ΔE 14.0, fair: the same colour family, but not a straight swap. Pale Blue is noticeably lighter, more muted, warmer than Pastel Blue.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Pale Blue is noticeably lighter, more muted, warmer than Pastel Blue.
The same difference applies the other way round: Pastel Blue is noticeably darker, more saturated, 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 Pastel Blue on the colour wheel See Pale Blue on the colour wheel
All matches: Pastel Blue equivalents · Pale Blue equivalents