UPDATE: UIL Holdings Announces Proposed Offering of Common Stock

UIL Holdings Corporation (UIL) announced today it intends to offer approximately 5,000,000 shares of its common stock in a registered public offering. In addition, UIL expects to grant the underwriters an option for a period of 30 days to purchase up to 750,000 additional shares of the Company's common stock. The Company intends to use the net proceeds from this offering to repay short-term debt and for general corporate purposes. J.P. Morgan, BofA Merrill Lynch and Wells Fargo Securities are acting as joint book-running managers of the offering. Copies of the prospectus and prospectus supplement relating to the shares of common stock offered in this offering may be obtained by contacting J.P. Morgan at 1155 Long Island Avenue, Edgewood, NY 11717, Attn: Broadridge Financial Solutions, or by calling toll free 1-866-803-9204; BofA Merrill Lynch at 222 Broadway, New York, NY 10038, Attn: Prospectus Department, or by e-mail at dg.prospectus_requests@baml.com; or Wells Fargo Securities at 375 Park Avenue, New York, NY 10152, Attn: Equity Syndicate Dept., by calling toll free 1-800-326-5897, or by e-mail at cmclientsupport@wellsfargo.com. A shelf registration statement relating to the securities in this offering has been filed with the Securities and Exchange Commission and has become effective. This press release does not constitute an offer to sell or the solicitation of an offer to buy any securities in any jurisdiction to any person to whom it is unlawful to make an offer, solicitation or sale in such jurisdiction. The offering of these securities will be made only by means of the prospectus supplement and accompanying prospectus. Headquartered in New Haven, Connecticut, UIL Holdings Corporation

is a diversified energy delivery company serving a total of approximately 700,000 electric and natural gas utility customers in 66 communities across two states, with combined total assets of over $4 billion. UIL Holdings is the parent company for The United Illuminating Company (UI), Connecticut Natural Gas Corporation (CNG), The Southern Connecticut Gas Company (SCG), and The Berkshire Gas Company (Berkshire), each more than 100 years old. UI provides for the transmission and delivery of electricity and other energy related services for Connecticut's Greater New Haven and Bridgeport areas. SCG and CNG are natural gas distribution companies that serve customers in Connecticut, while Berkshire serves natural gas customers in western Massachusetts. UIL Holdings employs more than 1,850 people in the New England region.