diff --git a/lib/linguist/languages.yml b/lib/linguist/languages.yml
index 15a135e1..340c7682 100644
--- a/lib/linguist/languages.yml
+++ b/lib/linguist/languages.yml
@@ -1307,6 +1307,8 @@ Prolog:
   type: programming
   color: "#74283c"
   primary_extension: .prolog
+  extensions: 
+  - .pl
 
 Protocol Buffer:
   type: markup