Magnetic susceptibility, electrical resistivity and heat capacity data for single crystals of Ce(Rh,Ir)1−x(Co,Ir)xIn5 (0⩽x⩽1) have allowed us to construct a detailed phase diagram for this new family of heavy-fermion superconductors. CeRh1−xIrxIn5 displays superconductivity(SC) (Tc≲1K) over a wide range of composition, which develops out of and coexists (0.30≲x≲0.5) with a magnetically ordered state, with TN∼4K. For CeCo1−xRhxIn5, the superconducting state (Tc∼2.3K for x=0) becomes a magnetic state (TN∼4K, for x=1) with two phase transitions observed for 0.40≲x≲0.25. CeCo1−xIrxIn5 also shows two transitions for 0.30≲x≲0.75. For those alloys in which SC is found, a roughly linear relationship between Tc and the lattice parameter ratio c/a, was found, with composition as the implicit parameter. The interplay between magnetism and SC for CeRh1−x(Ir,Co)xIn5 and the possibility of two distinct superconducting states in CeCo1−xIrxIn5 are discussed.