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Abstract Tidal salt marshes produce and emit CH₄. Therefore, it is critical to understand the biogeochemical controls that regulate CH₄spatial and temporal dynamics in wetlands. The prevailing paradigm assumes that acetoclastic methanogenesis is the dominant pathway for CH₄production, and higher salinity concentrations inhibit CH₄production in salt marshes. Recent evidence shows that CH₄is produced within salt marshes via methylotrophic methanogenesis, a process not inhibited by sulfate reduction. To further explore this conundrum, we performed measurements of soil–atmosphere CH₄and CO₂fluxes coupled with depth profiles of soil CH₄and CO₂pore water gas concentrations, stable and radioisotopes, pore water chemistry, and microbial community composition to assess CH₄production and fate within a temperate tidal salt marsh. We found unexpectedly high CH₄concentrations up to 145,000 μmol mol⁻¹positively correlated with S²⁻(salinity range: 6.6–14.5 ppt). Despite large CH₄production within the soil, soil–atmosphere CH₄fluxes were low but with higher emissions and extreme variability during plant senescence (84.3 ± 684.4 nmol m⁻² s⁻¹). CH₄and CO₂within the soil pore water were produced from young carbon, with most Δ¹⁴C‐CH₄and Δ¹⁴C‐CO₂values at or above modern. We found evidence that CH₄within soils was produced by methylotrophic and hydrogenotrophic methanogenesis. Several pathways exist after CH₄is produced, including diffusion into the atmosphere, CH₄oxidation, and lateral export to adjacent tidal creeks; the latter being the most likely dominant flux. Our findings demonstrate that CH₄production and fluxes are biogeochemically heterogeneous, with multiple processes and pathways that can co‐occur and vary in importance over the year. This study highlights the potential for high CH₄production, the need to understand the underlying biogeochemical controls, and the challenges of evaluating CH₄budgets and blue carbon in salt marshes.