U.S. consumers may have no idea how much retirees really spend on health care costs not covered by Medicare.

Analysts at Voya Financial raise that possibility in a summary of results from a recent telephone survey of 1,003 U.S. adults ages 18 and older.

Another financial services firm, Fidelity Investments, produces a well-publicized series of annual estimates of what a 65-year-old couple retiring during the estimate year can expect to spend on hospital care, outpatient services, physician services, prescription drugs, and related products and services over the course of retirement.

Fidelity estimated in August that the typical couple retiring in 2016 would need about $260,000 to cover post-retirement out-of-pocket health care costs, or about $130,000 per person. The estimate includes only acute health care expenses, not long-term care costs.

Only 19% of the Voya survey participants said they thought they would spend more than $100,000 on post-retirement health care costs, and 31% said they expected to spend $25,000 or less.

Some of those consumers might have given low estimates because they expect to be poor enough to qualify for Medicaid, the health program for the poor. But survey participants who said they had household income of $100,000 or more also gave what appear to be low post-retirement health care spending estimates.

Only 35% of the high-income participants said they expect to spend $150,000 or more on health care after they retire.

Consumers who said they had tried to estimate how much they would spend on post-retirement health care costs gave bigger estimates. About 25% said they thought they would spend more than $100,000.

Only about 2% said they think annuities or life insurance policies designed to produce retirement income will be their main source of cash for paying post-retirement health care bills.

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