We have investigated the influence of both miscut angle and miscut direction of Y2O3-stabilized ZrO2 (YSZ) (100) single crystal substrates on the azimuthal domain structure of SrRuO3 electrode layers as well as of La-substituted Bi4Ti3O12 (BLT) ferroelectric thin films, both grown on these substrates by pulsed laser deposition. X-ray diffraction Φ scan and pole figure characterizations revealed that the YSZ miscut direction is more effective to uniformly reduce the number of azimuthal domain variants in the films than the YSZ miscut direction. The BLT films on YSZ(100) substrates with miscut angle of 5° and  miscut direction involve only half the number of azimuthal domains, compared to the BLT films on exactly cut YSZ(100) substrates. Atomic force microscopy and plan-view transmission electron microscopy also confirmed that almost all BLT grains on these miscut YSZ(100) substrates are arranged along only two (out of four) specific azimuthal directions. The BLT films on YSZ(100) substrates with 5° miscut towards YSZ showed an about 1.3 times higher remanent polarization (Pr=12.5 μC/cm2) than the BLT films on exactly cut YSZ(100) substrates (Pr=9.5 μC/cm2), due most probably to a lower areal density of azimuthal domain boundaries. It thus appears that reducing the structural domains can be an effective way to further enhance the ferroelectric properties of multiply twinned, epitaxial ferroelectric films.