Conversion of forest to other land uses is a major contributor to climate change. The coastal forests of Tanzania have increasingly been recognized as being of global biodiversity importance, due to high rates of species endemism. Rates of forest loss are similar to those of other tropical regions, resulting in increasing levels of threat for the biological values within the remaining forest and potentially significant source of CO2 emissions. This study estimated the remaining cover and carbon stock of Tanzania's coastal forests and the CO2 emissions due to forest loss between c. 1990 and c. 2007. Coastal Tanzania contained over 273 700 ha of forest in 2007. Deforestation rates in the area have slowed from 1.0% yr−1, or > 3735 ha yr−1 during the 1990s, to 0.4% yr−1, or > 1233 ha yr−1 during 2000–2007. Despite lower deforestation rates in 2000–2007, the percentage forest lost from within reserved areas has remained steady at 0.2% yr−1 for both time periods. CO2 emissions from deforestation slowed from at least 0.63 Mt CO2 yr−1 in 1990–2000 to at least 0.20 Mt CO2 yr−1 in 2000–2007. Regional forest clearance in Tanzania is highly dynamic; while rates have slowed since 2000, forest habitat conversion has continued and there is no guarantee that future rates will remain low. A rigorous policy on reducing emissions from deforestation and degradation (REDD) should be implemented to avoid future increases in deforestation rates.