributions anytime, tax-free and penalty-free. Withdrawals of earnings before age 59½ are taxed as income and may face a 10% penalty, unless you may have access to for an exception like a first-time home purchase or disability.
Does a Roth conversion count as income?
Yes. When you convert a traditional IRA to a Roth, the amount converted is added to your taxable income for that year. This can push you into a higher tax bracket or affect other tax benefits. Plan conversions carefully with a tax preparer.
Can my spouse open a Roth IRA if they do not work?
Yes, if you file taxes jointly and have earned income. Your spouse can open a spousal Roth IRA and contribute up to the annual limit, as long as your combined household income is below the Roth income limits for married filing jointly.