The 401k catch-up math nobody runs for you at 50.

The catch-up contribution after 50 is not a perk. It's the difference between "comfortable retirement" and "working until 73." Here's the actual math, the Secure Act 2.0 changes, and the three moves that compound at midlife.

The mental model most 50-year-olds carry into retirement planning was written for the 35-year-old version of themselves. Save 15% of income. Index funds. Don't panic during corrections. All of that is still true, and almost none of it is the actually-decisive move at midlife.

The decisive move is the catch-up contribution, the Roth conversion window, and the household tax-bracket arbitrage. The first one alone — used consistently from 50 to 65 — adds roughly $300,000 to the median 401k balance in our run of the numbers. The second can save six figures in lifetime tax. The third is the one most CPAs don't bring up unless you ask.

The catch-up math, run honestly

The 2026 IRS limits: $23,500 standard 401k contribution. $7,500 additional catch-up for ages 50-59. A new $11,250 "super catch-up" for ages 60-63 under Secure Act 2.0. After 63, the catch-up reverts to the standard amount.

Here is what consistent use of the catch-up does, assuming 7% real return:

Most 50-year-olds we talk to know the catch-up exists in the abstract. Far fewer have actually changed their payroll deduction to use it. The default contribution rate set at age 35 is still running for them. The fix is one HR form.

The Roth conversion window

The lowest-income years of most professional lives are typically 62-68 — between leaving full-time work and starting Social Security and Required Minimum Distributions. Most people don't realize this is the cheapest tax-bracket window they'll ever have.

Strategic Roth conversions in this window — moving traditional IRA dollars into Roth and paying tax at the lower bracket — can flatten the lifetime tax curve dramatically. The qualitative move: convert just enough each year to stay in the 22% federal bracket. Run for 5-7 years. Tax-free growth from there. Tax-free withdrawals in retirement. No RMDs on Roth dollars.

The household tax-bracket arbitrage

If you and a spouse are both working: who contributes pre-tax and who contributes Roth matters more than most people realize. The higher earner usually gets more value from pre-tax (deduction at higher bracket today). The lower earner often gets more value from Roth (tax-free withdrawals later, especially if you expect bracket parity in retirement).

This is a 20-minute conversation with a fee-only fiduciary. It is not a conversation most commission-based advisors are eager to have — there's no product to sell at the end of it.

What we'd actually do this week

• Today: log into your 401k provider, change your contribution percentage to capture the full $23,500 + $7,500 catch-up. If your employer's payroll system requires HR, email HR today.
• This week: read Die With Zero by Bill Perkins. It is the single book that reframes midlife money decisions most usefully. (Linked below; we earn a small commission if you buy through it.)
• This month: if you have a traditional IRA over $200k, book one paid session with a fee-only fiduciary (typically $300-$600 for a flat-fee consult) and ask specifically about Roth conversion runway.
• This quarter: consolidate orphaned 401k accounts from former employers into a single IRA. The administrative simplification compounds — and most of those old accounts are in expensive default funds.