I have maxed out my Roth IRA contributions each year for five years. However, my work now offers a Roth 401(k). Do they both share the same $5,000 Roth limit? Also, I max out my 401(k) contribution rate each year. — Aubin A.

The contribution limits on Roth IRAs and Roth 401(k)s aren't linked, so you can continue to contribute to your Roth IRA while contributing to a Roth 401(k).

That said, your contributions to a traditional 401(k) plan and a Roth 401(k) are linked — your combined 401(k) contributions can't exceed the annual limit, which this year is $17,000. (That annual limit rises to $22,500 if you are 50 or older and take advantage of these plans' catch-up provisions.)

But even though contributing to a Roth 401(k) plan won't let you save any more for retirement, there are still some advantages including a Roth 401(k) in your savings strategy, says Rick Miller, a certified financial planner and founder of Sensible Financial Planning in Waltham, Mass. Roth 401(k) accounts are similar to Roth IRAs, meaning contributions are made with after-tax funds and withdrawals in retirement are generally tax free. Miller says that if your contributions are limited, consider the Roth 401(k). "The funds you contribute to the Roth 401(k) are worth more in retirement because they're not subject to income tax upon withdrawal," says Miller.

The Roth 401(k) is also more flexible, Miller explains. If you leave your employer, you can roll over the Roth 401(k) to a Roth IRA without triggering a tax liability. You'd have to pay taxes if you rolled a traditional 401(k) into a Roth IRA.

— Austin Kilham

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