In order to invest in a 401(k) account, you must ask your employer to deduct a certain amount of money from your paycheck to pay into it. Whatever your employer deducts to invest into the 401(k) is not subject to taxation as income from the IRS. These funds and the interest that they generate remain untaxed until dispersal.
In the United States, the general minimum age limit for employment is 14. Because of this, employees may make contributions into 401(k) plans from this age. However, the federal government does not legally require employers to include employees in their 401(k) programs unless they are at least 21 years of age. If you are at least 21 and have been working for your employer for at least one year, your employer must allow you to participate in the company's 401(k) program.
Employers cannot deny anyone the right to participate in a 401(k) plan on the basis of maximum age. As long as individuals are working and receiving income from an employer, they may pay into the 401(k) plan provided by the employer, with no cutoff age.
While the IRS does not tax the contributions that you make into a 401(k) plan, it does tax the distributions of that plan. You may receive normal distributions from your plan once you have reached the age of 59 1/2 or if you are in a state of hardship, such as disability or unemployment. If you make withdrawals from your account outside of these conditions, you will incur additional tax penalties.