High-performance　magnetocaloric　materials　should　have　a　large　reversible　magnetocaloric　effect　and　good　heat　exchange　capability.　Here,　we　developed　a　Ni48.1Co2.9Mn35.0In14.0　metamagnetic　shape　memory　microwire　with　a　large　and　reversible　inverse　magnetocaloric　effect.　As　compared　to　the　bulk　counterpart,　the　microwire　shows　a　better　combination　of　magnetostructural　transformation　parameters　(magnetization　difference　across　transformation　Delta　M,　transformation　entropy　change　Delta　S-tr,　thermal　hysteresis　Delta　T-hys,　and　transformation　interval　Delta　T-int)　and　thus　greatly　reduced　critical　field　required　for　complete　and　reversible　magnetic-field-induced　transformation.　A　strong　and　reversible　metamagnetic　transition　occurred　in　the　microwire,　which　facilitates　the　achievement　of　large　reversible　magnetoresponsive　effects.　Consequently,　a　large　and　reversible　magnetic-field-induced　entropy　change　Delta　S-m　of　12.8　J　kg(-1)　K-1　under　5　T　was　achieved　in　the　microwire,　which　is　the　highest　value　reported　heretofore　in　Ni-Mn-based　magnetic　shape　memory　wires.　Furthermore,　since　microwires　have　a　high　surface/volume　ratio,　they　exhibit　very　good　heat　exchange　capability.　The　present　Ni48.1Co2.9Mn35.0In14.0　microwire　shows　great　potential　for　magnetic　refrigeration.　This　study　may　stimulate　further　development　of　high-performance　magnetocaloric　wires　for　high-efficiency　and　environmentally　friendly　solid-state　cooling.　Published　by　AIP　Publishing.