Only about half of private sector workers have access to an employer-sponsored retirement savings plan comparable to the TSP, GAO has said.

A report said that several studies put the number with access at just below 50 percent and that its own analysis puts the number slightly above, but either way, a substantial percentage cannot save through such plans and miss out on the tax benefits and potential for employer contributions.

“Among those not participating, the vast majority—84 percent—lacked access because they either worked for employers that did not offer programs or were not eligible for the programs that were offered, for example, because they were new employees or in specific jobs that were excluded from the program. In particular, lower-income workers and those employed by smaller firms were much less likely to have access to programs,” it said.

In contrast, the TSP is available to all federal employees immediately upon hiring.

“As workers live longer and face potential changes to future Social Security benefits, participating in a workplace retirement savings program is increasingly important to help ensure their retirement income security,” GAO said.