The phenomenon of superconductivity normally involves the pairing of two electrons of opposite spin, to create a bound Cooper pair in a spin-singlet configuration. A more exotic variant of superconductivity can combine two electrons of identical spin, in a triplet configuration. Triplet superconductors have been proposed to exhibit a variety of technologically valuable topological properties – but candidate materials are rare, and no bulk 3D system has yet been conclusively proven to host triplet superconductivity. One promising material is the heavy fermion superconductor uranium ditelluride (UTe₂), which was recently discovered to exhibit numerous characteristics indicative of spin-triplet pairing. However, uncertainty regarding the nature of this material’s electronic structure has clouded interpretation of the normal state fermiology and associated topological character. Here we directly probe the Fermi surface of UTe₂ by magnetic quantum oscillations on ultra-pure crystals, as characterised by their high critical temperature