How Your 401(k) Affects Your Paycheck

A traditional or designated Roth payroll deduction can change cash net pay and one or more taxable-wage bases. The current-paycheck result depends on the deduction treatment you enter, the plan's eligible compensation, withholding forms, YTD wages, and jurisdiction.

This guide does not publish contribution limits or tax outcomes as certified facts because the approved archive does not yet contain the required current federal retirement source family or complete state conformity evidence.

Facts to verify before estimating

Plan type: traditional and designated Roth deductions are separate elections.
Eligible compensation: the plan decides which wages the percentage applies to.
Wage-base treatment: verify federal income-tax, Social Security, Medicare, state, and local treatment separately.
YTD contributions: include prior payroll deductions, other employers or plans, and any applicable catch-up facts.
Plan terms: match, vesting, funding, eligibility, and excess correction are not paycheck-calculator decisions.

Do not assume federal and state treatment match

A deduction's federal payroll treatment does not prove its treatment in every state or locality. TakeHome IQ has selected jurisdiction-specific overrides, but the certification matrix does not establish category-complete conformity nationwide. Confirm the applicable state rule before relying on the estimate.

Current paycheck versus annual plan limits

TakeHome IQ models the entered fixed or percentage deduction for the current paycheck. It does not determine remaining annual contribution room, shared limits across employers or plan types, employer match or annual additions, excess deferral corrections, or final return liability. Some configured catch-up behavior uses age and prior-year FICA wages from this employer; verify the current federal rule.

How to compare entered scenarios

Start from the same paycheck inputs and verified plan compensation.
Enter a traditional deduction in one scenario and a Roth deduction in another.
Keep withholding forms, YTD wages, jurisdictions, and other deductions unchanged.
Compare projected taxable wages, withholding lines, total deductions, and net pay.

The app does not provide a one-tap traditional/Roth conversion or decide which option is better. A scenario delta shows the effect of the treatments entered, not investment advice or a guarantee of qualified future distributions.

Frequently asked questions

Does a traditional 401(k) reduce every paycheck tax?

No. Confirm its treatment for federal income-tax, Social Security, Medicare, state, and local wages separately. State conformity and other wage-base facts can change the result.

Does TakeHome IQ track my remaining annual contribution limit?

No. It models the deduction entered for the current paycheck. It does not maintain a complete YTD contribution ledger across employers and plans or determine excess-correction obligations.

Can the app tell me whether traditional or Roth is better?

No. You can model separately entered deductions, but plan eligibility, qualified distributions, future tax treatment, match, vesting, and personal financial goals are outside a paycheck estimate.