Taxes in retirement are different from taxes during your working years — and in some ways more complex. Your income comes from multiple sources, each taxed differently. Decisions about when and how to withdraw from different accounts can mean tens of thousands of dollars in tax differences over a long retirement.
How each income source is taxed
Social Security
Up to 85% of Social Security benefits are taxable at the federal level, depending on your “combined income” (AGI + nontaxable interest + half your Social Security). At combined income above $34,000 (single) or $44,000 (married), 85% of benefits are taxable. Controlling taxable withdrawals from other accounts is the primary lever for reducing Social Security taxation.
Traditional 401(k) and IRA withdrawals
Every dollar withdrawn from a traditional 401(k), 403(b), or traditional IRA is taxed as ordinary income in the year of withdrawal. These withdrawals add to AGI, which can push more Social Security into taxable territory, trigger IRMAA surcharges on Medicare premiums, and push you into higher brackets. Timing and sizing withdrawals carefully — including Roth conversions in low-income years — is the core of retirement tax planning.
Roth IRA and Roth 401(k) withdrawals
Qualified Roth distributions are completely tax-free — and they don’t count toward combined income for Social Security taxation or IRMAA calculations. This makes Roth funds the most tax-flexible asset in retirement: use them in years when you need more income without triggering cascading tax consequences.
Required Minimum Distributions (RMDs)
Starting at age 73 (under current law), you must take minimum distributions from traditional IRAs and most employer plans each year — taxed as ordinary income whether you need the money or not. Large RMDs can push you into higher brackets, increase Social Security taxation, and trigger IRMAA simultaneously. Roth conversions before 73 reduce future RMD size by shifting money out of pre-tax accounts.
Qualified dividends and long-term capital gains
These are taxed at preferential rates: 0% for income up to $47,025 (single) or $94,050 (married) in 2024, 15% above those thresholds, 20% for very high earners. In lower-income retirement years, you may be able to realize significant capital gains at 0% — a meaningful planning opportunity.
Pension income
Most pension income is taxed as ordinary income. If you contributed after-tax dollars, a portion of each payment may be tax-free (the exclusion ratio) — check with your pension administrator.
How IRMAA intersects with retirement income
IRMAA adds surcharges to Medicare Part B and Part D premiums for higher-income beneficiaries. In 2025, surcharges begin at MAGI above $106,000 (single) or $212,000 (married). IRMAA uses income from two years prior — a large Roth conversion or asset sale this year could trigger surcharges two years later. Roth withdrawals, HSA withdrawals, and return-of-basis payments don’t count toward MAGI for IRMAA, making them valuable tools for managing the threshold.
The enhanced standard deduction for seniors
Retirees 65 and older receive an enhanced standard deduction — an extra $1,950 per person (single) or $1,550 per person (married, per qualifying spouse) in 2024. Many retirees with moderate income pay little or no federal income tax as a result. If your income is low enough that the standard deduction covers most of it, your effective tax rate in retirement may be lower than expected.
State taxes on retirement income
- 9 states have no income tax: Alaska, Florida, Nevada, New Hampshire, South Dakota, Tennessee, Texas, Washington, Wyoming
- Many states exempt Social Security benefits from state tax
- Some states have senior-specific pension or retirement income exemptions
- A few states tax all retirement income as ordinary income
For retirees considering relocation, state tax treatment of retirement income can be a meaningful factor — potentially $3,000–$6,000 per year in savings in high-tax vs. no-tax states.
Key tax strategies for retirees
- Roth conversions in low-income years — convert pre-tax money to Roth when income is low (before RMDs begin), paying tax at lower rates now to avoid higher rates later
- Tax-bracket filling — deliberately withdraw enough from pre-tax accounts each year to fill lower brackets, reducing future RMD size
- 0% capital gains harvesting — if income is below the 0% threshold, sell appreciated assets and repurchase them, resetting cost basis tax-free
- Qualified Charitable Distributions (QCDs) — if 70½+ with an IRA, donate up to $105,000/year directly from your IRA to charity; satisfies your RMD but is excluded from taxable income
- Strategic Social Security timing — delaying Social Security while converting pre-tax accounts to Roth can reduce lifetime taxes significantly
Bottom line
Retirement taxes reward proactive planning. Social Security, RMDs, traditional IRA withdrawals, and IRMAA all interact in ways that punish inaction. Roth conversions, QCDs, bracket filling, and 0% capital gains harvesting are the core tools. A fee-only financial planner or CPA with retirement tax experience can help you build a withdrawal strategy that minimizes lifetime taxes across all your accounts.
Further Reading
- Tax-Efficient Withdrawal Order in Retirement
- Roth Conversions Explained
- Required Minimum Distributions (RMDs) Explained
- IRMAA: How Income Affects Medicare Premiums
- How Social Security Benefits Are Taxed
- How to Reduce Taxes on Social Security Benefits
This article is for general educational purposes only and does not constitute financial, tax, or legal advice. Consult a qualified financial advisor, tax professional, or attorney for guidance specific to your situation.