My 1099-R just arrived in the mail, which means tax season is officially here. I immediately forwarded it to my CPA, but not before reviewing it myself to make sure everything looked correct. Getting retirement account tax forms wrong can be expensive, so it’s worth understanding what you’re receiving and why.
Here’s your complete guide to every tax form related to 401(k)s and IRAs, what they mean, and what to do with them.
Form 1099-R: Distributions from Retirement Accounts
What It Is
Form 1099-R reports any money you took out of retirement accounts during the year:
- 401(k) withdrawals or distributions
- IRA distributions (Traditional or Roth)
- Rollover transactions
- Required Minimum Distributions (RMDs)
- Early withdrawals (with or without penalty)
Key Information
Box 1 shows the gross distribution—the total amount withdrawn before any taxes or penalties. Box 2a shows the taxable amount (might be less if you have basis in the account). Box 7 is crucial—it’s the distribution code that tells the IRS what type of distribution occurred:
- Code 1: Early distribution (under 59½), subject to 10% penalty
- Code 2: Early distribution, exception applies (no penalty)
- Code 7: Normal distribution (over 59½)
- Code G: Direct rollover (not taxable if done correctly)
- Code J: Early Roth distribution, no known exception
What to Do
- Verify the amounts match your records
- Check that the distribution code is correct
- Provide to your tax preparer or enter into tax software
- If it’s a rollover (Code G), make sure it’s reported as non-taxable
Common Mistake
Rollovers sometimes get reported as taxable distributions if not handled correctly. If you did a direct rollover, make sure it’s coded as “G” and shows $0 taxable amount. If it’s wrong, contact your custodian immediately for a corrected 1099-R.
Form 5498: IRA Contribution Information
What It Is
Form 5498 reports contributions you made to IRAs during the tax year. You’ll receive one from each IRA custodian where you made contributions.
Key Information
- Box 1: Traditional IRA contributions
- Box 10: Roth IRA contributions
- Box 2: Rollover contributions
- Box 13a: FMV (fair market value) of account at year-end
Important Timing Note
Form 5498 arrives in MAY, not in January with your other tax forms. This is because you can make IRA contributions until April 15th for the previous tax year. The form reflects contributions made between January 1, 2025 and April 15, 2026 that count for tax year 2025.
What to Do
You don’t actually need Form 5498 to file your taxes—you can report contributions from your own records. But keep it for your records to prove contributions if ever audited. The IRS receives a copy, so they know what you contributed.
Form 8606: Nondeductible IRA Contributions
What It Is
You file this form (you create it, not your custodian) when:
- You make nondeductible Traditional IRA contributions
- You convert Traditional IRA to Roth (backdoor Roth)
- You take distributions from Traditional IRAs when you have basis
Why It Matters
This form tracks your “basis”—the amount of after-tax money in your Traditional IRA. Without tracking basis, you’ll pay taxes twice on the same money (once when contributed, again when withdrawn). The IRS doesn’t track this automatically—you must file Form 8606 every year you have nondeductible contributions or distributions.
The Backdoor Roth Process
- Contribute to Traditional IRA (nondeductible)
- Convert to Roth IRA
- File Form 8606 Part I to report the contribution
- File Form 8606 Part II to report the conversion
- If done cleanly with no earnings, $0 taxes owed
Common Mistake
Forgetting to file Form 8606 means losing track of your basis. Years later when you take distributions, you won’t be able to prove which portion was already taxed, potentially resulting in double taxation.
Form 1099-DIV & 1099-INT: Investment Income
What They Are
These forms report dividends and interest earned inside taxable investment accounts. You do NOT receive these for retirement accounts (401k, IRA) because those are tax-deferred—you’re not taxed on earnings until withdrawal.
When You’ll Get Them
Only for taxable brokerage accounts. If all your investments are in retirement accounts, you won’t receive these forms.
Form W-2: 401(k) Contribution Tracking
What to Check
Your W-2 from your employer shows 401(k) contributions in specific boxes:
- Box 12, Code D: Elective deferrals to 401(k)
- Box 12, Code AA: Roth 401(k) contributions (post-tax)
- Box 1: Should be reduced by pre-tax 401(k) contributions
Verification
Pull your last paystub of the year and compare YTD 401(k) contributions to Box 12. They should match. If not, contact HR immediately—this affects your taxable income.
Form 5329: Additional Taxes on Qualified Plans
When You Need It
You file Form 5329 if you owe additional taxes on retirement accounts:
- 10% early withdrawal penalty: Took money out before 59½
- 6% excess contribution penalty: Contributed more than the annual limit
- 50% RMD penalty: Failed to take Required Minimum Distribution
Early Withdrawal Penalty (Most Common)
If you withdrew money before 59½ and no exception applies, you owe 10% penalty on top of regular income tax. Form 5329 calculates this additional tax.
Exceptions that avoid the penalty (must be documented):
- First-time home purchase (up to $10,000)
- Qualified higher education expenses
- Substantially equal periodic payments (72(t))
- Disability
- Medical expenses over 7.5% of AGI
Form 8880: Retirement Savings Contributions Credit
What It Is
The Saver’s Credit gives you a tax credit (not just a deduction) for contributing to retirement accounts if your income is below certain thresholds.
2026 Income Limits
- Married filing jointly: Up to $76,500
- Head of household: Up to $57,375
- Single: Up to $38,250
Credit Amount
- 10%, 20%, or 50% of contributions up to $2,000
- Maximum credit: $1,000 ($2,000 married)
This is FREE MONEY if you qualify. Many people miss this credit.
Timeline: When Tax Forms Arrive
| Form | Arrival | Issued By |
|---|---|---|
| W-2 | January 31 | Your employer |
| 1099-R | January 31 | 401(k)/IRA custodian |
| 1099-DIV | January 31 | Brokerage (taxable accounts) |
| 1099-INT | January 31 | Bank/brokerage |
| 5498 | May 31 | IRA custodian |
Common Tax Situations
Scenario 1: Regular 401(k) Contributions Only
Forms you’ll receive:
- W-2 showing reduced Box 1 income and Box 12 Code D with contribution amount
What you do: Nothing special—your taxable income is already reduced.
Scenario 2: Traditional IRA Contribution
Forms you’ll receive:
- Form 5498 (arrives in May)
What you do: Claim deduction on Form 1040, line 20. Reduces taxable income.
Scenario 3: Roth IRA Contribution
Forms you’ll receive:
- Form 5498 (arrives in May)
What you do: Nothing on tax return—Roth contributions aren’t deductible. Keep Form 5498 for records.
Scenario 4: Backdoor Roth Conversion
Forms you’ll receive:
- Form 1099-R showing the conversion
- Form 5498 showing both Traditional contribution and Roth conversion
What you do: File Form 8606 to report the nondeductible contribution and conversion. If done correctly, $0 additional taxes owed.
Scenario 5: 401(k) Rollover to IRA
Forms you’ll receive:
- Form 1099-R with Code G (direct rollover)
- Form 5498 showing rollover contribution
What you do: Report on tax return but verify it’s marked as nontaxable rollover. No taxes or penalties should apply.
What I Actually Do
Every January, I create a tax folder (digital) and collect:
- W-2 from employer
- 1099-R from any distributions or rollovers
- My own records of IRA contributions
- Last year’s Form 8606 (to track basis)
I review each form for accuracy before sending to my CPA. Takes 30 minutes, but I’ve caught errors twice—once a rollover was miscoded as taxable, once my 401(k) contribution amount was wrong on my W-2.
Red Flags That Trigger Audits
- Claiming IRA deduction when income exceeds limits
- Reporting Roth conversion but not filing Form 8606
- Excess contributions (over annual limits)
- Not reporting 1099-R distributions
- Taking RMDs but not reporting them
The Bottom Line
Retirement account tax forms aren’t complicated once you understand what each one means. The key is keeping good records, verifying forms for accuracy, and filing the right forms (especially 8606 for nondeductible contributions).
My 1099-R is now with my CPA, and I’m confident it’s correct because I took 15 minutes to review it first. That’s all it takes—a bit of attention up front saves massive headaches later.
