GEICO outsold Allstate in personal auto insurance premiums during the first quarter of 2013, according to a Thursday report from the Chicago Tribune that was based on SNL Financial data.

The report noted that it was first time on record that GEICO showed a larger volume of business than Allstate, which has long held the second-highest position in car insurer rankings. It’s not clear whether GEICO will remain on top, however.

But data show that in the first quarter, GEICO’s $4.72 billion in private auto premiums outpaced the $4.53 billion sold by Allstate, while Progressive wrote $3.91 billion in premiums during that period, according to the report.

State Farm has been the longtime leader in premium sales and share of the U.S. auto coverage market.

The report also found that, in the 12 months ending on March 31, Allstate and GEICO were in a tight competition for written premiums, $17.65 billion to $17.16 billion, respectively.

Figures released in April by the National Association of Insurance Commissioners (NAIC) showed just how tight that margin was. According to the NAIC, Allstate and GEICO were basically neck-and-neck with the second- and third-highest share of premiums in the U.S. auto insurance market: Allstate had 10 percent and GEICO had a little over 9.5 percent.

Progressive trailed both at about 8.3 percent, while State Farm topped all at 18.4 percent of premiums in the marketplace, according to the NAIC.

SNL Financial also said that “GEICO’s business tends to be more seasonal than Allstate’s,” which may signal Allstate reclaiming its spot for second-quarter sales, the Chicago Tribune reported.