For 2015, the maximum contribution amount for a 401(k) is $18,000, and the contribution limit for all IRAs, traditional and Roth, is $5,500, according to Betterment. For people over 50, the contribution limit for a 401(k) is $24,000 and $6,500 total for all IRAs in 2015.
However, contribution limits are subject to additional restrictions; an individual cannot contribute more than his taxable compensation for the year into an IRA, according to the IRS. Also, for Roth IRAs, if an individual's modified adjusted gross income is higher than $183,000 and he is married filing jointly, he cannot contribute the maximum amount to a Roth IRA but instead can contribute a reduced amount. If modified AGI is above $116,000 for a person filing as single, head of household or married filing separately, a reduced amount can be contributed. Once modified AGI is above $193,000 for married individuals filing jointly and above $131,000 for individuals filing as single, head of household or married filing separately for 2015, no money can be contributed to a Roth IRA. People who file as married filing separately but have lived with their spouses for part of the year have a limit of only $10,000 as of 2015.