UPDATE 1-Envestra H1 profit jumps on tax gain

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SYDNEY, Feb 27 (Reuters) - Envestra Ltd (ENV.AX), Australia's biggest natural gas distributor, posted a jump in half-year net profit on Wednesday, boosted by a large one-off gain.

Envestra said in a statement its net profit after tax was A$171.4 million ($160.2 million) for the six months ended Dec. 31, compared with A$1.7 million a year ago.

Profit before tax was A$28.8 million ($26.9 million) in the first half, up 32 percent from a year ago, Envestra said.

Energy retailer Origin Energy Ltd (ORG.AX) sold its 17.2 percent stake in Envestra last July to pipeline investor APA Group Ltd (APA.AX). The transfer of ownership resulted in a one-off tax benefit of A$153 million, Envestra said.

Envestra, which saw its half-year revenue rise 2 percent to A$185.4 million, said it added about 12,500 new customers to its distribution networks.

The new customers will add about A$3 million a year to future revenue, Envestra said.

Envestra, whose largest shareholders are Australia's APA Group Ltd (APA.AX) and Hong Kong's Cheung Kong Infrastructure Holdings Ltd (1038.HK), declared an interim distribution of 5.7 Australian cents.

Distribution in the second-half was forecast to be 3.8 cents per security, bringing full-year distribution to 9.5 cents, the Adelaide-based company said.

Shares in Envestra, which has assets of about A$2.5 billion, were up 5.2 percent at A$0.81 by 0236 GMT, outperforming a 1.2 percent gain in the benchmark S&P/ASX 200 index .AXJO. ($1=A$1.07) (Reporting by Fayen Wong)