Three tetranuclear heterometallic ZnII‐LnIII complexes of the 30‐membered [3+3] hexaimine macrocycle (LEt)6–, with general formula ZnII3LnIII(LEt)(NO3)2OAc·5H2O (LnIII = DyIII, ErIII, YbIII), were prepared using our established one‐pot synthesis methodology, whereby the individual components of the whole system are poised to assemble themselves into a mixed 3d/f4f macrocyclic system. This uses a 3:1:3:3 reaction of ZnII acetate, the appropriate LnIII nitrate, 1,4‐diformyl‐2,3‐dihydroxybenzene, and 1,2‐diaminoethane. These ten individual building blocks readily assemble into tetrametallic complexes, analogous to our previously reported examples with larger macrocycles. Identity was confirmed by IR spectroscopy (imine), micro‐ (C, H, N) and metal‐ (Zn, Ln) analysis, TGA (solvent content), and mass spectrometry. Magnetic properties were studied down to 2 K and with ac susceptibility measurements were used to check for slow relaxation of the magnetization characteristic of Single‐Molecule Magnet (SMM) behavior. As is often the case for single ion systems (only Ln is paramagnetic) no such behavior was observed. However, under an applied dc field, an out‐of‐phase ac susceptibility signal is seen for all three complexes. We speculate that shrinkage of macrocyclic ring size (30) compared to that of the original ZnII3DyIII system (33) has led to a less favorable coordination arrangement for the DyIII and ErIII ions through a change in the imposed coordination environment of the LnIII ion.