This Kaiser Family Foundation brief explains the key components of the Congressional Budget Office's estimates of the Affordable Health Care for America Act (H.R. 3962) and the Patient Protection and Affordable Care Act (H.R. 3590).

From the brief:

The federal cost of the various health reform plans has emerged as one of the most visible focal points in the debate. In his speech on health care to a joint session of Congress, President Obama said that a health reform plan would cost the federal government about $900 billion over 10 years, a statement widely interpreted as setting a ceiling on the budgetary cost of reform. There are any number of ways to tally up the cost of one of the current health reform plans, since they not only expand coverage but also have significant effects on existing government health programs such as Medicare and Medicaid, as well as on tax revenues. However, the generally accepted definition in the context of the current debate centers around the cost of expanding health coverage, which can be measured on both a gross and net basis (as shown in Table 2, which shows costs as presented by CBO). CBO treats improvements in Medicare and Medicaid that increase costs as part of the net overall change in spending for current federal programs.

Full brief available at: Assessing CBO Estimates of the Cost and Coverage Implications of Health Reform Proposals (PDF | 513.59 KB)

Kaiser Family Foundation. (2009). Assessing Congressional Budget Office estimates of the cost and coverage implications of health reform proposals.