- 1919: After emigrating to the United States from Russia, Irving Sippin moves to Monroe Connecticut, and begins to sell coal to surrounding homes and farms.
- 1929: Customers continue to come on board, kerosene and gasoline are added as additional products.
- 1939: Eldest son Maxwell and second eldest son Victor begin work in the coal and fuel business.
- 1940: Maxwell is drafted into the Army, Victor joins the Navy and serves on a PT boat squadron
- 1944: Victor Sippin is killed in action in southern France after his PT boat was struck by a German mine shortly after the D-day invasion.
- 1945: Youngest son Bernard joins the company and assists in delivering fuel and coal.
- 1953: Maxwell and Bernard open up first location on Main Street selling gasoline, automotive services and heating fuel.
- 1953: Sippin Bros. Oil Company Inc. corporation was formed
- 1958: Sippin Brothers Oil Company erects building on its current location site at 234 Main St., Monroe
- 1960: First bulk plant facility is erected consisting of several 30,000 gallon saddle tanks
- 1964: Second bulk plant storage tank is erected, consisting of a new vertical 250,000 gallon tank in a modern loading rack facility.
- 1966: Bernard establishes Stepney Motors, a full-service automotive company that provides repairs, bodywork, auto towing.
- 1967: Sippin expands its tire business, erecting a large tire warehouse
- 1968: Founder Irving Sippin passes away
- 1971: Sippin Tire business sold
- 1972: Sippin family enters into the motorcycle business, acquiring a Suzuki franchise, followed by Honda, BMW, Yamaha and Kawasaki. Sippin continues in the motorcycle business growing to be one of the largest motorcycle companies in the state of Connecticut.
- 1974: Bernard buys out brother Maxwell and assumes 100% ownership of company.
- 1975: Third-generation members David, Mark, and Gary begin to work at the company
- 1978: Sippin family begins to aggressively invest in real estate in a local community, establishing Sippin commercial properties. Investments include retail shopping centers, commercial and industrial facilities, and office buildings.
- 1981: Sidco distributing is established which is a regional distribution company founded by Gary Sippin which provided a variety of products including space heaters and humidifiers. Customers were served throughout New England with these products
- 1985: Gary Sippin joins oil business, Sippin Brothers Oil Company is renamed Sippin Energy Products
- 1986: Dave Sippin takes over responsibilities over Sippin Commercial real estate and continues to build and invest in commercial properties.
- 1987: Mark Sippin joins Sippin Commercial Properties providing office and tenant management.
- 2002: The Sippin family are awarded 1st place for the Nosco family business award by the University of Connecticut
- 2002: Gary Sippin receives the CEMA (Connecticut Energy marketers Association), marketer of the year award.
- 2009: Gary Sippin co-founds Destwin Energy Systems, a software development company established to provide e-commerce and risk management solutions for energy marketers throughout the United States.
- 2010: Gary Sippin receives CEMA associate energy marketer of the year award for work in energy risk management software.
- 2011: Sippin Energy Products receives the Better Business Bureau’s National torch award for business ethics.
- 2013: Bernard Sippin receives Monroe citizen of the year award.
- 2015: Sippin Energy Products receives the Monroe business of the year award.
- 2016: Sippin Energy enters into the propane business.
- 2019: Sippin Energy Products and the Sippin family celebrate 100 years of business.
- 2020: Eric Sippin graduates from Sacred Heart University with MBA and joins company as 4th generation family member.