diff --git a/runtime/filetype.vim b/runtime/filetype.vim
index 6b0e5d611e..a132a4a545 100644
--- a/runtime/filetype.vim
+++ b/runtime/filetype.vim
@@ -893,6 +893,9 @@ au BufNewFile,BufRead *.fish			setf fish
 " Flatpak config
 au BufNewFile,BufRead */flatpak/repo/config	setf dosini
 
+" Flix
+au BufNewFile,BufRead *.flix			setf flix
+
 " Focus Executable
 au BufNewFile,BufRead *.fex,*.focexec		setf focexec
 
diff --git a/src/testdir/test_filetype.vim b/src/testdir/test_filetype.vim
index 0c74ffba7a..844bdb3255 100644
--- a/src/testdir/test_filetype.vim
+++ b/src/testdir/test_filetype.vim
@@ -287,6 +287,7 @@ def s:GetFilenameChecks(): dict<list<string>>
     fgl: ['file.4gl', 'file.4gh', 'file.m4gl'],
     firrtl: ['file.fir'],
     fish: ['file.fish'],
+    flix: ['file.flix'],
     focexec: ['file.fex', 'file.focexec'],
     form: ['file.frm'],
     forth: ['file.ft', 'file.fth', 'file.4th'],