5 C.F.R. § 1655.5
Loan repayment period
(a) Minimum. The minimum repayment period a participant may request for a general purpose loan is 12 months of scheduled payments. The minimum repayment period a participant may request for a residential loan is 61 months of scheduled payments.
(b) Maximum. The maximum repayment period a participant may request for a general purpose loan is 60 months of scheduled payments. The maximum repayment period a participant may request for a residential loan is 180 months years of scheduled payments.