ΔE 15.3, loose: different enough that you should pick on purpose. Natural Steel is a little lighter, more muted than Steel Red.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Natural Steel is a little lighter, more muted than Steel Red.
The same difference applies the other way round: Steel Red is a little 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 Steel Red on the colour wheel See Natural Steel on the colour wheel
All matches: Steel Red equivalents · Natural Steel equivalents