The goal of this project was to provide the first estimates of blue carbon stocks and carbon accumulation rates in the high and low marsh zones of salt marshes from the Pacific Coast of Canada, within the Clayoquot Sound UNESCO Biosphere Reserve and Pacific Rim National Park Reserve on the Pacific Coast of Canada. To achieve this goal, 34 sediment cores were collected from seven salt marshes during summer (June-September) 2016. At each core site, marsh zone (high vs low) was determined using vegetation types surrounding the core site. Sediment cores were then collected using a simple percussion coring technique in which a length of two-inch (57 mm) diameter, PVC vacuum tubing fitted with a plastic core catcher (AMS Inc.) was hammered into the ground until the depth of refusal. At the GBK location, a steel sledge corer (AMS Inc.) was used to extract four cores before mechanical problems required switching to the simpler percussion method. For all sites, we recorded the deepest sediment depth at which peat was found (referred to as the "Peat Base"), as well as the sediment type at the base of each core.On all 34 cores, we measured core compaction, dry bulk density, % loss-on-ignition, and % organic carbon (using an elemental analyzer, on select number of samples). From these parameters we estimated % organic carbon (using a regression equation between % organic carbon and %LOI), soil carbon density, and carbon stocks measured to (a) the depth of the basal peat layer, (b) a depth of 20 cm, and (c) to the depth of the 30-year horizon (estimated in the 8 cores where 210Pb analysis was completed). Radioisotope (210Pb and 226Ra) measurements were conducted on 8 cores (4 from high marsh zone and 4 from low marsh zone) from marshes CBE, CRF, GBK, and TMF, to create age models for estimating carbon accumulation rates. This research was funded by a grant from the Commission for Environmental Cooperation to KEK, a Natural Sciences and Engineering Research Council [Discovery Grant RGPIN342251] to KEK; and Natural Sciences and Engineering Research Council Canada Research Chair Award to KEK. It received substantial in-kind field and laboratory support from Parks Canada (MGP).