diff --git a/runtime/ftplugin/spajson.vim b/runtime/ftplugin/spajson.vim
new file mode 100644
index 0000000..d03d1d5
--- /dev/null
+++ b/runtime/ftplugin/spajson.vim
@@ -0,0 +1,14 @@
+" Vim filetype plugin
+" Language:	SPA JSON
+" Maintainer:	David Mandelberg <david@mandelberg.org>
+" Last Change:	2025 Mar 22
+
+if exists('b:did_ftplugin')
+  finish
+endif
+let b:did_ftplugin = 1
+
+setlocal comments=:###,:##,:#
+setlocal commentstring=#\ %s
+
+let b:undo_ftplugin = "setlocal comments< commentstring<"