Roth In-Plan Conversion: A Powerful Strategy for Tax-Smart Retirement Planning

Roth in-plan conversions, also referred to as in-plan Roth conversions or in-plan Roth rollovers, offer a practical solution in today’s ever-changing retirement planning landscape. 

For employer-sponsored retirement plans like 401(k)s, 403(b)s, or the Thrift Savings Plan (TSP), participants can shift money from their traditional pre-tax retirement accounts to a Roth account within the same plan. Those planning to retire in a higher tax bracket or seeking tax flexibility can use this strategy to increase their overall tax flexibility.

Call us today to speak to one of our ARQ Wealth advisors about your Roth In-Plan Conversion.

Why One Should Consider a Roth IRA

A Roth IRA is an excellent retirement savings option because it promises tax-free income in retirement. Traditional IRAs offer a tax deduction on contributions, allowing taxpayers to reduce their taxable income and defer ordinary income tax, but Roth IRAs are funded with after-tax dollars—meaning you pay taxes now in exchange for tax-free withdrawals later. 

Roth IRAs allow tax-free withdrawals, including earnings (as long as the account owner is at least 59 ½ and the account has been open for at least 5 years).

Not having to take required minimum distributions (RMDs) during your lifetime is one of the best benefits of a Roth IRA. Traditional IRA holders are required to start withdrawing funds at age 73 if born between 1951 and 1959 (those born in 1960+ have an RMD age of 75). This creates taxable income and can push retirees into a higher tax bracket. It also has the potential to increase Medicare premiums. 

A Roth IRA allows you to grow tax-free money for an unlimited amount of time. This gives you greater control over your withdrawals and lets your money grow longer if you don’t need it right away.

This also makes Roth IRAs especially effective for estate planning. A Roth IRA can be a valuable asset to leave to heirs for tax-free distributions (since most non-spouse heirs are subject to the 10-year withdrawal rule under the SECURE Act). 

Because the original owner of the Roth IRA has no lifetime RMDs, the account can be passed on with a larger, untaxed inheritance. In contrast, inherited traditional IRAs often impose income tax burdens on beneficiaries, reducing the inheritance.

Although the tax consequences of a Roth IRA conversion may seem counterintuitive—you owe income tax on the market value at the time you convert to a Roth—the long-term tax implications can work in your favor. Paying taxes now means all future growth and qualified withdrawals are completely tax-free.

Conversions in particular years may be more tax-advantaged than in other years. For example, if your income is variable and comparatively lower due to a job change, early retirement, a gap in employment, or a market downturn, you may be able to convert and pay taxes at a lower rate. In years of successive market downturns, the value of what you are taxed on will be less, and any future increase in value will be available in the Roth tax-free.

For instance, converting during a downturn means paying taxes on a reduced balance, positioning you for greater tax-free appreciation when values recover. This can outweigh the initial tax hit over the long term, especially if you expect higher future rates due to policy changes or personal circumstances.

What Is a Roth In-Plan Conversion?

A Roth in-plan conversion involves transferring eligible funds from the traditional (pre-tax) portion of your employer-sponsored retirement plan to the Roth (after-tax) portion within the same plan. Unlike a complete rollover to a Roth IRA, the assets remain in the employer plan, avoiding the need to transfer money externally.

This option became more widely available following legislative changes, such as the American Taxpayer Relief Act of 2012 and the SECURE Act 2.0, which permit this in qualified plans that choose to offer it.  

For example, the federal Thrift Savings Plan (TSP) began allowing in-plan Roth conversions effective January 28, 2026, enabling participants to convert vested traditional balances to Roth balances directly.

Not all plans offer this feature, as it is at the plan sponsor’s discretion; however, many large providers, including Fidelity, Vanguard, and Empower, support it where permitted. The conversion considers the transferred amount as a taxable distribution for the year, even though the funds never leave the plan.

Key eligibility typically includes:

• Having a vested traditional balance.
• Meeting any plan-specific minimums (e.g., TSP requires a $500 minimum per conversion).
• No income limits apply, unlike direct Roth IRA contributions.

This differs from a traditional Roth IRA conversion, in which funds are moved from a traditional IRA (or sometimes a 401(k) via rollover) to a Roth IRA. In-plan versions keep assets within the employer plan, preserving benefits such as low fees, creditor protection, and plan-specific investment options.

Roth conversion rules for in-plan moves follow IRS guidelines: The converted pre-tax amount, plus any earnings on after-tax contributions, are taxable in the year of conversion. No early 10% withdrawal penalty applies to the conversion itself, since it’s not considered a distribution outside the plan.

How to Do a Roth In-Plan Conversion

Performing an in-plan Roth conversion is straightforward in plans that allow it, often done online through your plan’s portal.

1. Check plan availability. Log in to your account or contact your plan administrator to confirm if in-plan conversions are offered.
2. Determine eligible amounts. You can usually convert vested pre-tax contributions, rollover amounts, employer matches (if vested), and earnings. Some plans also allow after-tax contributions (useful in “mega backdoor Roth” strategies).
3. Select the amount. Choose a dollar amount or percentage, subject to minimums (e.g., $500 in TSP) and any “leave-behind” rules to maintain small balances in certain sources.
4. Complete the request. Submit via the plan’s website or app. Many allow multiple conversions per year (up to 26 in TSP).
5. Handle taxes. Since the taxable portion increases your income, consider withholding or paying estimated taxes to prevent underpayment penalties. If you withhold taxes during the conversion and you are under 59.5 years old, the 10% early withdrawal penalty will apply to the amount withheld.
6. Monitor the five-year rule. Each conversion has its own five-year clock for penalty-free earnings withdrawals (though contributions are always accessible tax and penalty-free if qualified).

Unlike Roth IRA conversions, in-plan versions generally cannot be recharacterized (undone). Once completed, it’s permanent, so careful planning is essential.

Benefits of Roth In-Plan Conversion

The main appeal is timing your tax payments: pay taxes now to potentially benefit from tax-free status later.

Key advantages include

• Tax-free growth and qualified withdrawals. After paying taxes on the conversion, future earnings grow tax-free. Qualified distributions (after age 59½ and a five-year holding period) are completely tax-free, including earnings.
• No required minimum distributions (RMDs). Roth accounts within plans are not subject to RMDs during the owner’s lifetime, unlike traditional accounts, which begin at age 73. This enables ongoing tax-free growth.
• Tax diversification. Mixing pre-tax and Roth assets offers flexibility in retirement. Take withdrawals from Roth accounts during high-tax years or to manage taxable income for Social Security, Medicare premiums, or other needs.
• Estate planning perks. Heirs inherit Roth accounts tax-free (subject to distribution rules), potentially reducing their tax burden.
• No early withdrawal penalty on conversion. The process avoids the 10% penalty that might apply to direct distributions.
• Convenience. Funds stay in the plan, maintaining low costs, familiar investments, and protections without opening a separate IRA.

This strategy works well if you expect higher tax rates in retirement (due to bracket creep, rising rates, or large RMDs), are in a lower bracket now, or want to maximize tax-free legacy transfers. It’s especially helpful for high earners who are maxing out contributions and want additional Roth exposure beyond annual limits.

Examples of Roth In-Plan Conversions in Action

Consider these scenarios:

1. Mid-career professional in a 401(k). A 45-year-old earning $150,000 expects future promotions and a higher income. They convert $50,000 from a traditional to a Roth in-plan during a moderate-income year. They currently pay taxes at 24% (about $12,000, possibly spread over multiple years). By retirement, that $50,000 plus growth (assuming a 7% annual return over 20 years) could exceed $193,000 tax-free.
2. TSP participant post-2026 change. A federal employee with a large traditional TSP balance converts portions annually (up to 26 times/year) to build Roth savings. This avoids leaving the low-cost TSP while still allowing tax-free withdrawals and avoiding RMDs.
3. After-tax “mega backdoor” user. Under a plan that allows high after-tax contributions, an investor contributes above the deferral limit and then converts the contribution to a Roth in-plan. Earnings are taxed minimally, but all future growth becomes tax-free—potentially adding tens of thousands in Roth annually.

These examples demonstrate how conversions can maximize tax benefits, but results vary based on individual factors, including current versus future rates, investment returns, and plan rules.

Are Roth In-Plan Conversions Available in Arizona?

There’s no Arizona-specific state law prohibiting or mandating the Roth in-plan conversion. Availability hinges on your employer’s plan sponsor decisions, often influenced by the plan provider (e.g., Fidelity, Vanguard, Nationwide).

How to Check If Your Plan Allows It

1. Log in to your retirement plan account (e.g., via your provider’s website).
2. Review the plan documents, SPD, or investment options for mentions of “Roth designated account,” “in-plan Roth rollover,” or “in-plan conversion.”
3. Contact your HR department, plan administrator, or call the provider directly—they can confirm eligibility and any rules (e.g., minimum amounts, frequency).
4. If unavailable in-plan, you might roll over to a Roth IRA (after leaving employment or if in-service withdrawals are allowed), but that’s not the same as keeping funds in the plan.

Since plan rules vary widely—even among Arizona employers—the best step is verifying with your specific plan. If you’re exploring this for tax diversification or long-term benefits, it’s often worthwhile.

Considerations and Potential Drawbacks

Although Roth in-plan conversions are powerful, they aren’t suitable for everyone. The initial tax bill can be large, especially with significant conversion amounts, which might push you into a higher tax bracket or impact your deductions and credits. State taxes may also apply, and once conversions are made, they can’t be undone.

It’s wise to model scenarios and work with a financial advisor to perform a tax analysis and compare paying taxes now versus later, factoring in expected growth and tax rates.

Final Thoughts

A Roth in-plan conversion offers a smart way to create tax-free retirement income, boost flexibility, and get ready for a changing tax landscape. Whether through direct pre-tax moves or after-tax strategies, it helps many take control of their tax future.

For personalized guidance on whether this suits your situation, including your plan eligibility and the best timing, contact the experts at ARQ Wealth. Our team specializes in tax-efficient retirement strategies and can help you understand Roth conversion rules, explore options, and implement a plan that matches your goals. 

Reach out to ARQ Wealth today to learn more and start optimizing your retirement savings.