diff --git a/usr.bin/tr/tr.1 b/usr.bin/tr/tr.1
index 37e68f3e7ca1..2aee69cf4a37 100644
--- a/usr.bin/tr/tr.1
+++ b/usr.bin/tr/tr.1
@@ -334,6 +334,10 @@ should be used instead of explicit character ranges like
 and
 .Dq Li A-Z .
 .Pp
+.Dq Li [=equiv=]
+expression and collation for ranges
+are implemented for single byte locales only.
+.Pp
 System V has historically implemented character ranges using the syntax
 .Dq Li [c-c]
 instead of the