TUCSON, Ariz. -- UniSource Energy Corp. (NYSE: UNS) announced Dec. 29 that on Jan. 12, 2012, it will redeem $35,000,000 in principal amount of its 4.50% convertible senior notes due 2035 with CUSIP numbers 909205 AB 2 and 909205 AA 4.

The notes were originally issued in March 2005 in an aggregate principal amount of $150,000,000, all of which remain outstanding. As described below, holders of the notes selected for redemption have the option of converting their notes into shares of UniSource Energy common stock before the date specified for redemption.

The notes will be redeemed at a redemption price of 100 percent of the principal amount thereof plus accrued and unpaid interest to, but not including, the redemption date. The notes to be redeemed will be selected in accordance with the applicable procedures of the Depository Trust Co., the registered holder of the notes, for partial redemptions.

Holders of portions of the notes selected for redemption who wish to convert such portion of their notes into shares of UniSource Energy’s common stock rather than have their interests redeemed must exercise their conversion rights in accordance with the applicable procedures of DTC so as to cause the Notes otherwise subject to redemption to be surrendered for conversion prior to 5 p.m., New York City time, on the business day immediately preceding the redemption date. The notes are convertible by the holders thereof into shares of UniSource Energy common stock at a current conversion rate of 28.814 shares of common stock for each $1,000 principal amount of notes converted, which represents a conversion price of approximately $34.71 per share of common stock.

Copies of the notice of redemption may be obtained from the Bank of New York Mellon, the trustee, paying agent and conversion agent for the notes, by calling Bondholder Relations at 800-254-2826.

UniSource Energy is a Tucson, Arizona-based company with consolidated assets of approximately $3.9 billion. UniSource Energy's primary subsidiaries include Tucson Electric Power, which serves more than 402,000 customers in southern Arizona; and UniSource Energy Services, provider of natural gas and electric service for about 237,000 customers in northern and southern Arizona. For more information about UniSource Energy and its subsidiaries, visit uns.com.