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Hydrogen-rich superconductors are promising candidates to achieve room-temperature superconductivity. However, the extreme pressures needed to stabilize these structures significantly limit their practical applications. An effective strategy to reduce the external pressure is to add a light element M that binds with H to form MH x units, acting as a chemical precompressor. We exemplify this idea by performing ab initio calculations of the Ac–Be–H phase diagram, proving that the metallization pressure of Ac–H binaries, for which critical temperatures as high as 200 K were predicted at 200 GPa, can be significantly reduced via beryllium incorporation. We identify three thermodynamically stable ( AcBe 2 H 10 , AcBeH 8 , and AcBe 2 H 14 ) and four metastable compounds (fcc AcBeH 8 , AcBeH 10 , AcBeH 12 and AcBe 2 H 16 ). All of them are superconductors. In particular, fcc AcBeH 8 remains dynamically stable down to 10 GPa, where it exhibits a superconducting-transition temperature T c of 181 K. The Be–H bonds are responsible for the exceptional properties of these ternary compounds and allow them to remain dynamically stable close to ambient pressure. Our results suggest that high- T c superconductivity in hydrides is achievable at low pressure and may stimulate experimental synthesis of ternary hydrides.