ΔE 9.7, close: similar, with a visible difference side by side. Aged White is a little darker, more saturated than Birch.
Usually, if you are not matching paint already on the model. Close match (ΔE 10). Aged White is a little darker, more saturated than Birch.
The same difference applies the other way round: Birch is a little lighter, more muted.
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 Birch on the colour wheel See Aged White on the colour wheel
All matches: Birch equivalents · Aged White equivalents