When a federal employee needs cash and the TSP is the only realistic source, two options appear on the table: an in-service withdrawal or a TSP loan. Both put money in your hand. Both come out of your TSP balance. They are not the same in cost, in tax treatment, or in long-term impact.

For most federal employees who need short-term liquidity, the TSP loan is the cheaper and cleaner answer. The exceptions exist, and they matter, but they are narrower than most employees realize.

What a TSP loan actually does.

A TSP loan lets you borrow from your own TSP balance, repay the loan (with interest) through payroll deduction, and continue to receive agency contributions on the unborrowed portion of your balance. The interest rate is the G Fund rate at the time the loan is issued, plus 1%. The interest you pay is credited back to your own account.

TSP loans have limits. You can have up to two outstanding loans at a time, and the total outstanding balance cannot exceed $50,000 minus your highest outstanding loan balance in the prior 12 months. The minimum loan is $1,000 and the maximum term is 5 years (15 years if the loan is used to purchase a primary residence).

What an in-service withdrawal actually does.

An in-service withdrawal is a permanent distribution from your TSP. The dollars you receive are no longer in your TSP balance and do not grow tax-deferred or tax-free going forward. Federal and state income tax applies in the year of the withdrawal. For Traditional dollars, the TSP withholds 20% federal income tax at the time of the withdrawal.

For participants under 59½, an in-service withdrawal triggers a 10% early-withdrawal penalty on top of the income tax, unless the withdrawal qualifies as a financial hardship under the TSP’s specific definition. The 10% penalty is the visible cost, but the lost compounding is the larger cost.

Side-by-side: a $20,000 example.

Assume a federal employee aged 45 with a $200,000 Traditional TSP balance needs $20,000 for a home repair that does not qualify as a casualty loss. The two options:

TSP loan option.The employee borrows $20,000 from the TSP at, say, a 5% interest rate. Payroll deduction repays the loan over 5 years. The interest paid (about $2,700 over the life of the loan) is credited back to the participant’s own TSP account. No income tax. No 10% penalty. No six-month match suspension.

In-service withdrawal option. The employee takes a $20,000 distribution. Federal tax withholding of $4,000 is taken at the source. The participant receives $16,000 and owes another $2,000 to $4,000 at tax time (depending on bracket). The 10% early withdrawal penalty adds $2,000. The six-month agency match suspension costs another several thousand in forfeited agency contributions. And the $20,000 is gone from the TSP balance forever.

The visible cost difference is several thousand dollars. The compounding cost difference, measured at age 65, is several tens of thousands of dollars. The loan is not even close.

When the withdrawal is actually better.

There are cases where the in-service withdrawal is the right answer even when a TSP loan is available:

  • The participant is already at the maximum outstanding TSP loan balance or has two outstanding loans.
  • The participant is at or near retirement and prefers to simplify the balance rather than add a payroll deduction to manage.
  • The withdrawal is part of a Roth conversion or other tax-planning strategy where the tax cost is intentional and the lost-compounding is part of the modeled plan.
  • The participant is over 59½, the withdrawal is penalty-free, and the loan-versus-withdrawal comparison is closer than it is for younger participants.

The default answer.

For federal employees under 59½ who need short-term cash and have TSP loan capacity, the default answer is the loan. The default is not always right, but it is right often enough that flipping it should require a specific reason.

The exception is the financial hardship withdrawal, which has its own qualification rules and tax treatment. The hardship withdrawal is rarely the cheapest source of cash; it is sometimes the only source. We cover that category in a separate article.