States that need to overhaul their computer systems to handle the changes in Medicaid enrollment under the Patient Protection and Affordable Care Act (PPACA) will have 90% of the cost paid by the federal government, according to a new rule published by the Centers for Medicare and Medicaid Services (CMS).

While PPACA will simplify the rules for determining Medicaid eligibility and the process for enrolling people, most states likely will need significant system upgrades to accommodate the new and expanded availability of health care to millions of currently uninsured Americans. If they are to receive the enhanced funding, states must meet certain performance standards not only for the determination system but for seamless coordination with the new health care insurance exchanges. The 90% match (up from the previous 50%) will be available through December 31, 2015, after which it will drop to 75%.

The final regulation, CMS-2346-F, will be published in the Federal Register next week.