At what age can i no longer contribute to a 401k?

This 72-year requirement applies to most retirement accounts, including traditional IRAs, SEP and SIMPLE IRAs, Physical Gold IRAs, and qualified plans, such as 401k, 403b and 457. In the past, if you were over 70 and a half years old, you would lose the ability to contribute to a traditional IRA. However, under the new law, there are no age restrictions. Nor is there any age restriction for people over 70 years of age to contribute to a 401 (k) plan or a Physical Gold IRA. For starters, custodians holding IRAs aren't required to accept contributions from savers over 70 and a half years old, according to new guidance from the IRS. Those who do so must modify their IRA contracts.

Roth IRAs are also subject to the same contribution limits as traditional IRAs: every dollar contributed to a traditional IRA reduces the amount you can contribute to a Roth IRA.