diff --git a/packages/tailwindcss-language-service/src/util/languages.ts b/packages/tailwindcss-language-service/src/util/languages.ts
index ba99c0e..53c3593 100644
--- a/packages/tailwindcss-language-service/src/util/languages.ts
+++ b/packages/tailwindcss-language-service/src/util/languages.ts
@@ -24,6 +24,7 @@ export const htmlLanguages = [
   'mustache',
   'njk',
   'nunjucks',
+  'phoenix-heex',
   'php',
   'razor',
   'slim',