Techniques facilitating custom thermal shields for cryogenic environments are provided. In one example, a cryostat can comprise a thermal shield extending between a thermal stage and a base structure coupled to a bottom plate of an outer vacuum chamber. The thermal stage can be coupled to a top plate of the outer vacuum chamber. The thermal shield can provide access to a sample mounting surface encompassed within the thermal shield from a region external to the outer vacuum chamber via the top and bottom plates of the outer vacuum chamber.