  We decompose Pantheon+ Type Ia supernovae (SN) in hemispheres on the sky
finding angular variations up to $4$ km/s/Mpc in the Hubble constant $H_0$ both
in the SH0ES redshift range $0.0233 < z < 0.15$ and in extended redshift
ranges. The variations are driven largely by variations in absolute magnitude
from SN in Cepheid hosts, but are reinforced by SN in the Hubble flow. $H_0$ is
larger in a hemisphere encompassing the CMB dipole direction. The variations we
see exceed the errors on the recent SH0ES determination, $H_0 = 73.04 \pm 1.04$
km/s/Mpc, but are not large enough to explain early versus late Universe
discrepancies in the Hubble constant. Nevertheless, the Cepheid-SN distance
ladder is anisotropic at current precision. The anisotropy may be due to a
breakdown in the Cosmological Principle, or mundanely due to a statistical
fluctuation in a small sample of SN in Cepheid host galaxies.
