Step-by-Step Year-End Backdoor Roth IRA Strategy Before December 31

If you earn too much to contribute directly to a Roth IRA, a Backdoor Roth IRA may offer another way to put money into a Roth account. The process involves making a nondeductible contribution to a Traditional IRA and then converting it to a Roth IRA. However, existing IRA balances can make part of the conversion taxable, and the timing matters if you want it to count for the current tax year. With December 31 approaching, here’s how to complete the process, understand the tax implications, and avoid common mistakes.

Who Can Use a Backdoor Roth IRA?

A Backdoor Roth IRA is generally worth considering if your income exceeds the limit for direct Roth IRA contributions but you want to build retirement savings in a Roth account.

Before proceeding, consider three things:

• Your income: There is no income ceiling for converting eligible Traditional IRA funds to a Roth IRA. However, your income may prevent you from contributing directly to a Roth IRA.
• Your compensation: You generally need eligible taxable compensation to make a regular IRA contribution, and your contribution cannot exceed the applicable annual limit.
• Your existing retirement savings: Money in Traditional, SEP, and SIMPLE IRAs can affect how much tax you owe when converting funds to a Roth IRA.

That last point deserves attention. Contributing $7,500 in after-tax money does not automatically make a subsequent $7,500 conversion tax-free. If you have other pre-tax IRA savings, the IRS pro-rata rule generally requires you to account for those funds when calculating the taxable portion.

Review your accounts and estimate the potential tax bill before deciding whether the strategy suits your situation.

How to Complete a Backdoor Roth IRA Before December 31: 8 Steps

If you want your Roth conversion to count for the 2026 tax year, you need to complete the conversion within that calendar year. These eight steps will help you prepare the contribution, handle the conversion, and meet the reporting requirements.

Step 1: Check Your Existing IRA Accounts

Start by reviewing your Traditional, SEP, and SIMPLE IRAs, including accounts you no longer contribute to. Their balances can affect the taxable portion of your conversion.

For example, suppose you have $90,000 in pretax IRA savings and plan to contribute another $7,500 using after-tax money. You might expect to convert the new $7,500 without paying tax on it. However, the pro-rata rule generally prevents you from treating the conversion as though it contains only your new after-tax contribution.

If you have substantial pretax IRA savings, speak with a tax professional before moving forward. One possibility may be rolling eligible pretax IRA funds into an employer-sponsored retirement plan that accepts rollovers. Whether this is suitable depends on your circumstances and the plan’s rules.

Step 2: Make a Nondeductible Traditional IRA Contribution

Once you’ve reviewed your existing accounts, you can make a contribution to a Traditional IRA using money on which you’ve already paid tax.

For 2026, the annual contribution limits for Traditional and Roth IRAs combined are:

These limits apply to your combined regular contributions across all Traditional and Roth IRAs, not to each account separately. Your eligible taxable compensation may impose a lower limit.

When using the Backdoor Roth strategy, you generally make a nondeductible contribution, meaning you do not claim a tax deduction for that contribution.

Keep a record of the amount and the tax year for which you are contributing. If you contribute early in the following calendar year for the previous tax year, confirm that your financial institution records it for the intended year.

Step 3: Confirm the Contribution Has Been Credited

After making the contribution, check your Traditional IRA account to ensure the funds have arrived and been recorded correctly.

Before proceeding, verify three things:

• The contribution has been credited to your Traditional IRA.
• The amount matches what you intended to contribute.
• The contribution has been assigned to the correct tax year.

Financial institutions have different processing times, particularly around holidays. If you’re completing the strategy near December 31, allow enough time for the deposit to clear before requesting the conversion.

Step 4: Convert the Traditional IRA to a Roth IRA

Once the funds are available, request a conversion from your Traditional IRA to your Roth IRA. Your financial institution may let you complete this online or require you to submit a conversion form.

A conversion moves money between retirement accounts. It is different from making a regular contribution directly to a Roth IRA.

If your Traditional IRA contains only your nondeductible contribution, with no earnings or other relevant IRA balances, the conversion will generally be tax-free. If the account has earned interest or investment gains, those earnings may be taxable. Existing pretax IRA funds can also affect the result, as explained in Step 5.

Before submitting the request, confirm the amount you want to convert and check your institution’s processing requirements.

Step 5: Review the Pro-Rata Tax Rule

The pro-rata rule determines how much of your conversion is taxable when your relevant IRA funds include both pre-tax and after-tax money.

The IRS generally considers your combined Traditional, SEP, and SIMPLE IRA balances, along with your after-tax basis, relevant distributions, and conversions. Your December 31 IRA balances for the conversion year also matter.

Consider this example.

Suppose you have $92,500 in pretax IRA funds and make a $7,500 nondeductible contribution. Your total relevant IRA funds are now $100,000, including $7,500 of after-tax basis. If you convert $7,500, you cannot automatically treat the entire conversion as tax-free.

In this example, the nontaxable portion would be approximately $562.50, while the remaining $6,937.50 would generally be taxable. The actual calculation can differ depending on other distributions, conversions, and your tax basis.

Before proceeding, estimate the taxable portion and consider whether the resulting tax bill makes sense for your situation. SD Retirement Plans can help you calculate the amount if you have multiple accounts or substantial pre-tax savings.

Step 6: Handle Any Taxable Earnings

Your Traditional IRA contribution might earn interest or investment gains before you convert it. You can generally convert those earnings along with the original contribution.

For example, suppose you contribute $7,500, and the balance grows to $7,530 before conversion. If you have no other relevant IRA balances and the contribution is entirely nondeductible, the $30 gain will generally be taxable when converted, while the original $7,500 contribution will generally not be taxed again.

You do not need to leave the earnings behind in your Traditional IRA. You can generally convert the full balance and account for any taxable amount when filing your return.

Step 7: Report the Backdoor Roth IRA on Your Tax Return

After completing the conversion, you need to report the transaction correctly.

IRS Form 8606 is used to report nondeductible Traditional IRA contributions and applicable Roth conversions. It helps establish your after-tax basis and calculate the taxable portion of the transaction.

Keep your contribution confirmation, conversion statement, and relevant year-end IRA balances. If you’ve made nondeductible contributions in previous years, retain those Forms 8606 as well, since your existing basis may affect the current calculation.

Your financial institution may provide tax documents, but you should not assume it has completed every reporting requirement on your behalf. You or your tax preparer must ensure the transaction is reported correctly.

If you make a nondeductible contribution for 2026 but convert it in 2027, the contribution and conversion generally belong on different years’ tax returns. The contribution is reported for the year it was designated for, while the conversion is reported for the year it occurred.

Step 8: Complete the Conversion Before December 31

To have your Roth conversion count for the 2026 tax year, it must be completed by December 31, 2026.

Submitting a conversion request on December 31 may not be enough if your financial institution processes it in January. Check its year-end cut-off dates and allow time for transfers and paperwork.

The contribution deadline is different. A qualifying Traditional IRA contribution for 2026 can generally be made by the tax filing deadline in 2027, excluding extensions. However, a Roth conversion completed in 2027 counts as a 2027 conversion, even if the money originally came from a 2026 contribution.

If you want to finish the entire strategy before year-end, aim to complete both transactions well before the final days of December. Save the conversion confirmation once the funds arrive in your Roth IRA.

Common Backdoor Roth IRA Mistakes to Avoid

Even when you follow the steps above, a few oversights can complicate your tax reporting or delay the process. Here’s a closer look at some common mistakes you should avoid:

1. Making a Deductible Contribution Unintentionally

A Backdoor Roth generally uses a nondeductible Traditional IRA contribution. Make sure you do not claim a deduction for the contribution you intend to treat as after-tax basis.

2. Forgetting About Existing SEP, SIMPLE, or Traditional IRA Balances

An old Traditional IRA or a SEP IRA from previous self-employment can affect your conversion. Review all relevant accounts rather than checking only the one you’re using for the new contribution.

3. Ignoring the Pro-Rata Rule

Do not assume you can convert only your after-tax money while leaving pretax funds untouched. Calculate the taxable portion before proceeding.

4. Failing to File Form 8606

Form 8606 helps track your after-tax basis and report applicable conversions. Keep copies of previous filings so you can account for nondeductible contributions made in earlier years.

5. Converting Before the Contribution Is Properly Credited

A contribution request is not necessarily a completed deposit. Confirm that the funds have arrived and are available for conversion before submitting the next transaction.

6. Waiting Until the Final Days of December

Holiday schedules and processing cut-offs can delay transfers. Start early enough to resolve any issues and confirm that the conversion is complete before the year closes.

7. Assuming the Backdoor Roth Is Always Tax-Free

Existing pretax IRA funds and investment earnings can make part of your conversion taxable. Calculate the potential tax cost before moving the money.

Closing Thoughts

A Backdoor Roth IRA can help higher-income earners build Roth retirement savings, but the tax outcome depends on their existing IRA balances and the amount converted. Review your accounts, calculate the potential tax cost, and leave enough time to complete the conversion before December 31. If you have substantial pretax savings or several retirement accounts, consult a qualified tax professional before proceeding.

Frequently Asked Questions