Officials tell the Los Angeles Times the site received 645,000 hits onTuesday, well below the 5 million they initially reported.
Covered California spokesman Dana Howard said the error occurred because someone misspoke and thought the site had in fact received 5 million hits.
The figure was cited by California officials as an indicator of the high level of interest in the exchange. They also blamed it for some of the problems with the system.
The enrollment portion of the exchange website was taken offline from Tuesday night until late Wednesday morning.