Active employees who are age 50 or above, or who will be before the end of the year, and who wish to make “catch-up contribution” investments into the TSP must make an election to do so, even if they made such investments last year. Unlike regular TSP investments, those don’t carry over from year to year. Catch-ups are allowed if an eligible individual has hit the annual dollar TSP limit ($18,000 this year) or is on an investing pace to do so by the end of the year. The maximum allowable catch-up is $6,000 this year. The investments must be made from payroll withholding. Those wishing to space out such investments over the rest of the year should check with their payroll offices to see how many pay distribution dates will remain in the year by the time their election take effect.