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The terminal uranium nitride linkage is a fundamental target in the study of f-orbital participation in metal-ligand multiple bonding but has previously eluded characterization in an isolable molecule. Here, we report the preparation of the terminal uranium(V) nitride complex [UN(Tren^TIPS)][Na(12-crown-4)₂] {in which Tren^TIPS = [N(CH₂CH₂NSiPrⁱ₃)₃]^3– and Prⁱ = CH(CH₃)₂} by reaction of the uranium(III) complex [U(Tren^TIPS)] with sodium azide followed by abstraction and encapsulation of the sodium cation by the polydentate crown ether 12-crown-4. Single-crystal x-ray diffraction reveals a uranium-terminal nitride bond length of 1.825(15) angstroms (where 15 is the standard uncertainty). The structural assignment is supported by means of ¹⁵N-isotopic labeling, electronic absorption spectroscopy, magnetometry, electronic structure calculations, elemental analyses, and liberation of ammonia after treatment with …