Employment of H3L (= 2-(β-naphthalideneamino)-2-hydroxymethyl-1-propanol) in mixed-metal manganese-lanthanide cluster chemistry has led to the isolation of five new octametallic heteronuclear isostructural [MnIII6LnIII2] complexes. More specifically, the reaction of Mn(ClO4)2·6H2O with H3L and the corresponding lanthanide nitrate in MeCN in the presence of a base, NEt3, yielded four complexes with the general formula [MnIII6LnIII2O2(OH)2(H2O)2(HL)6(NO3)6]·6MeCN·0.5H2O (Ln: Gd, 1·6MeCN·0.5H2O; Tb, 2·6MeCN·0.5H2O; Dy, 3·6MeCN·0.5H2O; Er, 4·6MeCN·0.5H2O). Furthermore, the YIII analogue, [MnIII6YIII2O2(OH)2(H2O)2(HL)6(NO3)6]·6MeCN·0.5H2O (5·6MeCN·0.5H2O), was also synthesized in the same manner. All five clusters describe a central rod-like topology consisting of four face-sharing defective cubane metallic units, forming a planar hexametallic [MnIII4LnIII2] core, which is further capped by two MnIII ions. Dc magnetic susceptibility studies in the 5–300 K range for complexes 1–5 reveal the presence of dominant antiferromagnetic exchange interactions within the metallic clusters, while ac magnetic susceptibility measurements show temperature and frequency dependent out-of-phase signals for the DyIII analogue (3·6MeCN·0.5H2O), suggesting potential single molecule magnetism character. Furthermore, the YIII analogue yielded a diamagnetic ground-state for the [MnIII6] core, thus proving that the SMM character displayed by 3·6MeCN·0.5H2O is due to the presence of the DyIII centres.