5 CFR 1650.6: Deceased participant.

(a) The TSP record keeper will cancel a pending TSP withdrawal request if it receives notice, in the form and manner prescribed by the TSP record keeper, that a participant is deceased. The TSP record keeper will also cancel an annuity purchase made on or after the participant's date of death but before annuity payments have begun, and the annuity vendor will return the funds to the TSP.

(b) If the TSP record keeper processes a TSP withdrawal request before being notified that a participant is deceased, the funds cannot be returned to the TSP.