Hydrogen is considered one of the options to be used as alternate fuel source to reduce carbon emissions. Towards this there is growing interest in using underground storage for hydrogen gas (H2) which can be stored in larger volumes, higher pressure than surface storage options would allow for. While underground well storage of natural gas is widely understood; there is far less experience in storing H2 only or H2 in blend with natural gas. An area of knowledge gap is the compatibility of metallic materials that need to be used for well construction for underground storage as the assessment of risk for Hydrogen Embrittlement (HE) would need to be addressed. In this work, some of the common materials used in well construction for various oil and gas wells, i.e., high strength quenched and tempered 41XX type Cr-Mo steel, Super Martensitic Stainless Steel (Super 13Cr) and Age Hardenable Nickel alloy grade Alloy 925 (UNS N09925) all with similar yield strength levels have been assessed for compatibility with high pressure H2 gas. Evaluation was mainly performed via Fracture Toughness testing in both inert and high pressure H2 gas environment per ASTM E1820.1 Details of this assessment and post testing evaluation of the specimens will be provided in this paper.