The current contribution limit for a designated Roth 401(k) account for the 2018 fiscal year is $18,500. In addition, account-holders over the age of 50 may make catch-up contributions of up to $6,000, for a potential total annual contribution of $24,500. Catch-up payments are additional contributions allowed for those nearing retirement age as a means of bulking up the account in the years leading up to its use for regular income.
Although the contribution limits are the same for traditional 401(k) plans and their Roth counterparts, technically a designated Roth 401(k) account is a separate account within your traditional 401(k) that allows for the contribution of after-tax dollars. This means that the elected amount is deducted from your paycheck after income, Social Security and other applicable taxes are assessed; the contribution doesn’t garner you a tax break in the year you make it. On the other hand, no income tax is due on these funds – or their earnings – upon their withdrawal after your retirement. (A traditional 401(k) works in the opposite way: Savers make their contributions on a pretax basis, and pay income tax on the amounts withdrawn once they retire.)