ΔE 13.9, fair: the same colour family, but not a straight swap. Blue is a little lighter, much more saturated, warmer than Payne’s Grey.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Blue is a little lighter, much more saturated, warmer than Payne’s Grey.
The same difference applies the other way round: Payne’s Grey is a little darker, much more muted, cooler.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Payne’s Grey on the colour wheel See Blue on the colour wheel
All matches: Payne’s Grey equivalents · Blue equivalents