Feb 8 (Reuters) - Australia's AGL Energy posted a fourfold jump in first-half underlying profit on Thursday, helped by higher wholesale electricity pricing and improved market conditions.

The energy supplier said profit after tax attributable for the six months ended Dec. 31 was A$399 million ($260.11 million), compared with A$87 million a year earlier.

According to Jefferies, the consensus estimate was of A$311 million.

($1 = 1.5340 Australian dollars) (Reporting by Poonam Behura and Shivangi Lahiri in Bengaluru; Editing by Shilpi Majumdar)