mega backdoor Roth strategy – Self-employed or run a business with no employees

If you are a business owner with no employees and prefer Roth-style retirement savings, you may want to consider the mega backdoor Roth strategy. This powerful tool allows you to contribute significantly more to a Roth account than the standard Roth IRA or even the regular backdoor Roth route—up to $70,000, or $77,500 if you’re age 50 or older.

Compare that to the regular backdoor Roth limit of $7,000 ($8,000 with the age 50-plus catch-up), and you’ll see why the “mega” title fits.

Here’s the basic idea: You set up a solo 401(k) plan that permits two key features—after-tax contributions and either in-service withdrawals or in-plan Roth conversions. These elements are essential to make the mega backdoor Roth work seamlessly.

Once your plan is in place, you contribute through a combination of

• elective Roth contributions (up to $23,500, or $31,000 if you’re age 50 or older), and
• voluntary after-tax contributions (up to $46,500 in 2025, depending on your plan design and income).

From there, you either roll the after-tax funds into a Roth IRA or convert them inside the solo 401(k) to Roth status.

The benefits of Roth accounts are compelling: tax-free growth, no required minimum distributions, and more flexible estate planning options. Your heirs can inherit Roth funds income-tax-free, although non-spouse beneficiaries must withdraw the funds within 10 years.

While the after-tax value of Roth versus traditional contributions can be similar under constant tax rates, the Roth still offers more control and flexibility—especially valuable if you expect tax rates to rise or want to simplify distributions in retirement.

Bottom line: If you are self-employed, own a corporation, or are a partner in a partnership with no full-time employees, the mega backdoor Roth could be a high-impact retirement strategy.