Burgundy vs Willow Bark

How close are they?

ΔE 17.0, loose: different enough that you should pick on purpose. Willow Bark is a little darker, much more muted than Burgundy.

Can I use Willow Bark instead of Burgundy?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Willow Bark is a little darker, much more muted than Burgundy.

Can I use Burgundy instead of Willow Bark?

The same difference applies the other way round: Burgundy is a little lighter, much 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.