Marcus retired from the Social Security Administration at 56 with $610,000 in his TSP. Within a week, three brokerage firms had called him. One mailed a glossy folder. Each promised "more flexibility" if he rolled the money into an IRA. Marcus had one question: Is any of that true?

Partly. A rollover can be a smart move, but it can also quietly cost you tax-free access to your own money. The difference comes down to a few details most pitches skip.

What a rollover actually does

Once you separate from federal service, you can move your TSP balance to a traditional IRA, a Roth IRA, or another eligible employer plan. You can move all of it or part of it.

The tax treatment depends on the match:

  • Traditional TSP to traditional IRA: no tax when you move it. You pay ordinary income tax when you withdraw later.
  • Roth TSP to Roth IRA: no tax, provided the money moves as a direct transfer.
  • Traditional TSP to Roth IRA: this is a conversion. The full amount moved is taxable income that year.

Always request a direct transfer, where the TSP sends the money to the IRA custodian. If a check is made out to you instead, the TSP must withhold 20 percent for federal tax. You then have 60 days to deposit the full amount, including the 20 percent you never received, or the shortfall counts as a taxable distribution. Direct transfers avoid the problem entirely.

The age 55 trap

This is the detail that matters most for people who retire in their mid-50s.

If you separate from service in or after the year you turn 55 (50 for certain public safety roles), you can withdraw from the TSP without the 10 percent early withdrawal penalty. Ordinary income tax still applies on traditional dollars, but the penalty does not.

Move that money to an IRA and the exception disappears. IRA withdrawals before age 59½ generally face the 10 percent penalty unless another exception applies.

Say Marcus needs $25,000 a year to bridge the gap until his pension and Social Security fully cover his costs. If he rolls everything into an IRA, those withdrawals could carry a $2,500 penalty each year. If he leaves enough in the TSP to cover the bridge years, he pays none.

The workable answer is often a split. Keep a few years of spending money in the TSP and roll the rest. Confirm the current rules and your own eligibility at tsp.gov and irs.gov before you act, because the details matter.

Where an IRA can beat the TSP

The TSP is a good plan, so the case for leaving has to be specific. These are the real advantages of an IRA:

  • Investment choice. The TSP offers the G, F, C, S, and I Funds plus the lifecycle funds. An IRA opens up individual stocks, bonds, ETFs, and annuities. Whether you need that is another question.
  • Withdrawal control. The TSP has improved its withdrawal rules, but an IRA still allows more flexible timing and amounts.
  • Roth conversions in small slices. In an IRA, you can convert exactly the amount that fills a tax bracket, year after year.
  • Estate planning. Some people prefer the beneficiary options and account structure an IRA offers.

Where the TSP wins

Costs first. TSP fund expenses run a few hundredths of a percent, and the exact figures are published at tsp.gov each year. A typical managed IRA portfolio can cost ten or twenty times that. On $600,000, a one percent annual fee is $6,000 a year. Over 25 years, that adds up to a serious sum.

The G Fund is the other piece. It pays a rate tied to Treasury securities with no principal risk, and an IRA has no real equivalent. For retirees who want a stable bucket for the early years, that matters.

The TSP is also easy to understand. One account, a handful of funds, and no one trying to sell you a product with a commission.

The Roth conversion window

The best reason to roll over is often tax planning, not investing.

The years between retirement and the start of required minimum distributions can be unusually low-income years. Picture Dana, 58, retired from the Forest Service. Her FERS pension is $42,000. She is not yet claiming Social Security. After the standard deduction, a good chunk of the lower tax brackets sits empty.

She could convert $30,000 of traditional money to a Roth IRA each year, paying tax at the lower brackets now. This shrinks the traditional balance that will be forced out later at potentially higher rates, and it builds tax-free money for her heirs or for a rainy day.

A few cautions apply:

  • Pay the conversion tax from outside savings if possible. Paying from the converted money shrinks the benefit.
  • Watch the knock-on effects. A big conversion can raise Medicare premiums two years later and make more of your Social Security taxable.
  • Bracket thresholds change every year. Check irs.gov for current numbers.

The pro rata wrinkle

If you do backdoor Roth contributions, a large pre-tax IRA balance can make them partly taxable under the pro rata rule. The TSP accepts rollovers from traditional IRAs, so in some cases you can move IRA money back into the TSP to keep it out of that calculation. That is a niche situation, but worth knowing.

A few other things to weigh

TSP loans are only available while you are employed, so rolling out does not cost you anything there, but rolling out does end any future chance of borrowing if you return to federal service. Creditor protection also differs. TSP assets have strong federal protection, while IRA protection varies by state outside of bankruptcy.

Required minimum distributions deserve a look as well. Under current law they start at 73 for many people, and at 75 for those born in 1960 or later. Roth balances in the TSP no longer require distributions during your lifetime under recent rule changes, but confirm the current treatment at tsp.gov.

A sensible way to decide

Before you sign anything, work through these steps:

  1. List your bridge-year spending needs and keep that amount in the TSP if you are under 59½ and eligible for the age 55 exception.
  2. Compare total costs. Get the IRA's all-in fees in writing, including fund expenses and advisory fees.
  3. Estimate your tax brackets for the next ten years to see whether conversions make sense.
  4. Move in stages. Nothing forces you to decide on your last day of work. The TSP will hold your account.

Marcus ended up leaving $90,000 in the TSP to cover his bridge years and rolled $520,000 into a low-cost IRA, where he plans modest annual Roth conversions. The brokerage folder went in the recycling bin.

Your answer may look different, and that is fine. What matters is that the rollover is a decision you make on purpose, with the penalty rules and the fee math in front of you. A tax professional who knows federal benefits can check the numbers before you commit.