Godrej and Boyce Mfg. Co. Ltd. is conserving thousands of acres of mangrove forest along the western bank of Thane Creek (19º03’31.12” N, 72º56’31.54” E to 19º06’31.43” N to 72º56’31.54” E) since the decade of 1940s. In this rich biodiverse forest, we have recorded 16 species of mangrove and mangrove associated plants. These forests provide ecosystem services like prevention of coastal erosion, habitat for wildlife, livelihoods for local fisherfolk, research and education avenue for academia and regulation of local climate. This paper explains material and methodology used to measure sequestered carbon using data of past 3 years. Annually this forest sequesters 6 lakh tons of CO2 its potential annual increment value iaround 50,000 tons of equivalent CO2. This carbon sequestration service is very valuable considering high emission of CO2 in the Mumbai Metropolitan Region and its impact on climate change. The paper also highlights importance of this project to the society and need to sensitize stakeholders for the mangrove conservation.