Coastal wetlands are being lost at an alarming rate and thus wetland restoration is an important way to recruit coastal wetlands as an ally in our fight against climate change. To better understand and maximize the effectiveness of wetland restoration, it is important to evaluate the success of these restoration projects. In this study, we measured sediment accumulation and soil carbon density in North Campus Open Space, a recently restored wetland near the campus of UC Santa Barbara. The objectives of this study were to 1) assess rates of sediment accumulation since restoration, 2) evaluate spatial heterogeneity in sediment accumulation and soil carbon density, and 3) use this information to better understand the mechanisms that define the relationship between sediment accumulation and surface soil carbon storage to better predict carbon accumulation. Sediment accumulation rate averaged 2.16 mm/year, with a range of 0.4 mm/yr to 5.4 mm/yr. Sediment accumulation, surface soil carbon density, and subsurface carbon density all varied significantly by plot location. The spatial dynamics of vertical accretion were primarily driven by mineral rather than organic material, whereas surface soil carbon was primarily driven by aboveground plant biomass. Sediment accumulation was greatest downstream, whereas soil carbon accumulation was greatest upstream at the freshwater stream inputs. Some areas showed a negative relationship between sediment accumulation and soil carbon density, with high sediment accumulation associated with low surface soil carbon density. Although wetlands are touted to mitigate sea level rise and climate change through sediment accretion and carbon sequestration, these results suggest that sediment accumulation and carbon accumulation do not necessarily co-occur. The results imply that sediment accumulation alone cannot reliably predict carbon accumulation.