The lack of an inflation adjustment almost certainly means that the cap on regular investments in the TSP will remain at $18,000 and the limit on “catch-up contribution” investments–additional investments allowed for those 50 or older in a calendar year who make the full regular investment–will remain at $6,000. The IRS has not made a formal announcement regarding those figures, but they increase only after accumulated inflation since the previous increase–there was one for 2015–has exceeded a certain level. The limits apply to the total of traditional pre-tax investments and after-tax Roth investments, for those making both types; they don’t include agency contributions on behalf of FERS-covered employees or rollovers from similar plans of prior employers.