UPDATE 1-Envestra H1 profit jumps on tax gain

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SYDNEY, Feb 27 (Reuters) - Envestra Ltd (ENV.AX: Quote, Profile, Research, Stock Buzz), 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: Quote, Profile, Research, Stock Buzz) sold its 17.2 percent stake in Envestra last July to pipeline investor APA Group Ltd (APA.AX: Quote, Profile, Research, Stock Buzz). 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: Quote, Profile, Research, Stock Buzz) and Hong Kong's Cheung Kong Infrastructure Holdings Ltd (1038.HK: Quote, Profile, Research, Stock Buzz), 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 . ($1=A$1.07) (Reporting by Fayen Wong)