diff --git a/usr.bin/sort/file.h b/usr.bin/sort/file.h
--- a/usr.bin/sort/file.h
+++ b/usr.bin/sort/file.h
@@ -41,8 +41,8 @@
 #define	SORT_HEAPSORT	3
 #define	SORT_RADIXSORT  4
 
-#define	DEFAULT_SORT_ALGORITHM SORT_HEAPSORT
-#define	DEFAULT_SORT_FUNC heapsort
+#define	DEFAULT_SORT_ALGORITHM SORT_MERGESORT
+#define	DEFAULT_SORT_FUNC mergesort
 
 /*
  * List of data to be sorted.