As the heaviest stable element, the electronic structure of bismuth (Bi) is strongly influenced by relativistic effects, thus decreasing the energies of its 6s and 6p orbitals. Consequences of this unique electronic features are the well-known inert-pair effect or the strong Lewis acidity. In certain cases, homolysis of RBi-X bonds becomes feasible due to the preferential stability of the RBi radical over the ionized heterolysis product RBi + . In principle, if the RBi• and X•, generated from homolysis are stable, it is possible that this complex exists in both diamagnetic and paramagnetic form: a Radical Equilibrium Complex (REC) (Fig. ). Examples of Bi REC are scarce, and the few reported homolysis cases of the Bi-X bond are mainly irreversible, due to the high reactivity of the ensuing Bi radical species. Fundamental studies on a Bi-Mo catalyst for the SOHIO process conducted by Hanna suggested that Bi(II) intermediates-formed after thermal homolysis of the Bi(III) bearing bulky phenolates-could be responsible for the formation of allyl radicals from propene. 19c Similar reactivity with bulky phenolate anions was later observed by Evans in a unique C-H bismuthylation of phenols. In 2018, Coles demonstrated that the Bi(III)-O bond in a R2Bi-OTEMP compound is in equilibrium with the corresponding R2Bi(II) and TEMPO•. Collectively, these precedents pointed to a facile thermal Bi-O bond scission of bulky oxy-type anions that can stabilize O centered radicals. 19d, g Yet, the origin and factors that influence this process still remain unclear and investigations on such unusual chemical properties would be desirable. Herein we report on the synthesis, reactivity and structural characterization of a Bi REC, whose Bi-O homolyzes reversibly at room temperature without the need for irradiation (Fig. ). We demonstrate that such complex permits fast, and mild activation of ammonia and water-among other alcohols and amines-resulting in well-defined Bi(III) amido and alkoxy compounds. We suggest that upon coordination to Bi(II), ammines and alcohols undergo X-H bond weakening, thus permitting their facile radical activation. In addition, we propose that the novel pincer-based Bi(III)-NR2 compounds show reactivity with a triad of H + , H - and H • sources. This rich and broad reactivity opens the door to the design of strategies for transferring and manipulating the NH2 moiety upon ammonia activation, a highly coveted and important process toward considering NH3 as viable building block.