Individuals who are age 50 or over at the end of the calendar year can make annual catch-up contributions.
Catch-up contributions up to $6,000 in 2015 - 2018 may be permitted by these plans:
Elective deferrals are not treated as catch-up contributions until they exceed the limit of $18,500 in 2018 ($18,000 in 2015 - 2017) or the ADP test limit of section 401(k)(3) or the plan limit (if any).
A participant can make catch-up contributions for a year up to the lesser of the following amounts:
The catch-up contribution dollar limit, or
The excess of the participant's compensation over the elective deferral contributions that are not catch-up contributions.
Plan participants must make catch-up contributions to a retirement plan via elective deferrals. Catch-up contributions must be made before the end of the plan year.
SIMPLE Plan Catch-Up Amounts
A SIMPLE IRA or a SIMPLE 401(k) plan may permit catch-up contributions up to $3,000 in 2015 - 2018. Salary reduction contributions in a SIMPLE IRA plan are not treated as catch-up contributions until they exceed $12,500 in 2015 - 2018.
403(b) Plan Catch-Up Amounts
Employees with at least 15 years of service may be eligible to make additional contributions to a 403(b) plan in addition to the regular catch-up for participants who are age 50 or over. See the discussion of 403(b) Contribution Limits for details.
IRA Catch-Up Amounts
You can make catch-up contributions to your traditional or Roth IRA up to $1,000 in 2015 - 2018. Catch-up contributions to an IRA are due by the due date of your tax return (not including extensions).