diff --git a/usr.bin/wc/wc.1 b/usr.bin/wc/wc.1
index 6d2ec6415a8f..80afcda711c9 100644
--- a/usr.bin/wc/wc.1
+++ b/usr.bin/wc/wc.1
@@ -57,7 +57,7 @@ character,
 and a word is defined as a string of characters delimited by white space
 characters.
 White space characters are the set of characters for which the
-.Xr isspace 3
+.Xr iswspace 3
 function returns true.
 If more than one input file is specified, a line of cumulative counts
 for all the files is displayed on a separate line after the output for
@@ -118,7 +118,7 @@ as well as the totals for both:
 .Sh DIAGNOSTICS
 .Ex -std
 .Sh SEE ALSO
-.Xr isspace 3
+.Xr iswspace 3
 .Sh COMPATIBILITY
 Historically, the
 .Nm
@@ -133,7 +133,7 @@ systems after
 modified the implementation to be consistent
 with the documentation.
 This implementation defines a ``word'' in terms of the
-.Xr isspace 3
+.Xr iswspace 3
 function, as required by
 .St -p1003.2 .
 .Sh STANDARDS
diff --git a/usr.bin/wc/wc.c b/usr.bin/wc/wc.c
index 6eb2602160e9..85a90c9b4d8b 100644
--- a/usr.bin/wc/wc.c
+++ b/usr.bin/wc/wc.c
@@ -59,6 +59,7 @@ __FBSDID("$FreeBSD$");
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <wctype.h>
 
 uintmax_t tlinect, twordct, tcharct;
 int doline, doword, dochar, domulti;
@@ -234,8 +235,7 @@ word:	gotsp = 1;
 			p += clen;
 			if (wch == L'\n')
 				++linect;
-			/* XXX Non-portable; should use iswspace() */
-			if (isspace(wch))
+			if (iswspace(wch))
 				gotsp = 1;
 			else if (gotsp) {
 				gotsp = 0;