Annuity vs 401k:
Which Is Better
for Your Retirement?

Both accounts serve retirement, but they serve different phases of it. A 401k is built for accumulation: tax-deferred growth, employer matching, and contribution limits up to $23,500 per year make it unmatched as a savings vehicle. An annuity is built for distribution: it converts a lump sum into guaranteed monthly income you cannot outlive, no matter how long markets stay flat or how long you live. The question of which is "better" is really a question of which phase you're in. Use our free annuity payout calculator to see exactly how much monthly income your 401k balance could generate today.

How Much Does a $500,000 401k Pay as an Annuity vs the 4% Rule?

A 65-year-old rolling $500,000 from a 401k into a single-premium immediate annuity (SPIA) receives approximately $2,650–$2,900 per month for life in 2026, based on quotes from A-rated insurers. The 4% withdrawal rule applied to the same $500,000 yields only $1,667 per month — a gap of nearly $1,000 per month. That difference exists because annuities pool longevity risk across thousands of retirees and pass mortality credits to survivors, allowing insurers to pay substantially more per month than a simple interest-based withdrawal calculation. The tradeoff is irreversibility: once annuitized, the lump sum is gone.

401k vs Annuity Taxes: Which Costs More in Retirement?

Tax treatment is where most comparisons miss critical detail. A traditional 401k funded with pre-tax contributions is fully taxable as ordinary income on every withdrawal. A qualified annuity funded by a 401k rollover carries the exact same tax treatment — the entire monthly payment is taxable. The transfer itself is tax-free; only the distributions trigger taxes. Non-qualified annuities (funded with after-tax dollars) are more tax-efficient: only the earnings portion of each payment is taxable, following the IRS exclusion ratio method.

There is one significant 401k-specific tax risk: required minimum distributions. According to the IRS (2024), 401k RMDs must begin at age 73 under the SECURE 2.0 Act — forcing taxable withdrawals even when you don't need the income. An annuity avoids this problem for the annuitized portion, since payments are already structured as income. For a $500,000 balance at age 73, the first-year RMD is approximately $18,900, potentially pushing retirees into a higher bracket.

Annuity or 401k for Retirement Income: A Decision Framework

The answer depends on one key variable: how much guaranteed income you already have. If Social Security and a pension cover your fixed monthly expenses, keeping 401k assets liquid and invested for growth or legacy makes more sense. If you have no pension — which describes roughly 85% of private-sector workers — an annuity covering your baseline expenses (housing, utilities, healthcare) provides a guaranteed income floor that nothing else replicates. A 65-year-old woman has a median life expectancy of 86, meaning 21 years of withdrawals; sequence-of-returns risk is real over that span. An annuity eliminates it entirely for the portion you convert.

A practical split: convert enough of your 401k to cover fixed monthly costs — say $2,500/month — and leave the rest invested for flexibility. This approach layers guaranteed income over Social Security without sacrificing access to liquid assets for emergencies or discretionary spending.

The Mistake Most Retirees Make When Comparing Annuity vs 401k

Most retirees underestimate how much the starting age shifts the annuity income equation. Converting at 60 instead of 65 reduces monthly income by roughly $400–$500 on a $500,000 SPIA — that's up to $6,000 less per year, every year, for the rest of your life. Waiting from 65 to 70 adds a similar margin in the other direction. The second most common mistake is comparing a life-only annuity quote to a joint-and-survivor 401k withdrawal plan. A joint-and-survivor SPIA reduces monthly payments by $400–$500 compared to a single-life contract, but it continues income to a surviving spouse for life — a benefit that has enormous real dollar value and is easy to overlook when staring at two monthly income numbers.

Always get quotes from at least three A-rated carriers before converting. Payout rates can vary by 8–12% between insurers for identical contracts on the same purchase date. For a $500,000 contract, that spread is worth $200–$300 per month — roughly $60,000 over a 20-year retirement.