The United States could have 23 million uninsured residents in 2019, even if health reform takes effect and works as hoped, according to the in-house actuaries at the Centers for Medicare and Medicaid Services.

About 5 million of the uninsured people would be undocumented aliens, but 18 million would be people who would simply chooe not to be insured, CMS Chief Actuary Richard Foster writes in a memorandum.

Some of the uninsured people would be workers who refused employer-sponsored group coverage, but most would be healthy people in the individual market who would rather pay a relatively low penalty to avoid paying more for health coverage, Foster writes.

The CMS Office of the Actuary analysis is based on the version of H.R. 3200, the America’s Affordable Health Choices Act of 2009 bill, that was reported by the House Ways and Means Committee.

Other CMS Office of the Actuary predictions:

- Although the United States would still have 23 million uninsured people in 2019 if H.R. 3200 worked as expected, the country probably would have about 57 million uninsured people in 2019 if current laws stay in effect.

- The number of people with employer-sponsored health coverage would be 169 million in an H.R. 3200 world, and 166 million in a current-law world.

- The number of people with individual health coverage or National Health Insurance Exchange coverage would be 38 million in an H.R. 3200 world, and 26 million in a current-law world.

- Enrollment in Medicare, Medicaid and the Children’s Health Insurance Plan programs would be about the same in both systems.

In the group health market, for example, employers probably would add 15 million employees and dependents to group plans, but “some smaller employers would be inclined to terminate their existing coverage, and companies with low average salaries might find it to their–and their employees’–advantage to end their plans, thereby allowing their workers to qualify for heavily subsidized coverage through the Exchange,” Foster writes.

The H.R. 3200 system probably would crowd about 12 million enrollees out of employer-sponsored group plans, and that means the net effect of H.R. 3200 might be just a 3 million increase in group plan enrollment, Foster writes.

Total ownership of individual health coverage is expected to be much higher, and about 13 million of the uninsured people who would get coverage would get it through the Exchange system, Foster writes.

“Another 14 million, who currently have individual health insurance policies, are also expected to switch to Exchange plans,” Foster writes.

Foster warns against putting too much faith in the forecasts.

H.R. 3200 “would result in numerous changes in the way that health care insurance is provided and paid for in the U.S., and the scope and magnitude of these changes are such that few precedents exist for use in estimation,” Foster writes. “Consequently, the estimates presented here are subject to a substantially greater degree of uncertainty than is usually the case with more routine health care proposals.