MMC Benefits Handbook
Your Contributions
You can make:
  • Roth 401(k) contributions.
  • before-tax contributions.
  • traditional after-tax contributions.
  • Roth catch-up contributions.
  • catch-up contributions.
Roth 401(k) contributions are calculated as a percentage of your eligible base pay before deductions. These contributions are included in your income for tax purposes, and the income tax withholding amounts will be deducted from the remainder of your pay, not from the contribution amount. Earnings are exempt from taxes if you have maintained a designated Roth account under the Plan (i.e., a Roth 401(k) account or, if earlier, an in-plan Roth conversion account) for at least five taxable years and such amounts are withdrawn when you're at least 59-1/2 (or withdrawn on account of death or total disability).
Before-tax contributions are deducted from eligible base pay before Federal income taxes, and (in most cases) state and local income taxes, are determined. By choosing the before-tax savings option, you pay no income taxes on your contributions or their investment earnings while they remain in the Plan. However, your before-tax contributions (and your traditional after-tax contributions) are included in your gross earnings for purposes of figuring your Social Security and Medicare taxes and benefits.
Some state and local jurisdictions do not recognize before-tax contributions. If you are subject to those rules, state and local taxes will be withheld based on your compensation before reduction for your contributions to the Plan.
After-tax contributions are calculated as a percentage of your eligible base pay before deductions. These contributions are included in your income for tax purposes, and the income tax withholding amounts will be deducted from the remainder of your pay, not from the contribution amount. Earnings on after-tax contributions are tax-exempt while they remain in the Plan.
You may make additional catch-up contributions and/or Roth catch-up contributions during a Plan year, above the maximum annual dollar deferral limit imposed by law, if you will be age 50 or older during the Plan year. Catch-up contributions are deducted from your pay on a before-tax basis. Roth catch-up contributions are deducted from your pay on an after-tax basis.
If you are eligible (or become eligible) to make these additional catch-up contributions and you do not waive them, your catch-up contributions and/or Roth catch-up contributions to the Plan will automatically start after you have reached the IRS annual dollar deferral limit and will stop when you have also met the annual catch-up contribution limit.
2019 Before-Tax and/or Roth 401(k) Limit
$19,000
2019 Annual Catch-up Contribution Limit
$6,000