diff --git a/.changeset/twelve-wombats-chew.md b/.changeset/twelve-wombats-chew.md
new file mode 100644
index 000000000..4d0e936bf
--- /dev/null
+++ b/.changeset/twelve-wombats-chew.md
@@ -0,0 +1,5 @@
+---
+"@opennextjs/aws": patch
+---
+
+fix(converters): Ensure x-forwarded-proto is set to http when running locally
diff --git a/packages/open-next/src/overrides/converters/edge.ts b/packages/open-next/src/overrides/converters/edge.ts
index 7cd6d8aed..792270501 100644
--- a/packages/open-next/src/overrides/converters/edge.ts
+++ b/packages/open-next/src/overrides/converters/edge.ts
@@ -36,6 +36,12 @@ const converter: Converter<InternalEvent, InternalResult | MiddlewareResult> = {
       ? (cookieParser.parse(cookieHeader) as Record<string, string>)
       : {};
 
+    // This is to make libraries (e.g. next-auth) that rely on this header to work out of the box in `opennextjs-cloudflare preview`.
+    // See https://github.com/nextauthjs/next-auth/blob/main/packages/core/src/lib/utils/env.ts#L95-L96
+    if (url.hostname === "localhost") {
+      headers["x-forwarded-proto"] = url.protocol.slice(0, -1); // Remove the trailing ':'
+    }
+
     return {
       type: "core",
       method,
diff --git a/packages/open-next/src/overrides/wrappers/express-dev.ts b/packages/open-next/src/overrides/wrappers/express-dev.ts
index ae2fcd6b4..14bc9fc91 100644
--- a/packages/open-next/src/overrides/wrappers/express-dev.ts
+++ b/packages/open-next/src/overrides/wrappers/express-dev.ts
@@ -34,6 +34,12 @@ const wrapper: WrapperHandler = async (handler, converter) => {
   });
 
   app.all("*paths", async (req, res) => {
+    if (req.protocol === "http" && req.hostname === "localhost") {
+      // This is used internally by Next.js during redirects in server actions. We need to set it to the origin of the request.
+      process.env.__NEXT_PRIVATE_ORIGIN = `${req.protocol}://${req.hostname}`;
+      // This is to make `next-auth` and other libraries that rely on this header to work locally out of the box.
+      req.headers["x-forwarded-proto"] = req.protocol;
+    }
     const internalEvent = await converter.convertFrom(req);
     const streamCreator: StreamCreator = {
       writeHeaders: (prelude) => {