Rolling Over a 401(k): Tax Rules and Mistakes to Avoid

When you leave a job, you have several options for your 401(k). Rolling it over to an IRA or new employer plan can give you more investment options and simplify your retirement accounts—but getting it wrong can trigger unexpected taxes and penalties. If you are comparing plan types, review 403(b) vs 401(k) and 457(b) rules.

Key Takeaways

• Direct rollovers (trustee-to-trustee) avoid taxes and the 20% withholding.
• Rolling Traditional 401(k) to Roth IRA triggers taxes on the full amount.
• Some reasons to keep your 401(k): creditor protection, NUA strategy, early access.

Your 401(k) Rollover Options

When you leave an employer, you typically have four choices:

Option	Pros	Cons
Leave it	Simple, no action needed	Limited investment options, multiple accounts
Roll to new employer 401(k)	Consolidation, possibly better funds	Not all plans accept rollovers
Roll to Traditional IRA	Full investment freedom, consolidation	Loses some 401(k) protections
Roll to Roth IRA	Tax-free growth going forward	Taxable now, need cash to pay taxes
Cash out	Immediate access	Taxes + 10% penalty if under 59½

Direct vs Indirect Rollovers

Direct Rollover (Recommended)

Money moves directly from your 401(k) to the new account:

• No taxes withheld
• No 60-day deadline pressure
• Check is made payable to the new custodian “FBO” (for benefit of) you

How to do it:

1. Open your IRA (or confirm new 401(k) accepts rollovers)
2. Get the receiving account details
3. Contact your old 401(k) plan and request a direct rollover
4. Provide the receiving account information

Indirect Rollover (60-Day Rollover)

You receive a check and deposit it yourself:

• 20% mandatory withholding for taxes
• Must deposit 100% of the original balance within 60 days (even the withheld 20%)
• Miss the deadline = taxes + potential penalty

Example of the problem:

• 401(k) balance: $100,000
• Check you receive: $80,000 (after 20% withholding)
• You must deposit: $100,000 within 60 days
• If you only deposit $80,000: $20,000 is treated as a taxable distribution

Recommendation: Always use direct rollover to avoid this complexity.

Tax Consequences by Rollover Type

Traditional 401(k) → Traditional IRA

• Taxes: None (both are pre-tax)
• Penalty: None
• Forms: 1099-R from 401(k), 5498 from IRA

Traditional 401(k) → Roth IRA

• Taxes: Full amount is taxable income in the year of conversion
• Penalty: No 10% penalty (it’s a conversion, not a distribution)
• Planning: Consider doing this in a low-income year

Example: Roll $100,000 from Traditional 401(k) to Roth IRA

• $100,000 added to your taxable income
• At 24% bracket: ~$24,000 in federal taxes
• But: Tax-free growth and withdrawals going forward

If you want a staged approach, consider a Roth conversion ladder and compare the impact against your marginal tax rate.

Roth 401(k) → Roth IRA

• Taxes: None (both are Roth)
• 5-year rule: Your Roth 401(k) holding period transfers if your Roth IRA was opened 5+ years ago; otherwise, the clock restarts

Traditional 401(k) → New Employer 401(k)

• Taxes: None (pre-tax to pre-tax)
• Benefit: Consolidation, possibly better creditor protection
• Requirement: New plan must accept rollovers

When to Keep Your 401(k)

Don’t automatically roll over. Consider keeping your 401(k) if:

1. You’re Between 55-59½

If you separate from service in the year you turn 55 or later, you can take penalty-free withdrawals from that employer’s 401(k). Roll to an IRA, and you lose this benefit until 59½.

2. You Have Company Stock (NUA)

If your 401(k) holds highly appreciated company stock, the Net Unrealized Appreciation strategy can save significant taxes.

See: NUA Tax Strategy

3. You Want Maximum Creditor Protection

401(k)s have unlimited federal creditor protection. IRAs have strong but slightly weaker protection (varies by state).

4. The Funds Are Better/Cheaper

Some 401(k) plans have access to institutional share classes not available to retail IRA investors.

When to Roll to an IRA

Roll to an IRA if:

• You want broader investment choices (individual stocks, specific ETFs)
• Your 401(k) has high fees or poor fund selection
• You want to consolidate multiple old 401(k)s
• You’re planning backdoor Roth (but see pro-rata rule below)

The Pro-Rata Rule Warning

If you have pre-tax IRA balances and want to do a backdoor Roth IRA, rolling a 401(k) to a Traditional IRA creates a pro-rata problem.

Example:

• You roll $200,000 from 401(k) to Traditional IRA
• You also have $7,000 non-deductible IRA contribution for backdoor Roth
• Total IRA balance: $207,000
• After-tax percentage: $7,000 / $207,000 = 3.4%
• If you convert $7,000: Only 3.4% ($238) is tax-free; 96.6% ($6,762) is taxable

Solution: Keep 401(k) money in a 401(k) (your current or new employer), not an IRA.

See: Pro-Rata Rule

Step-by-Step: How to Roll Over

Rolling to an IRA

1. Open an IRA at your preferred brokerage (Fidelity, Vanguard, Schwab, etc.)
2. Get account details: Account number, mailing address, and DTC number
3. Contact your 401(k) plan: Request a direct rollover to your new IRA
4. Provide paperwork: Most plans have a distribution request form
5. Specify rollover type: Direct rollover to IRA (not cash distribution)
6. Wait and verify: Funds typically arrive in 1-2 weeks
7. Invest the funds: Money may arrive as cash; invest per your strategy

Rolling to a New 401(k)

1. Confirm your new plan accepts rollovers (ask HR or check plan documents)
2. Get new plan details: Plan name, EIN, and where to send funds
3. Request direct rollover: From old plan to new plan
4. Follow up: Make sure funds arrive and are invested properly

Common Mistakes to Avoid

1. Taking an Indirect Rollover and Missing the 60-Day Deadline

Once you receive a check, the clock starts. Set reminders and act fast.

2. Forgetting About the 20% Withholding

If you do an indirect rollover, you need to come up with the withheld 20% from other funds to avoid a taxable distribution.

3. Creating Pro-Rata Issues

Rolling to a Traditional IRA can complicate backdoor Roth strategies.

4. Not Updating Beneficiaries

When you open a new IRA, designate beneficiaries. Don’t assume the old 401(k) designations transfer.

5. Cashing Out Instead of Rolling Over

A cash-out before 59½ means income taxes + 10% penalty. On $100,000, that could be $30,000+ gone.

DIY Checklist: Forms + Questions

Forms you’ll see

• Form 1099-R from your old 401(k) (Box 7 code G = direct rollover)
• Form 5498 from your IRA confirming the rollover
• Form 8606 if any Roth conversion is involved

Questions to answer before rolling over

• Am I between 55-59½ and might need penalty-free access?
• Do I have company stock eligible for NUA?
• Do I plan to do backdoor Roth conversions?
• What are the fees and fund options in my current 401(k)?
• Does my new employer’s plan accept rollovers?

Related Guides

• Backdoor Roth IRA
• NUA Tax Strategy
• Roth Conversion Ladder
• Pro-Rata Rule
• AGI vs MAGI

How sharper.tax Helps

When you upload your tax return to sharper.tax, we analyze your retirement contributions, income, and filing status to identify the best rollover path for your situation. We flag pro-rata issues, evaluate Roth conversion opportunities, and model the tax impact of different rollover strategies. Sophisticated tax planning used to require a high-end CPA---we make it available for free.

Sources

• IRS Rollover Chart
• IRS Publication 590-A (Contributions to IRAs)
• IRS Publication 575 (Pension and Annuity Income)
• IRS Topic 413 (Rollovers from Retirement Plans)

---

The information above is educational and not tax advice.