How a Backdoor Roth Conversion Works When Your Income Is Too High

A backdoor Roth is a way to put money into a Roth IRA when your income exceeds the direct contribution limits

If your income is too high to contribute directly to a Roth IRA, a backdoor Roth conversion lets you move money from a traditional IRA into a Roth IRA instead. You contribute to a traditional IRA (which has no income limit), then convert that money to a Roth IRA. The IRS allows this move, and it accomplishes the same goal: getting money into a Roth account where it can grow tax-free.

The catch is that you pay income tax on the converted amount in the year you do the conversion. If you have other traditional IRA money already saved, the tax bill can be larger than expected. The process itself takes a few weeks and requires coordination between two accounts, but it is straightforward once you understand the steps.

Key Takeaways

A backdoor Roth works by contributing to a traditional IRA, then converting it to a Roth IRA within the same tax year.
You must pay income tax on the full converted amount, calculated at your ordinary tax rate for that year.
If you have other traditional IRA balances, the pro-rata rule means you will owe tax on a portion of those too, even if you only convert the new contribution.
The conversion itself takes two to four weeks; you should complete it before the end of the tax year to keep the process clean.
Your brokerage or IRA custodian handles the conversion paperwork — you do not file a separate application with the IRS.

When you need a backdoor Roth instead of a direct contribution

The IRS sets income limits for direct Roth contributions. For 2024, if you file as single, the limit phases out between $146,000 and $161,000 of modified adjusted gross income (MAGI). If you are married filing jointly, it phases out between $230,000 and $240,000. Once your income exceeds the upper limit, you cannot contribute directly to a Roth IRA at all.

A backdoor Roth bypasses this limit because traditional IRA contributions have no income ceiling. Anyone can contribute to a traditional IRA regardless of how much they earn. This is why the backdoor strategy exists: it is the legal workaround for high earners who want Roth accounts.

You do not need to use a backdoor Roth if your income is below the limit. A direct contribution is simpler and involves no tax bill. Only use the backdoor method if you have confirmed that your MAGI puts you over the threshold for the year you are contributing.

The step-by-step process for a backdoor Roth conversion

The conversion happens in two parts: the contribution and the conversion itself.

Step 1: Contribute to a traditional IRA. Open a traditional IRA if you do not have one, or use an existing account. Contribute the amount you want to convert — for 2024, the limit is $7,000 per person ($8,000 if you are 50 or older). You can contribute this money at any time during the tax year or even up until the tax filing deadline the following year (usually April 15).

Step 2: Wait a few business days. Let the contribution settle in the traditional IRA. This usually takes two to five business days depending on your brokerage.

Step 3: Request the conversion. Contact your IRA custodian (your bank, brokerage, or investment firm) and ask them to convert the traditional IRA balance to a Roth IRA. You can do this online, by phone, or by mail. The custodian will ask you to confirm the amount and which Roth IRA account to send it to. If you do not have a Roth IRA yet, you can open one at the same institution before requesting the conversion.

Step 4: The money moves. The custodian transfers the funds from the traditional IRA to the Roth IRA. This usually takes two to four weeks. You will receive confirmation once the transfer is complete.

Step 5: Report the conversion on your tax return. When you file your taxes for that year, you report the conversion on Form 8606. This form tells the IRS how much you converted and how much tax you owe on it. Your custodian will also send you a Form 1099-R showing the conversion amount.

Understanding the tax bill on a backdoor Roth

You owe federal income tax on the amount you convert, calculated at your ordinary income tax rate for that year. If you convert $7,000 and your tax bracket is 24%, you owe roughly $1,680 in federal tax on the conversion. You may also owe state income tax depending on where you live.

The tax is due when you file your return the following year. You do not pay it upfront. However, you can pay it from your regular income or from a refund — the IRS does not require you to pay it from the converted funds themselves.

The larger issue is the pro-rata rule. If you have any other traditional IRA money — from a previous rollover, an old 401(k) conversion, or regular contributions — the IRS treats all your traditional IRAs as one pool for tax purposes. When you convert, you owe tax on a percentage of the total pool, not just the new money you contributed. For example, if you have $30,000 in traditional IRAs and convert $7,000, you owe tax on roughly $7,000 divided by $37,000 (the total), multiplied by the $7,000 conversion. This can make the tax bill much larger than expected.

The pro-rata rule and why it matters

The pro-rata rule is the most common surprise in backdoor Roth conversions. It applies whenever you have a mix of pre-tax and after-tax money in traditional IRAs.

Here is how it works: Suppose you have a $50,000 balance in a traditional IRA from an old 401(k) rollover (pre-tax money). You contribute $7,000 to a new traditional IRA and immediately convert it. The IRS sees $57,000 in total traditional IRA assets. Of that, $50,000 is pre-tax and $7,000 is after-tax (your new contribution). When you convert the $7,000, you owe tax on $50,000 ÷ $57,000 = 87.7% of the $7,000 converted, or about $6,140. You only get $860 into the Roth tax-free.

To avoid this trap, you need to eliminate or move any existing traditional IRA balances before doing a backdoor Roth. Common solutions include rolling a traditional IRA into a 401(k) at your employer (if your plan allows it) or converting all traditional IRA money to Roth in the same year. If you have no other traditional IRAs, the pro-rata rule does not apply and you owe tax only on the conversion amount itself.

Timing and tax year considerations

You can do a backdoor Roth conversion at any time during the tax year. However, the IRS ties the conversion to the tax year in which it occurs. If you contribute to a traditional IRA in December 2024 but do not convert until January 2025, the conversion is treated as a 2025 event for tax purposes.

Most people complete the conversion within a few weeks of the contribution to keep things simple and to avoid market timing issues. If the account value drops between contribution and conversion, you owe less tax. If it rises, you owe more. Doing the conversion quickly minimizes this risk.

You can also do a backdoor Roth conversion for a prior tax year up until the tax filing deadline. For example, you can contribute to a traditional IRA in early 2025 and convert it by April 15, 2025, and report it as a 2024 conversion if you file an amended return. This is useful if you did not realize you exceeded the income limit until after the year ended.

Common mistakes to avoid

The most frequent error is not checking for other traditional IRA balances before converting. Many people forget about old IRAs from previous jobs or do not realize that a SEP-IRA or SIMPLE IRA counts toward the pro-rata calculation. Before you start, list every traditional IRA you own and its current balance.

Another mistake is converting too much money. The annual contribution limit for 2024 is $7,000 ($8,000 if 50 or older). You can only convert the amount you contributed, not more. If you put $7,000 into a traditional IRA and the account grows to $7,500 by the time you convert, you can convert the full $7,500, but the $500 gain is taxable as ordinary income.

A third error is missing the Form 8606 filing requirement. If you do not file Form 8606 with your tax return, the IRS may treat the conversion as a non-may have access to distribution and assess penalties. Always file this form when you do a backdoor Roth conversion, even if you owe no tax.

Frequently Asked Questions

Can I do a backdoor Roth if I have a 401(k) at work?

Yes. A 401(k) does not count toward the pro-rata rule for backdoor Roth conversions. Only traditional IRAs, SEP-IRAs, and SIMPLE IRAs count. If you have a 401(k) and no traditional IRA, you can do a backdoor Roth without worrying about the pro-rata rule. However, if you have both a 401(k) and a traditional IRA, the traditional IRA still triggers the pro-rata rule.

What if I want to convert more than $7,000 in one year?

You can only contribute $7,000 per year to a traditional IRA (or $8,000 if 50 or older). If you want to move more money into a Roth, you would need to use a different strategy, such as a mega backdoor Roth through your 401(k) if your employer plan allows it. That is a separate process with different rules.

Do I have to convert the money right away, or can I wait?

You can wait, but waiting creates risk. If the account grows in value before you convert, you owe tax on the larger amount. If it shrinks, you owe less tax. Most people convert within a few weeks to minimize this uncertainty. There is no rule requiring you to convert immediately, but delaying into the next tax year changes which year the conversion is reported.

What happens if I convert and then my income drops?

You still owe the tax on the conversion amount. The tax bill is based on the conversion amount and your tax bracket for that year, not on whether your income changes later. If you convert $7,000 when you expect to earn $250,000 and then lose your job, you still owe tax on the $7,000 at the rate you calculated when you filed.

Can I undo a backdoor Roth conversion?

You can recharacterize a conversion (move the money back to a traditional IRA) only if you do it before the tax filing deadline for that year, including extensions. After that deadline, the conversion is permanent. If you converted and the market dropped significantly, you could recharacterize, wait, and convert again later at a lower value — but this must happen before the deadline.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.