The island of Newfoundland has extensive peatlands known to act as net carbon sinks over centuries and millennia. There is increasing interest in advancing peatland conservation and terrestrial land protection for their climate mitigation potential, yet the potential role of Newfoundland peatlands in nature-based climate solutions is not well known due to uncertainties in their carbon storage capacities and areal extents. To address this knowledge gap, we collected long soil cores from eight peatland sites situated in different ecoregions across Newfoundland. We measured carbon contents using elemental analysis, and dated cores using radioisotopes (i.e., Pb-210, C-14) to calculate short- and long-term rates of carbon burial. As well, we compiled soil (e.g., peat depths, radiocarbon dates) and mapping information from archived government reports and the more recent Canadian National Wetland Inventory to expand our geographic range of soil carbon data and leverage existing information from remote areas. Results show that Newfoundland peatlands exhibit characteristics of both bogs and fens, and have highly variable peat depths. Basal ages of the peat cores we collected date back as many as 7,000-8,000 calibrated years before present despite differing between 0.5-5 m in depth and being situated in different ecozones. In this poster, we examine the geographical variation of soil carbon stocks and rates of carbon burial among Newfoundland peatlands, and describe how it helps inform identification and mapping of peatlands for conservation and greenhouse gas inventories.