US Tax Tools

Retirement & 401(k)

Guides on 401(k) contributions, Roth vs Traditional IRAs, Social Security taxation, RMDs, and retirement tax planning strategies.

26 articles

Retirement

Is Social Security Taxable in 2026? Thresholds + Senior Deduction

Up to 85% of Social Security benefits can be taxed. See the 2026 provisional-income thresholds ($25k/$34k single, $32k/$44k MFJ) and the new $6,000 OBBBA senior deduction.

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Retirement

How Social Security Benefits Are Calculated in 2026

How SSA turns your earnings into a monthly check: AIME, the 35-year average, the 2026 PIA bend points, and how full retirement age adjusts your benefit.

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Retirement

Inherited IRA 10-Year Rule 2026: SECURE Act + Final Regs Explained

Non-spouse beneficiaries who inherited an IRA after 2019 must empty the account within 10 years — and after July 2024 final regulations, must also take annual RMDs during years 1-9 if the original owner had reached their RBD. Full mechanics, eligible-designated-beneficiary categories, and worked examples.

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Retirement

QCD 2026: Qualified Charitable Distribution Up to $108,000 from IRA

Qualified Charitable Distributions let IRA owners 70½+ transfer up to $108,000 directly to charity in 2026, satisfying the RMD without taxable income, bypassing the standard-deduction barrier, and stacking with the new $54,000 split-interest QCD option.

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Retirement

Roth Conversion 5-Year Rules 2026: Two Clocks That Trip Up Retirees

Roth conversions trigger TWO separate 5-year clocks under IRC §408A(d). The contribution clock determines tax-free earnings; the conversion clock determines penalty-free access to converted principal. Full mechanics, common confusions, and 2026 worked examples.

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Retirement

RMD Age 73 vs 75: SECURE 2.0 Timeline 2026 Onward

SECURE 2.0 split the RMD starting age by birth year — 73 for those born 1951-1959 and 75 for those born 1960 or later. Mapping who reaches RBD when, the new April-1 first-RMD trap, and the penalty rollback from 50% to 25%/10%.

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Retirement

Roth Conversion + IRMAA 2026: Medicare Premium Cliff Strategy

A Roth conversion adds to MAGI, which can push a retiree across one or more IRMAA cliffs and trigger 2-year-delayed Medicare Part B and Part D surcharges. Full 2026 IRMAA brackets, the 2-year look-back rule, and conversion-sizing strategy to stay under the next tier.

roth ira retirement
Retirement

Roth Conversion Ladder for FIRE: Pre-59½ Tax-Free Access Strategy

A Roth conversion ladder converts Traditional IRA balances year-by-year, then withdraws each converted layer after its 5-year clock — providing penalty-free access to retirement savings before age 59½ without using §72(t). Full 10-year build-out, sequencing math, and how it compares to SEPP.

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Retirement

Roth IRA Pro-Rata Rule 2026: §408(d)(2) Mechanics for Conversion + Backdoor Roth

The pro-rata rule (IRC §408(d)(2)) treats all Traditional IRAs as one aggregated account when computing the taxable portion of any conversion or distribution. This trips backdoor-Roth strategies and partial conversions alike. Full 2026 mechanics, Form 8606 walkthrough, and the 401(k)-rollover workaround.

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Retirement

RMD Table 2026: IRS Uniform Lifetime + Joint Life Tables

Use the 2026 IRS Uniform Lifetime Table to compute Required Minimum Distributions for Traditional IRAs and 401(k)s. Includes age 73-100 divisors, Joint Life Table for younger spouses, and Single Life Table for inherited IRAs.

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Retirement

Mega Backdoor Roth 2026: After-Tax 401(k) to Roth Conversion Guide

How the Mega Backdoor Roth works — the $70k+ §415(c) limit, in-plan vs in-service rollover mechanics, the IRS Notice 2014-54 allocation rule, and when your plan even supports it.

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Retirement

401(k) Catch-Up Age 60-63 Enhanced Contribution 2026 — SECURE 2.0 $11,250 Boost (IRS)

The SECURE 2.0 §109 super catch-up for ages 60-63: $11,250 instead of $7,500 in 2026, the 150% formula, Roth-mandate for high earners from 2026, IRS §415 total cap, and a worked example for a 62-year-old earning $200,000.

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Retirement

2026 Retirement Contribution Limits

2026 projected contribution limits for 401(k), IRA, Roth IRA, HSA, and catch-up contributions compared to 2025. Maximize your tax-advantaged retirement savings with the updated numbers.

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Retirement

2026 Social Security COLA and Tax Changes

The official 2026 Social Security COLA of 2.8%, the new $184,500 taxable wage base cap, and how benefit taxation thresholds affect retirees. What every Social Security recipient needs to know.

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Retirement

401(k) Contribution Limits for 2026

The 2026 401(k) contribution limits, including employee deferrals, catch-up contributions, employer match rules, and how Roth 401(k) fits in.

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Retirement

Backdoor Roth IRA: How High Earners Can Still Fund a Roth

If you earn too much to contribute directly to a Roth IRA, the backdoor Roth strategy lets you get money in anyway. Here's how it works, the tax implications, and the pro-rata rule you need to watch for.

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Retirement

Roth Conversion: When Does It Make Sense?

Learn when converting a Traditional IRA or 401(k) to a Roth makes financial sense — covering low-income years, early retirement gap years, and tax bracket management.

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Retirement

Should You Max Out Your 401(k) or Invest in a Brokerage Account?

Compare tax-deferred 401(k) contributions against taxable brokerage investing to find the right balance for your retirement and financial goals.

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Retirement

Traditional vs. Roth 401(k): Which Should You Pick?

Compare Traditional and Roth 401(k) contributions to determine which option saves you more tax based on your current income, expected future tax rate, and retirement timeline.

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Income Tax

Understanding FICA: Social Security and Medicare Taxes

A complete guide to FICA payroll taxes — the 6.2% Social Security tax, 1.45% Medicare tax, wage base cap, and the Additional Medicare Tax at $200,000.

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Retirement

When to Take Social Security: The Tax Impact of Age 62 vs. 67 vs. 70

Understand how the age you claim Social Security affects your benefit amount, federal tax exposure, and breakeven timeline — and how to minimize the tax hit on your benefits.

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Retirement

When Are Social Security Benefits Taxed? A Complete Guide

Understand when and how Social Security benefits are taxed, including the provisional income formula, 50% and 85% thresholds, and strategies to reduce taxation.

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Income Tax

How FICA Tax Works: Social Security and Medicare Explained

Learn how FICA taxes are calculated, including Social Security and Medicare rates, wage base limits, and the additional Medicare tax for high earners.

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Retirement

Roth vs. Traditional IRA: Which Is Better for You?

Compare Roth and Traditional IRAs to determine which retirement account type best fits your tax situation, income level, and long-term financial goals.

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Retirement

Maximize Your 401(k) in 2025: Contribution Limits and Strategies

Learn the 2025 401(k) contribution limits, catch-up contributions, employer match strategies, and how to calculate the true cost of your retirement savings.

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Planning

The HSA Triple Tax Advantage: The Most Powerful Tax-Sheltered Account

Discover the triple tax advantage of Health Savings Accounts, including 2025 contribution limits, investment strategies, and how to use your HSA as a retirement tool.

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Last updated June 25, 2026 Tax year 2025-26

Data sources: IRS (irs.gov), Social Security Administration

This tool is general information only, not financial advice.

Reviewed by USTax Tools Editorial Desk

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