UPDATE 2-Polish PGNiG Q3 net doubles, beats expectations

* Q3 net profit more than doubles to 406 mln zlotys

* Beats market forecasts of 351 mln zlotys

(Adds analyst quote, details)

WARSAW, Nov 12 (Reuters) - Polish gas monopoly PGNiG PGNI.WA reported better-than-expected third-quarter net profit on Thursday, which more than doubled thanks to improved margins on gas imported from Russia.

The group earned 406 million zlotys ($146 million) versus 351 million seen by analysts polled by Reuters. In the year-ago period it had a net profit of 179 million zlotys.

The state-controlled monopoly, which in the first half of the year reported a 493 million zloty net loss, posted its first net profit since the third quarter of 2008 and made a step towards its goal of making a net profit for the full year.

"The strengthening of PGNiG's financial position was caused mainly by better profitability of gas sales," the company said in its statement. "The growth ... took place mainly as a result of the fall of unit costs of imported gas by 29 percent."

PGNiG, which imports about two-thirds of the gas it sells from Russia, lost money on imports in the previous quarters because it cost more than the price that state energy regulator URE allows it to charge to customers.

The company's operating profit also came in above expectations at 495 million zlotys, 2.5 times more than a year earlier and compared to 417 million seen in analyst poll.