For most of your federal career, the TSP does exactly what it is supposed to do. You contribute, your agency matches, the funds grow, and you largely leave it alone. The system is straightforward, and the costs are remarkably low. It is one of the best retirement savings vehicles available anywhere.
But retirement changes the equation. Once you separate from federal service and start taking income from your TSP, a set of rules kicks in that many federal employees have not spent much time thinking about. One in particular can limit your flexibility at exactly the moment you need it most.
It is called the pro-rata withdrawal rule, and understanding it is an important part of building a smart withdrawal strategy.
How the Rule Works
When you take a withdrawal from your TSP in retirement, you cannot choose which fund the money comes from. The TSP is required to pull your withdrawal proportionally from every fund in which you are invested. If your account is 60% in the C Fund and 40% in the G Fund, every dollar you withdraw will come out at that same 60/40 split, regardless of what the market is doing at that moment.
In practical terms, this means you cannot tell the TSP to leave your stock funds alone during a downturn and draw only from the G Fund instead. The decision is made for you.
Why This Matters
This is where sequence of returns risk comes into play. If you retire during a period of market volatility and your account is down, the pro-rata rule forces you to sell shares from your stock funds at depressed prices just to cover living expenses. Those shares cannot recover because they are gone. Combined with ongoing withdrawals, a rough stretch early in retirement can do lasting damage to a TSP balance that might otherwise have rebounded over time.
The inability to draw from a single fund or bucket means you have less control over your portfolio during the moments when control matters most.
What You Can Do About It
There are a couple of workarounds worth knowing. One option is to perform inter-fund transfers after a withdrawal, moving money from the G Fund into your stock funds to replace what was taken out. This takes discipline and attention, but it preserves your intended allocation over time.
The other option is to roll your TSP into an IRA after retirement. An IRA gives you full flexibility to draw from specific assets, which allows you to keep your stock holdings intact during downturns and pull income from more stable holdings instead.
Neither option is right for everyone, and rolling out of the TSP means leaving behind its famously low expense ratios. But understanding the limitation is the first step toward building a withdrawal strategy that accounts for it.
A Federal Retirement Consultant (FRC®) can help you weigh your options and build a plan that fits your situation.
