1925 - Mississippi Power was established at midnight on January 1, 1925, when it took over the assets of the Gulfport and Mississippi Coast Traction Company, which operated a small generating plant in Gulfport and an electric railway from Pass Christian to Biloxi. Initially, the company offered limited electric service to about 5,500 customers along the Coast.
1929 - The company extends from Tennessee to the Coast with 40,000 customers. During the early years of the company, electricity was transmitted to eastern Mississippi from hydroelectric facilities in Alabama.
1934 - The Tennessee Valley Authority takes over northern half of Mississippi Power Company's service area. That sale reduced the company's service area to the 23 southeastern counties of Mississippi, the area it continues to serve today.
1940 - The Security and Exchange Commission orders dissolution of Commonwealth & Southern, a predecessor to Mississippi Power Company's parent corporation, Southern Company.
1945 - Following years of difficulties connected with the Depression as well as material restrictions and manpower shortages during World War II, Mississippi Power’s first power plant begins commercial operation near Hattiesburg. Plant Eaton is named for the company's first president, Barney Eaton.
1947 - Southern Company established as the holding company for four utilities including Mississippi Power.
1951 - Mississippi Power's second generating plant, located near Meridian, begins producing electricity. Plant Sweatt is named for the company's second president, Lonnie P. Sweatt.
1953 - A second unit at Plant Sweatt increases electricity generation to 1 billion kilowatt-hours a year.
1956 - Mississippi Public Service Commission established.
1957 - Plant Watson begins commercial operation. The facility is named for the company's third president, Jack Watson.
1962 - In partnership with one of its sister companies, Alabama Power, Mississippi Power begins construction of a generating plant along the Warrior River near Demopolis, Alabama. Today, Mississippi Power owns 40 percent of the 200-megawatt Greene County Generating Plant.
1965 - Unit Four built at Plant Watson.
1970 - Mississippi Power receives its first Edison Award in recognition for service restoration following Hurricane Camille in 1969.
1977 - The first unit of Plant Daniel in Jackson County begins commercial operation. The plant is named after the company’s fourth president, Victor J. Daniel.
1981 - Unit Two at Plant Daniel begins commercial operation.
1983 - Company begins annual $25,000 donation to the Red Cross to aid the elderly disadvantaged with heating bills. The company later raised the annual donation to $50,000.
1986 - Performance Evaluation Plan enacted, the nation's first performance-based rate making plan for an electric utility.
1992 - Environmental Compliance Overview Plan enacted.
1995 - Nine new summer peak demands set from 1,881,000 kW to 2,095,000 kW.
1998 - Six new summer peak demand records set, culminating in 2,339,000 kW.
1999 - Four new summer peak demand records set, the highest being 2,439,000 kW.
1999 - Construction begins on two combined-cycle gas-fired generating units at Plant Daniel that would increase the company's generating capacity by nearly 50 percent and offer the era’s latest technology for efficiency and environmental protection.
1999 - Mississippi Power joins other companies in preparing for the Y2K bug that threatens to shut down computers and other critical operations when the year turns from 1999 to 2000. Midnight doesn't cause a blip in electric operations - or anything else for that matter.
2002 - Duke Energy, a large-scale independent power producer, interconnected with Mississippi Power's transmission system with station service provided at its 640-megawatt plant in Enterprise.
2003 - Mississippi Power Education Foundation started its New Teacher Assistance Grants designed to attract and retain high quality teachers to service area schools. The program provides $750 grants to help first-year teachers set up classrooms.
2003 - The Mississippi Power Community Connection was created, combining the charitable efforts of employees, retirees and their families with matching funds to boost the amount of charitable donations to community organizations and/or provide employees in need with assistance.
2003 - Mississippi Power establishes a "green rate" for customers, an optional rate to contribute to the production or purchase of renewable energy - electrical energy produced using renewable resources.
2005 - Hurricane Katrina struck on August 29, taking down the company's electric system and leaving every single customer without service. A team of 12,000 - employees and crews from 23 states - restore service to all who can receive it in only 12 days. For its efforts after Katrina, Mississippi Power was presented its second Edison Award.
2006 - Plant Daniel in Escatawpa, Miss., is selected for a multi-year research project to test carbon dioxide storage by the U.S. Department of Energy and the National Energy Technology Laboratory.
2006 - The Public Service Commission approves the company's plan to build a new Storm Center further inland and allowed the company to increase its storm reserve to $60 million.
2007 - The company's headquarters building, severely damaged during Hurricane Katrina, is officially rededicated, with the city's mayor recalling Mississippi Power President Anthony Topazi saying that the company would "come back better than ever, with a better presence in downtown Gulfport." On the second anniversary of Hurricane Katrina, Mississippi Power unveiled the commemorative sculpture, Forward, which is located on the plaza at its headquarters.
2007 - Mississippi Power announces a three-year total commitment to Mississippi State University's Early Childhood Education Institute. It also endows a professorship in electrical and computer engineering with a $500,000 commitment.
2007 - Mississippi Power teams with the Mississippi Department of Wildlife and Fisheries to begin restocking the Pascagoula River after Hurricane Katrina's massive fish kill by releasing more than 2,500 largemouth bass advanced fingerlings.
2011 - Mississippi Power storm teams went to assist the utilities in Maryland and Washington D.C. in August following Hurricane Irene and returned to the east coast in November after a winter snow storm left more than 604,000 New Jersey utility customers without power.
2012 - Mississippi Power crews assisted Entergy Arkansas restore outages after an extreme winter storm crossed the nation through the December holiday season.
2012 - The company's expertly maintained infrastructure provided the necessary strength to withstand the full force of an extremely slow-moving Hurricane Isaac. With only a little more than 18,000 outages at the peak of the storm, crews aggressively worked to restore service to all customers less than 36 hours later.
2014 - In August, Plant Ratcliffe begins generating electricity from natural gas, delivering value to customers.
2017 - Mississippi Power becomes the state's largest partner in renewable energy with the dedication of three large-scale solar facilities, providing more than 105 MW and powering nearly 15,000 homes. A fourth project is approved that will provide 53 MW and power 8,000 homes.