Methane fluxes and vertical profiles of CH₄ mixing ratios were measured in different German soils both in situ and in soil cores. Atmospheric CH₄ was oxidized in the soil by microorganisms resulting in an average CH₄ flux of −1.39±1.5 μmol‐CH₄ m⁻² h⁻¹. Methane deposition showed only a weak positive correlation (r² = 0.38) with soil temperature but a relatively strong negative correlation (r² = 0.61) with soil moisture indicating limitation of the CH₄ flux by gas transport. Diffusion experiments in soil cores showed that gas transport between atmosphere and soil was faster than microbial CH₄ oxidation. However, the diffusion from the gas‐filled soil pores to the CH₄ oxidizing microorganisms may have been limiting. The main CH₄₋ oxidizing activity was located in a few centimeter thick subsurface soil layer at the top of the A_h horizon, whereas no activity was found in the overlying O horizons and in deep soil below about 20‐cm depth. In contrast, the highest CO₂ production was found in the topmost O horizon. The effective diffusion coefficient of CH₄ in soil was determined using a method based on relaxation experiments with argon. The diffusion coefficient was used to model the CH₄ oxidation in soil cores from the vertical profiles of CH₄ mixing ratios. The thus calculated CH₄ oxidation rates and their localization in the soil profile compared fairly well with those determined directly from incubated soil samples. Fluxes were similar within a factor of 2–4 whether derived from the model, calculated from the measured CH4 oxidation rates of soil samples, or measured directly.

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