We present CH₄ concentration [CH₄] and the partial pressure of CO₂ (pCO₂) in bulk sea ice from subarctic, land-fast sea ice in the Kapisillit fjord, Greenland. The bulk ice [CH₄] ranged from 1.8 to 12.1 nmol L⁻¹, which corresponds to a partial pressure range of 3 to 28 ppmv. This is markedly higher than the average atmospheric methane content of 1.9 ppmv. Most of the trapped methane within the sea ice was evidently contained inside bubbles, and only a minor portion was dissolved in the brine. The bulk ice pCO₂ ranged from 60 to 330 ppmv showing that sea ice at temperatures above −4 °C is under-saturated compared to the atmosphere (390 ppmv). Our study adds to the few existing studies of CH₄ and CO₂ in sea ice and concludes that sub-arctic sea can be a sink for atmospheric CO₂, while being a net source of CH₄. Processes related to the freezing and melting of sea ice represents large unknowns to the exchange of CO₂ but also CH₄. It is therefore imperative to assess the consequences of these unknowns through further field campaigns and targeted research under other sea ice conditions at both hemispheres.