June 6, 1949 – Company organized at 5115 Washington Street , West Roxbury, with 1947 Ward LaFrance, Type 120T, 1000gpm pumper, Serial # 47-2275, Shop # 118 , and a 1930 American LaFrance, Type 212, Hose & Booster Wagon, Serial # 7239, Shop # 383.
July 26, 1955 – Company changed from Double-unit to Single-unit operation.
1968 – Company received a 1964 Ward LaFrance, Model P90, 1250gpm pumper, Serial # 64-9012, Shop # 135.
1973 – Company received a 1970 Hahn 1250gpm pumper, Serial # C12-34, Shop # 127.
1973 – Fire Fighter Frank E. Williams, Engine Company 55, was awarded the John E. Fitzgerald Medal for the Most Meritorious Act of 1973, for has actions on Grove Street, West Roxbury on September 28, 1973.
Citation for Fire Fighter Frank E. Williams.
November 10, 1984 – Company received a new 1984 Sutphen 1500gpm pumper, Serial # HS-1854, Shop # 191.
1986 – Brush Unit #2 was established, as a section of Engine 55. Brush Unit #2 was assigned a remodeled 1981 GMC/Sutphen, Serial # HS-1568, Shop # 120.
November 2, 1992 – Company received a new 1992 Emergency One, ‘Protector’ 1250gpm pumper, Serial # 10938, Shop # 132.
November 24, 1997 – Company received a new 1997 International / Emergency One, 500gpm, brush truck, Serial # 17933, Shop # 149 , designated Brush 55.
2011 – Company received a 1996 Emergency One ‘Cyclone II’ 1250gpm pumper, Serial # 16511, Shop # 145.
October 7, 2021 – Company received a new 2021 Emergency One ‘Typhoon’ pumper, 1250gpm, 560g/30f tank, Serial # 143213, Shop # 133.