Which Retirement Plan Is Best? 401(k), IRA, Roth, SEP, SIMPLE, 457 and TSP Compared (2026 Limits)

Every common retirement account in one table, with its 2026 limit and the 2027 figure, who can use it, when the money comes out penalty-free, and the order most people should fill them in.

There is no single best plan; there is a best order. For most workers: 401(k) (or 403(b), TSP, 457(b)) up to the employer match, then an IRA (Roth if your income allows it), then back to the workplace plan up to its $24,500 limit for 2026. Self-employed people choose between a SEP IRA and a solo 401(k). Every 2026 limit below is official (IRS Notice 2025-67); 2027 figures are marked until the IRS publishes them.

Last updated 2026-11-04. Sources are linked next to each figure and listed at the end.

Every plan side by side (2026 and 2027 limits)

Employee limits from QuantCalc’s contribution-limits dataset (2026: IRS Notice 2025-67; 2027: 2027 limits dataset; amounts marked projected follow the statutory formulas until the IRS notice is out). Early-withdrawal and RMD rules: IRS exceptions table, IRS RMD FAQs.
Plan	Who can use it	2026 limit	2027	Catch-up (2026)	Income limit	Employer money	Penalty-free access	RMDs
401(k) / 403(b)	Employees of companies (403(b): schools, nonprofits)	$24,500	$25,500 projected	+$8,000 at 50; $11,250 at 60–63	None to contribute	Common	59½ or 55 on leaving	From 73 (not Roth accounts)
TSP	Federal employees and the uniformed services	$24,500	$25,500 projected	+$8,000; $11,250 at 60–63	None	Agency match (FERS)	59½ or 55 on leaving (50 public safety)	From 73 (not Roth)
457(b), governmental	State and local government employees	$24,500 (separate from a 401(k)/403(b))	$25,500 projected	+$8,000; $11,250 at 60–63; special 3-year catch-up	None	Sometimes	No 10% tax after you leave	From 73
Traditional IRA	Anyone with earned income	$7,500 (shared with Roth IRA)	$7,500 projected	+$1,100 at 50	Deduction phases out if you have a workplace plan	No	59½	From 73
Roth IRA	Earned income under the limit	$7,500 (shared)	$7,500 projected	+$1,100 at 50	Phase-out $153,000–$168,000 single, $242,000–$252,000 joint	No	Contributions any time; earnings 59½ + 5 years	None while the owner lives
SIMPLE IRA	Employees of employers with 100 or fewer workers	$17,000	$17,500 projected	Catch-ups (lower than 401(k))	None	Required: match or 2%	59½; 25% tax in the first 2 years	From 73
SEP IRA	Self-employed and small-business owners	Up to 25% of pay, max $72,000	$75,000 projected	None	None	Employer-funded only	59½	From 73
Solo 401(k)	Self-employed with no employees but a spouse	$24,500 deferral + profit share, total $72,000	$75,000 projected	+$8,000	None	You are the employer	59½	From 73

Which account to fill first, and Roth or pre-tax, depends on your tax rate now versus in retirement. Test the whole sequence in a tax-aware plan: Personal PRO — Go PRO — $49 once →

Which plan is best for you?

You have a workplace plan with a match: contribute at least enough to get the full match; it is an immediate return no other account offers.
Then an IRA: a Roth IRA if your modified AGI is under $153,000 single or $242,000 joint for 2026 (Notice 2025-67); above the range, see the backdoor Roth.
Then back to the workplace plan up to $24,500, plus catch-ups from 50.
Government employee with a 457(b): it has its own $24,500 limit on top of a 403(b) or 401(k), and no 10% tax once you leave (IRS).
Self-employed: a SEP IRA is simplest; a solo 401(k) allows more at lower incomes because the employee deferral comes first.
Small employer without a 401(k): a SIMPLE IRA, with a required employer contribution.

What each pre-tax dollar is worth (computed)

A $10,000 pre-tax 401(k) contribution by a single 40-year-old earning $80,000 cuts 2026 federal tax by $2,200 (QuantCalc’s deferral-savings engine on the federal engine copy), so it costs $7,800 of take-home pay. Social Security and Medicare tax are not reduced. The same holds for a 403(b), TSP or 457(b) deferral. Compare your own numbers on the 401(k), 403(b), 457(b) and TSP limit pages.

Paid tool The free tools on this page answer one question at a time. Personal PRO runs your whole retirement in one plan: 10,000 market paths, taxes year by year (federal and every state), Roth conversions, Social Security timing, pensions and annuities next to your portfolio, and a PDF report you keep. A planning tool, not advice: the numbers move when your assumptions do. Go PRO — $49 once → See what Personal PRO includes →

Test your own plan, free: the planner runs your savings, spending, Social Security and taxes year by year across thousands of market paths.

Run the free retirement planner →

Common questions

Which is the best retirement plan?

For most employees: the workplace plan up to the match, then a Roth or traditional IRA, then the workplace plan up to its $24,500 2026 limit. Self-employed: a SEP IRA or solo 401(k). Government workers with a 457(b) can add its separate $24,500 limit.

What is the difference between a 401(k) and an IRA?

A 401(k) is offered by an employer, has a $24,500 employee limit in 2026 and often a match. An IRA is opened by you, has a $7,500 limit and, for a Roth IRA, an income limit (Notice 2025-67).

Can I have a 401(k) and an IRA at the same time?

Yes. The limits are separate. Having a workplace plan can reduce how much of a traditional IRA contribution you can deduct, but not whether you can contribute (IRS Pub. 590-A).

Do Roth accounts have required minimum distributions?

Not while the owner is alive: the RMD rules do not apply to Roth IRAs or designated Roth accounts in 401(k) and 403(b) plans; beneficiaries are subject to them (IRS RMD FAQs).

Sources

Limits are read at build time from frontend/data/contribution-limits-2027/ and research/data/constants-2027-supplement.json; the tax saving is computed by frontend/js/calc/deferral-savings-2026.js. QuantCalc is calculation software, not tax, legal, insurance or investment advice.

All contribution limits, 2026 and 2027 → 2026 401(k) limits → 2026 IRA limits → 457(b) plan and limits → TSP limits and funds → 401(k) withdrawal rules →