O'Connell Oil was founded in 1925 by Ralph Maurice O'Connell. The company began with a gasoline distributorship from Amoco to which was added a distributorship with Shell and eventually Gulf Oil. R.M.O'Connell further expanded the business by including the sale of heating oil. The business steadily grew during the 1940's, 1950's and 1960's to become the largest fuel and oil dealer in Berkshire County. O'Connells continued to grow through expanding their market area and acquisitions.
The company name was changed in the 1970's from R.M. O'Connell Oil to its present name of, O'Connell Oil Associates Inc.. At this time Ralph M. O'Connell's son William R. O'Connell took over the company. In 1983 William R. O'Connell and Michael R. Sobon opened the first of thirty Convenience Plus stores, innovatively combining a mini mart with a gas station. In the years following they expanded throughout Western Massachusetts adding other oil companies and convenience stores to O'Connell Oil Associates Inc..
At the end of 2000, with the passing of William R. O'Connell, Michael R. Sobon became the owner and CEO of the company. He has continued the O'Connell Oil legacy as a leader in its field. O'Connell Oil Associates Inc. now owns and operates three oil company locations, thirty Convenience Plus Stores, seven gas stations, a wholesale gasoline business and full service commercial and residential plumbing, heating and air conditioning departments.