ΔE 17.8, loose: different enough that you should pick on purpose. Salmon Rose is a little darker, much more saturated, warmer than Old Rose.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Salmon Rose is a little darker, much more saturated, warmer than Old Rose.
The same difference applies the other way round: Old Rose is a little lighter, 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 Old Rose on the colour wheel See Salmon Rose on the colour wheel
All matches: Old Rose equivalents · Salmon Rose equivalents