diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
index 7a98f01067d68a7b15262ce88cc060b5a2e6094e..7763f88347547db956360e7a2835655636db9d5a 100644
--- a/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@ -1394,7 +1394,7 @@ __git_diff_common_options="--stat --numstat --shortstat --summary
 			--dirstat --dirstat= --dirstat-by-file
 			--dirstat-by-file= --cumulative
 			--diff-algorithm=
-			--submodule --submodule=
+			--submodule --submodule= --ignore-submodules
 "
 
 _git_diff ()
@@ -1435,11 +1435,11 @@ _git_difftool ()
 		return
 		;;
 	--*)
-		__gitcomp "--cached --staged --pickaxe-all --pickaxe-regex
-			--base --ours --theirs
-			--no-renames --diff-filter= --find-copies-harder
-			--relative --ignore-submodules
-			--tool="
+		__gitcomp_builtin difftool "$__git_diff_common_options
+					--base --cached --ours --theirs
+					--pickaxe-all --pickaxe-regex
+					--relative --staged
+					"
 		return
 		;;
 	esac