diff --git a/build-scripts/gulp/locale-data.js b/build-scripts/gulp/locale-data.js
index 4da1d8f218cd..4cf91711d495 100755
--- a/build-scripts/gulp/locale-data.js
+++ b/build-scripts/gulp/locale-data.js
@@ -24,8 +24,11 @@ const convertToJSON = async (
 ) => {
   let localeData;
   try {
+    // use "pt" for "pt-BR", because "pt-BR" is unsupported by @formatjs
+    const language = lang === "pt-BR" ? "pt" : lang;
+
     localeData = await readFile(
-      join(formatjsDir, pkg, subDir, `${lang}.js`),
+      join(formatjsDir, pkg, subDir, `${language}.js`),
       "utf-8"
     );
   } catch (e) {