Retirement doesn’t end your tax return — it changes how it’s calculated. Instead of wages from a job, income comes from Social Security, retirement account withdrawals, pensions, and investments. Each of those sources follows its own tax rules: some is fully taxable, some is tax-free, and some is taxed at preferential rates. Knowing the rules for each lets you plan around them rather than discover them at filing time.
Quick answer: it depends on the source
Retirement income isn’t treated as one thing by the IRS. Each source has its own treatment:
- Social Security: 0% to 85% may be federally taxable, depending on your other income
- Traditional 401(k) and IRA withdrawals: fully taxable as ordinary income
- Roth 401(k) and Roth IRA withdrawals: tax-free if the rules are met
- Pension income: generally fully taxable as ordinary income
- Required Minimum Distributions (RMDs): ordinary income, no exceptions
- Qualified dividends and long-term capital gains: taxed at preferential rates (0%, 15%, or 20%)
- Part-time work and self-employment: ordinary income, same as during working years
Social Security benefits
Whether your Social Security benefits are taxable depends on a figure the IRS calls “combined income” — sometimes called provisional income. It’s calculated as: your Adjusted Gross Income, plus any tax-exempt interest, plus half of your Social Security benefits.
- Combined income below $25,000 (single) or $32,000 (married filing jointly): no federal tax on Social Security
- Between $25,000–$34,000 (single) or $32,000–$44,000 (joint): up to 50% of benefits may be included in taxable income
- Above $34,000 (single) or $44,000 (joint): up to 85% of benefits may be included in taxable income
Note that “up to 85% taxable” means up to 85% of your benefit amount is added to your taxable income — not that you pay 85% tax on it. The included portion is then taxed at your normal bracket rate.
The income thresholds haven’t been updated since 1983. Because they’re not indexed to inflation, most retirees with any significant other income end up in the 85% range — a detail many people are surprised by.
Traditional 401(k) and IRA withdrawals
Money in a traditional 401(k) or IRA went in pre-tax: you deducted it from taxable income in the year you contributed. When you withdraw, the IRS collects the deferred tax. Every dollar taken out is treated as ordinary income and added to your other income for the year.
This has planning implications. A large withdrawal in a single year can push you into a higher bracket, cause more Social Security to become taxable, and trigger Medicare premium surcharges (known as IRMAA). Spreading withdrawals across multiple years — or doing deliberate Roth conversions in low-income years — can keep more income in lower brackets over the long run.
Roth 401(k) and Roth IRA withdrawals
Roth accounts work in reverse: you contribute after-tax money, so qualified withdrawals come out completely tax-free — the original contributions and all the growth. Qualified withdrawals require:
- The account has been open for at least five years (the five-year rule)
- You are at least 59½ when you withdraw
Roth IRA withdrawals don’t count as income for the combined income calculation that determines Social Security taxability. This makes Roth accounts especially valuable for retirees trying to keep their taxable income below the thresholds.
One note: Roth 401(k)s currently have RMD requirements (though SECURE 2.0 eliminated them for years after 2023 — rules here may still be evolving). Roth IRAs have no RMDs during the original owner’s lifetime.
Pension income
Most pension income is fully taxable as ordinary income in the year you receive it, because contributions were made on a pre-tax basis. Some plans include after-tax contributions from employees — in that case, a portion of each payment isn’t taxable, calculated using an IRS method called the Simplified Method.
Government and military pensions generally follow the same rules, though state tax treatment varies widely. Some states exempt certain pension income entirely.
Required Minimum Distributions
RMDs are mandatory annual withdrawals from traditional IRAs, 401(k)s, and most other pre-tax retirement accounts, starting at age 73 (or 75 for those born in 1960 or later, under current law). They’re taxable as ordinary income whether you need the money or not.
One planning option: Qualified Charitable Distributions (QCDs). If you’re 70½ or older, you can transfer up to $105,000 per year directly from an IRA to a qualified charity. The QCD satisfies your RMD and is excluded from taxable income entirely — it never appears on your return as income. For retirees who give to charity, this is often the most tax-efficient way to do it.
Investment income: dividends and capital gains
Qualified dividends (from most U.S. stocks and some foreign stocks held long enough) and long-term capital gains (assets held more than one year) are taxed at preferential rates: 0%, 15%, or 20%, depending on your total income. Most retirees with moderate income fall in the 0% or 15% range.
Interest income — from savings accounts, CDs, money market funds, and most bonds — is taxed as ordinary income. The same applies to short-term capital gains. This distinction matters when choosing where to hold income-generating assets.
State taxes on retirement income
Federal tax is only part of the picture. States vary widely:
- Some states have no income tax at all (Florida, Texas, Nevada, and others) — retirement income is not taxed
- Some states exempt Social Security from state income tax
- Some states exempt pension income or IRA/401(k) withdrawals up to certain limits
- Others tax everything at ordinary rates, similar to the federal system
If you’re considering a move in retirement, the state tax treatment of your specific income sources — not just the headline rate — is what matters. A state with no income tax on Social Security can meaningfully change the calculation for retirees who depend heavily on it.
Tax planning strategies in retirement
Roth conversions in low-income years
Converting traditional IRA or 401(k) funds to Roth while your income is temporarily lower — in early retirement before Social Security, or in a year with large deductions — can reduce future RMDs and the associated taxable income. The tax is paid now at the lower rate; future withdrawals are tax-free.
Managing withdrawal order
Drawing from taxable accounts first, then traditional accounts, then Roth is often the most tax-efficient sequence — but the optimal order depends on your specific income sources and bracket situation. Consulting a financial planner before starting a systematic withdrawal strategy is often worth the cost.
Qualified Charitable Distributions for RMDs
Redirecting RMDs directly to charity via QCDs eliminates the income, which can lower Social Security taxability and avoid IRMAA surcharges — two meaningful benefits beyond the charitable deduction itself.
Bracket management
Keeping income just below the thresholds that trigger the 85% Social Security taxation tier or IRMAA Medicare surcharges is often worth planning around. Even modest adjustments — reducing a 401(k) withdrawal by $5,000 or moving some income into Roth — can sometimes prevent several thousand dollars in additional tax.
Common mistakes
- Assuming retirement income is mostly tax-free. For most people with traditional retirement accounts, it isn’t.
- Ignoring how 401(k) withdrawals affect Social Security taxability. A large withdrawal can push additional Social Security into taxable territory, creating a tax multiplier effect.
- Missing the Roth five-year rule. Taking Roth distributions before the account has been open five years can create an unexpected tax bill.
- Treating all investment income the same. Interest income and qualified dividends are taxed very differently.
- Not accounting for state taxes when choosing where to retire. State-level retirement income tax rules vary enormously.
What to do next
Map out where your retirement income will come from and what the tax treatment of each source is. Your Social Security statement, pension administrator, and retirement account custodians can each provide projected income figures. From there, a rough tax estimate — or a session with a fee-only financial planner — can show whether strategies like Roth conversions, QCDs, or withdrawal reordering are worth pursuing in your situation.
Further Reading
- How Social Security Benefits Are Taxed
- Roth Conversions Explained
- Tax-Efficient Withdrawal Order in Retirement
- Required Minimum Distributions (RMDs) Explained
- IRMAA: How Income Affects Medicare Premiums
- Capital Gains Taxes Explained
- Standard Deduction vs. Itemizing
This article is for general educational purposes only and does not constitute tax advice. Tax rules change frequently and individual circumstances vary — consult a qualified tax professional or CPA before making decisions based on this information.