ΔE 13.5, fair: the same colour family, but not a straight swap. Interior Grey Green is a little darker, more muted, cooler than Sky BS381C/210.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Interior Grey Green is a little darker, more muted, cooler than Sky BS381C/210.
The same difference applies the other way round: Sky BS381C/210 is a little lighter, more saturated, warmer.
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 Sky BS381C/210 on the colour wheel See Interior Grey Green on the colour wheel
All matches: Sky BS381C/210 equivalents · Interior Grey Green equivalents