Unitil Contracts with Mirant for Electric Supply in New Hampshire

Hampton, NH - March 17, 2003 - Unitil Corporation (AMEX:UTL) www.unitil.com announced today that the New Hampshire Public Utilities Commission has granted approval to its proposed contract with Mirant for the acquisition of Transition and Default Service and the sale of Unitil's existing power supply portfolio. This approval concludes Unitil's New Hampshire Electric Restructuring process. The revised supply arrangements will be effective on May 1, 2003, and Customer Choice will be implemented for Unitil's New Hampshire customers.

"The contract with Mirant is the result of a very competitive RFP process which fully tested the market for both the sale of our existing supply portfolio and the acquisition of Transition and Default Service for our customers," said Mark H. Collin, Unitil's Senior Vice President and Chief Financial Officer. "This is a very good deal for our customers in a challenging market, and will complete Unitil's transition to a fully restructured customer choice environment while providing for 100% recovery of stranded costs."

Under the revised supply arrangements, overall electric rates for Unitil's New Hampshire customers will rise on May 1, 2003, reflecting final, approved rates for the Stranded Cost Charge, External Delivery Charge and Transition Supply Charges. Under the new rates, a residential customer using 500 kWh per month will pay $54.99 per month, an increase of $2.47 or 4.7% compared to a monthly bill of $52.52 under current rates. These rates remain among the lowest in New England.

Transition Service energy supply will be available for three years for residential and small commercial customers beginning at a rate of $0.05148 per kWh, increasing to an expected $0.05316 on May 1, 2004, and $0.05652 on May 1, 2005. Transition Service energy supply will be available for two years for large commercial and industrial customers, those who do not choose a competitive supply option, beginning at a rate of $0.05236 per kWh, increasing to $0.05407 on May 1, 2004.

Visit Mirant's website at: www@mirant.com

Unitil is a public utility holding company with subsidiaries providing electric service in New Hampshire, electric and gas service in Massachusetts and energy services throughout the Northeast. Its subsidiaries include, Fitchburg Gas and Electric Light Company, Unitil Energy Systems, Inc., Unitil Power Corp., Unitil Realty Corp., Unitil Service Corp. and its unregulated business unit Unitil Resources, Inc. Usource L.L.C. is a subsidiary of Unitil Resources, Inc. The Usource product line of Internet-based energy brokering and related products and services is available at www.usourceonline.com.

For more information, visit Unitil at www.unitil.com or call Stephanye Schuyler at 603-773-6465.

Contact
Stephanye Schuyler
schuyler@unitil.com