RATIONALE Cryogenic trapping of methane is essential for bulk and clumped isotope analyses, requiring adsorbent materials that enable efficient recovery and preserve isotopic signatures. This study evaluates the performance – capacity, isotopic fractionation, and ease of use – of silica gels, zeolite molecular sieves, and activated carbon under various trapping and desorption conditions. A focus is set on the preservation of methane clumped isotope signatures. METHODS A well-characterized methane reference gas (40 mL) was cryofocused at 77 K in containers filled with silica gels, zeolite molecular sieves (5A and 13X), or activated carbon alongside non-loaded containers. After loading, the containers were warmed in a water bath (21 to 95 °C) for various dwell times. The bulk (𝛿D-CH 4 and 𝛿 13C-CH 4) and clumped (∆ 13CH 3D and ∆ 12CH 2D 2) isotopic composition of the desorbed methane were measured against the untreated reference gas using novel quantum cascade laser absorption spectroscopy (QCLAS). RESULTS The best results were achieved with coarse-grained (1-3 mm) silica gels heated to 50 °C for at least five minutes or at 21 to 22 °C for a minimum of 120 minutes. Elevated desorption temperatures (80 °C to 95 °C) compromised clumped isotope signatures. Although effective for gas trapping, zeolite molecular sieves, and activated carbon introduced significant bulk and clumped isotopic shifts due to catalytic effects and chromatographic isotopologue separation. Methane cryofocused without adsorbents retained its bulk and clumped isotopic composition without significant fractionation. CONCLUSIONS Among the tested adsorbents, silica gels demonstrated superior performance, preserving δ 13C-CH 4, δD-CH 4, ∆ 13CH 3D, and ∆ 12CH 2D 2 values close to or within performance targets while offering high adsorption capacity, reproducibility, and ease of regeneration. Adsorbent-free cryotrapping is a viable alternative for sufficiently large methane volumes, where vapor pressure isotope effects (VPIEs) become negligible. However, cryogenic adsorbents remain indispensable for ensuring isotopic accuracy for small sample volumes and high-precision applications.