ΔE 12.5, fair: the same colour family, but not a straight swap. Sea Grey is noticeably lighter, more muted than Payne’s Grey.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Sea Grey is noticeably lighter, more muted than Payne’s Grey.
The same difference applies the other way round: Payne’s Grey is noticeably darker, more saturated.
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 Sea Grey on the colour wheel
All matches: Payne’s Grey equivalents · Sea Grey equivalents