Wealthy Pot401(k) Contribution Limits 2027: $25,500 by the IRS Formula
The IRS has not announced the 2027 401(k) limits yet. It does not have to guess, though: the tax code sets a fixed formula, and every input is now public. Applying it to the September 2026 inflation data, the employee contribution limit for 401(k), 403(b), most 457(b) plans and the Thrift Savings Plan comes to $25,500 for 2027, up $1,000 from $24,500, and the age-50 catch-up comes to $8,500, up $500. These are our calculations, not official figures, until the IRS publishes its notice; we will update this page the day it does.
The Short Answer
- 401(k), 403(b), 457(b) and TSP employee limit, 2027: $25,500 by the formula (2026: $24,500).
- Catch-up at age 50 and over, 2027: $8,500 by the formula (2026: $8,000), so up to $34,000 in total.
- Total limit for employee plus employer contributions, 2027: $75,000 by the formula (2026: $72,000).
- SIMPLE IRA and SIMPLE 401(k), 2027: $17,500 by the formula (2026: $17,000).
- Not calculated here: the higher catch-up for ages 60 to 63 ($11,250 in 2026) and the IRA limit ($7,500 in 2026), which follow different rules. The IRS will publish them with the rest.
2027 Limits Next to 2026
| Limit | 2026 (official) | 2027 (calculated) | Change |
|---|---|---|---|
| Employee contributions: 401(k), 403(b), most 457(b), TSP | $24,500 | $25,500 | +$1,000 |
| Catch-up, age 50 and over | $8,000 | $8,500 | +$500 |
| Employee total with the age-50 catch-up | $32,500 | $34,000 | +$1,500 |
| Total additions, employee + employer (415(c)) | $72,000 | $75,000 | +$3,000 |
| SIMPLE IRA / SIMPLE 401(k) employee limit | $17,000 | $17,500 | +$500 |
| Catch-up, ages 60 to 63 | $11,250 | Not yet announced | |
| IRA contribution limit | $7,500 | Not yet announced |
2026: IRS Notice 2025-67 (IR-2025-111). 2027: Wealthy Pot calculation with the statutory formula and BLS CPI-U data, see below.
How We Calculated Them
Section 415(d) of the tax code adjusts these limits each year by inflation, measured with the Consumer Price Index for All Urban Consumers (CPI-U). The method: take a fixed base amount, multiply it by the ratio of the CPI-U average for July through September of this year to the same average in the base year, and round the result down to the multiple the statute sets. Rounding down is why a limit sometimes stays flat for a year even with inflation.
For the employee contribution limit, the base is $15,000 with the third quarter of 2005 as the base period, rounded down to a multiple of $500:
- CPI-U average, July to September 2005: 196.867 (195.4, 196.4, 198.8).
- CPI-U average, July to September 2026: 335.279 (333.918, 334.980, 336.940; September published October 14, 2026).
- $15,000 x 335.279 / 196.867 = $25,546, rounded down to a multiple of $500: $25,500.
The other limits use the same steps with their own base: the age-50 catch-up starts from $5,000 (base 2005, $500 steps), giving $8,515 and so $8,500; the total-additions limit starts from $40,000 (base 2001, $1,000 steps), giving $75,443 and so $75,000; the SIMPLE limit starts from $10,000 (base 2004, $500 steps), giving $17,684 and so $17,500.
To check the method, we ran it for every year from 2019 to 2026 and compared the results with the limits the IRS actually announced. All 32 figures matched exactly. The CPI-U series used here is not seasonally adjusted, and BLS does not revise it, so the inputs will not change before the IRS publishes. The one close call is the catch-up: the formula gives $8,515, only $15 above the $8,500 step, although it stays above the step however the averages are rounded.
What Is Not Known Yet
- The age 60 to 63 catch-up. Since 2025, savers who are 60, 61, 62 or 63 at year end can make a larger catch-up ($11,250 in 2026). Its indexing follows its own rule, and we have not reproduced the IRS figures for it, so we leave it to the official notice.
- IRA limits. The IRA limit ($7,500 for 2026, plus a $1,100 catch-up at 50) is indexed under a different section with a different inflation measure, so this formula does not apply to it.
- Income thresholds such as the Roth IRA phase-out ranges and the wage level above which catch-ups must go into a Roth account ($150,000 for 2026). The IRS sets these in the same notice.
- HSA limits are already official: $4,500 for self-only coverage and $9,000 for family coverage in 2027 (Rev. Proc. 2026-24). See our HSA contribution limits page.
What to Do Now
- Use 2026 for 2026. Contributions for this year still count against $24,500 ($32,500 with the age-50 catch-up). Our 2026 401(k) limits guide covers the rules, including the 60-to-63 catch-up.
- Plan 2027 payroll with care. If you set your 2027 contribution percentage in open enrollment, $25,500 spread over 26 paychecks is about $981 per paycheck (our arithmetic). Confirm against the IRS notice before the first 2027 paycheck.
- Federal employees: the TSP follows the same employee limit. Our TSP calculator shows what a higher contribution adds over time, and the 401(k) calculator does the same for private plans.
Sources & Methodology
- IRS, IR-2025-111 and Notice 2025-67: the official 2026 limits used in the tables.
- 26 U.S.C. 415(d): the cost-of-living adjustment procedure; sections 402(g)(4), 414(v)(2)(C) and 408(p)(2)(E) for the base amounts and rounding of the deferral, catch-up and SIMPLE limits.
- BLS, CPI-U series CUUR0000SA0: monthly index values used in the calculation, including September 2026 (336.940), released October 14, 2026.
- IRS, Rev. Proc. 2026-24: 2027 HSA limits.
Method notes. The 2027 figures are our calculation using the statutory formula and published CPI-U data; we verified the method by reproducing every IRS limit for 2019 through 2026. They are labelled as calculated until the IRS notice is published, and we will replace them with the official figures on the day of the announcement.
This article is for general information and is not tax or investment advice. Figures checked against the primary sources on October 19, 2026.
FAQ
What is the 401(k) limit for 2027?
The IRS has not announced it yet. Applying the formula in the tax code to the September 2026 inflation data gives $25,500, up from $24,500 in 2026.
What is the 401(k) catch-up limit for 2027?
For savers 50 and over, the formula gives $8,500, up from $8,000. The larger catch-up for ages 60 to 63 ($11,250 in 2026) has not been announced.
When will the IRS announce the 2027 limits?
The IRS publishes next year's retirement plan limits each fall, after the September inflation data. We will update this page with the official figures the day they appear.
Will the IRA limit go up in 2027?
It is indexed differently, so this calculation does not cover it. The 2026 IRA limit is $7,500, with a $1,100 catch-up at 50.
Can I contribute the 2027 amount this year?
No. Contributions made through 2026 payroll count against the 2026 limit of $24,500 ($32,500 with the age-50 catch-up). The 2027 limit applies to contributions from your 2027 paychecks.