Carbon (C) stocks in the forests of Reducing Emissions from Deforestation and Forest Degradation (REDD+) participating countries have to be estimated and monitored to determine accurate financial incentives and compensation. The research estimated the distribution of C stock across the different pools and management regimes of tropical Sal forest in the Terai Arc Landscape of Nepal. It applied a field measurement-based forest inventory method combined with the best predictive allometric model available, to increase accuracy and precision. Shrub and litter C were estimated by destructive method and Soil Organic Carbon (SOC) up to a depth of 30cm. Biomass data and samples were collected from 113 plots distributed throughout four different management regimes on 1.1million ha of forest in the landscape. The estimated average C stock in aboveground biomass, belowground biomass, shrub, litter, SOC and total were 105.58±17.05, 24.92±4.15, 0.23±0.06, 1.49±0.25, 96.53±8.76 and 228.76±19.61Mgha−1 respectively. The mass of total C stock varied from 291.55±42.51Mgha−1 in protected areas to 237.15±32.54Mgha−1 in community forests to 189.16±26.46Mgha−1 in government-managed forests and to 126.76±56.36Mgha−1 in other forests. These estimates of carbon stocks differed from earlier estimates based on biome-average datasets. They are consistent with those from similar forest type and site-specific earlier studies. Evidence of strong association of C stock with management regime provides valuable information for policy makers to make informed choice of management regime for the landscape.