Implementation of President Obama’s health care law is running behind schedule and it’s unclear whether federal health insurance exchanges will be up and running on time in October, according to two reports from the Government Accountability Office.

The main way Obamacare plans to expand insurance is by creating exchanges in all 50 states plus the District of Columbia, on which individuals and small businesses can use government subsidies to purchase regulated but privately administered health insurance plans. Under the law, states can choose whether to set their own exchanges, partner with the federal government, or leave the task entirely up to the federal government. All told, the federal government through the Centers for Medicare and Medicaid Services will have a role in running exchanges for individuals in 34 states and for small businesses in 33 states.

According to the timeline, the exchanges will have to be up and running on October 1st so that individuals can start to enroll before the plans begin offering benefits on Jan. 1, 2014. But doing so requires a lot of logistical hurdles. The aim is to create websites on which individuals can log in and search for plans as easily as they would purchase airline tickets on Expedia and Orbitz. At the same time, numerous government databases will have to interact with each other so that they can provide real-time verification of applicants’ income levels to make sure they are eligible to receive subsidies to purchase insurance and then to calculate those subsidies.

“Much progress has been made, but much remains to be accomplished within a relatively short amount of time,” the GAO concluded in its report. “CMS’s timelines provide a roadmap to completion; however, factors such as the still-evolving scope of CMS’s required activities in each state and the many activities yet to be performed — some close to the start of enrollment — suggest a potential for challenges going forward. And while the missed interim deadlines may not affect implementation, additional missed deadlines closer to the start of enrollment could do so. CMS recently completed risk assessments and plans for mitigating risks associated with the data hub, and is also working on strategies to address state preparedness contingencies. Whether these efforts will assure the timely and smooth implementation of the exchanges by October 2013 cannot yet be determined.”

The GAO reached a similar conclusion in a separate report on small business exchanges.

In response to the report, the Department of Health and Human Services reiterated that it was confident the exchanges will be ready by Oct. 1.