Updated July 28, 2026. Quick answer: The tax rules are broadly parallel, but a 401(k) is also governed by its plan document, which can be more restrictive than the code permits. Some plans force a lump sum where the code would have allowed ten years.
The plan document is the extra variable
With an IRA, the tax code is effectively the whole story. With a 401(k) there are two rulebooks, and the plan’s may be tighter. A plan is allowed to require faster distribution than the code demands, and some do — occasionally a full lump sum.
That is why a trustee-to-trustee transfer into an inherited IRA is often the first move for a non-spouse: it replaces the plan’s rules with the code’s. Do it as a direct transfer — a non-spouse beneficiary generally cannot do a 60-day rollover, and money that lands in a personal account is usually fully taxable immediately with no way back.
What the 401(k) can offer that an IRA cannot
| Feature | Where it lives |
|---|---|
| Net unrealised appreciation on employer stock | Plan only — lost on transfer to an IRA |
| Stronger federal creditor protection | Generally plan |
| Investment choice and rule clarity | IRA |
If the plan holds appreciated employer stock, transferring it out can forfeit the NUA election permanently. Check the plan’s cost basis before moving anything.
Sources
Final regulations on required minimum distributions, published 19 July 2024; SECURE Act (2019) and SECURE 2.0 (2022); IRC §401(a)(9). Cross-checked July 2026 against professional analyses from Kitces, Grant Thornton, Ascensus, Charles Schwab and Kiplinger. Specific IRS notice numbers for the 2021–2024 waivers, and the exact correction window for reducing the missed-RMD excise tax, should be confirmed against primary source before you rely on them.
This states what the cited authority says. It is not tax advice, and inherited account rules turn on facts about the decedent that no page can verify for you.