* Q3 EPS $0.40 vs estimate of $0.33
* Provision for income taxes down by $18 mln
* Shares rise 6 pct
Oct 14 (Reuters) - Progressive Corp (PGR.N), one of the largest U.S. auto insurers, posted a quarterly profit, exceeding analysts' estimates, aided in part by an improving investment environment that reduced provision for income taxes.
The company earned $269.9 million, or 40 cents a share for the third quarter, compared with a loss of $684.2 million, or $1.03 a share, a year ago.
Analysts were looking for a profit of 33 cents a share, excluding items, according to Thomson Reuters I/B/E/S.
Net premiums earned for the period rose about a percent to $3.45 billion, the company said.
Progressive's combined ratio fell 2.4 basis points to 92.7 percent. Combined ratio is the percentage of premiums an insurer has to pay out in claims and expenses. A figure over 100 indicates that underwriting was unprofitable.
Shares of the Mayfield Village, Ohio-based company were up about 6 percent at $17.40 before the bell. They closed at $16.45 Tuesday on the New York Stock Exchange. (Reporting by Anurag Kotoky in Bangalore; Editing by Maju Samuel)