INQUIRY 20-09, Spillover Method for Catch-Up Contributions to the Thrift Savings Plan (TSP)

Published: December 16, 2020
Effective: Pay Period 26, 2020


The Federal Retirement Thrift Investment Board (FRTIB), the Agency that administers the Thrift Savings Plan (TSP), will switch to the spillover method for catch-up contributions beginning with the first pay period of tax year 2021. For the National Finance Center’s (NFC) purposes, this will be effective Pay Period (PP) 26, 2020. Catch-up contributions apply to all participants age 50 and older.

The spillover method will streamline the catch-up contribution process for eligible participants. Currently, the TSP catch-up contribution program requires participants to submit Form TSP-1-C, Contribution Catch-Up Election, each year and certify that they will meet the annual Internal Revenue Code (IRC) 402(g) elective deferral limit (EDL). With this change, participants turning 50 or older in the current year will no longer need to make a separate catch-up election. Once participants reach the EDL, their regular contributions will automatically start counting toward the catch-up contribution limit. Contributions spilling over toward the catch-up limit will be matched, but only up to the 5% of salary to which participants are already entitled. TSP will discontinue Form TSP-1-C. Contributions toward the EDL and the catch-up limit will be submitted using Form TSP-1, Election Form.

Note: This will not cause any changes for tax reporting, as all TSP contributions are combined on the participant’s IRS Form W-2, Wage and Tax Statement.

Affected Systems


System Impact

Employee Personal Page (EPP)

Removed the Self-Service selection from the Thrift Savings Plan Catch-Up (Federal and Non-Federal) page.


The Thrift Savings Plan Catch-Up (Federal and Non-Federal) page in EPP will be modified as follows:


The procedure manual for this application, which is available online at the NFC Web site, is being updated to include the information in this bulletin. To view this procedure, select HR and Payroll Clients from the MyNFC drop-down menu on the NFC Home page. At the HR and Payroll Clients page, select the Publications tab and select the applicable category to access the procedure manual within the category.

For more information on the spillover method for catch-up contributions to TSP, see


For questions about NFC processing, authorized Servicing Personnel Office representatives should contact the NFC Contact Center at 1-855-NFC-4GOV (1-855-632-4468) or via the customer service portal.