diff --git a/apps/webapp/app/routes/api.v1.projects.$projectRef.$env.ts b/apps/webapp/app/routes/api.v1.projects.$projectRef.$env.ts
index 53f2cad895..e0349aab55 100644
--- a/apps/webapp/app/routes/api.v1.projects.$projectRef.$env.ts
+++ b/apps/webapp/app/routes/api.v1.projects.$projectRef.$env.ts
@@ -5,6 +5,7 @@ import { env as processEnv } from "~/env.server";
 import {
   authenticatedEnvironmentForAuthentication,
   authenticateRequest,
+  branchNameFromRequest,
 } from "~/services/apiAuth.server";
 
 const ParamsSchema = z.object({
@@ -32,7 +33,8 @@ export async function loader({ request, params }: LoaderFunctionArgs) {
   const environment = await authenticatedEnvironmentForAuthentication(
     authenticationResult,
     projectRef,
-    env
+    env,
+    branchNameFromRequest(request)
   );
 
   const result: GetProjectEnvResponse = {
diff --git a/apps/webapp/app/routes/api.v1.projects.$projectRef.background-workers.$envSlug.$version.ts b/apps/webapp/app/routes/api.v1.projects.$projectRef.background-workers.$envSlug.$version.ts
index 90dc7a3661..6b044c9e83 100644
--- a/apps/webapp/app/routes/api.v1.projects.$projectRef.background-workers.$envSlug.$version.ts
+++ b/apps/webapp/app/routes/api.v1.projects.$projectRef.background-workers.$envSlug.$version.ts
@@ -4,6 +4,7 @@ import { prisma } from "~/db.server";
 import {
   authenticateRequest,
   authenticatedEnvironmentForAuthentication,
+  branchNameFromRequest,
 } from "~/services/apiAuth.server";
 import zlib from "node:zlib";
 
@@ -29,7 +30,8 @@ export async function loader({ params, request }: LoaderFunctionArgs) {
   const environment = await authenticatedEnvironmentForAuthentication(
     authenticationResult,
     parsedParams.data.projectRef,
-    parsedParams.data.envSlug
+    parsedParams.data.envSlug,
+    branchNameFromRequest(request)
   );
 
   // Find the background worker and tasks and files
diff --git a/apps/webapp/app/routes/api.v1.projects.$projectRef.envvars.$slug.$name.ts b/apps/webapp/app/routes/api.v1.projects.$projectRef.envvars.$slug.$name.ts
index 13784b8110..e3081b090e 100644
--- a/apps/webapp/app/routes/api.v1.projects.$projectRef.envvars.$slug.$name.ts
+++ b/apps/webapp/app/routes/api.v1.projects.$projectRef.envvars.$slug.$name.ts
@@ -5,6 +5,7 @@ import { prisma } from "~/db.server";
 import {
   authenticateRequest,
   authenticatedEnvironmentForAuthentication,
+  branchNameFromRequest,
 } from "~/services/apiAuth.server";
 import { EnvironmentVariablesRepository } from "~/v3/environmentVariables/environmentVariablesRepository.server";
 
@@ -30,7 +31,8 @@ export async function action({ params, request }: ActionFunctionArgs) {
   const environment = await authenticatedEnvironmentForAuthentication(
     authenticationResult,
     parsedParams.data.projectRef,
-    parsedParams.data.slug
+    parsedParams.data.slug,
+    branchNameFromRequest(request)
   );
 
   // Find the environment variable
@@ -106,7 +108,8 @@ export async function loader({ params, request }: LoaderFunctionArgs) {
   const environment = await authenticatedEnvironmentForAuthentication(
     authenticationResult,
     parsedParams.data.projectRef,
-    parsedParams.data.slug
+    parsedParams.data.slug,
+    branchNameFromRequest(request)
   );
 
   // Find the environment variable
diff --git a/apps/webapp/app/routes/api.v1.projects.$projectRef.envvars.$slug.ts b/apps/webapp/app/routes/api.v1.projects.$projectRef.envvars.$slug.ts
index fe2d77cbf8..188290ae8a 100644
--- a/apps/webapp/app/routes/api.v1.projects.$projectRef.envvars.$slug.ts
+++ b/apps/webapp/app/routes/api.v1.projects.$projectRef.envvars.$slug.ts
@@ -4,6 +4,7 @@ import { z } from "zod";
 import {
   authenticateRequest,
   authenticatedEnvironmentForAuthentication,
+  branchNameFromRequest,
 } from "~/services/apiAuth.server";
 import { EnvironmentVariablesRepository } from "~/v3/environmentVariables/environmentVariablesRepository.server";
 
@@ -28,7 +29,8 @@ export async function action({ params, request }: ActionFunctionArgs) {
   const environment = await authenticatedEnvironmentForAuthentication(
     authenticationResult,
     parsedParams.data.projectRef,
-    parsedParams.data.slug
+    parsedParams.data.slug,
+    branchNameFromRequest(request)
   );
 
   const jsonBody = await request.json();
@@ -75,7 +77,8 @@ export async function loader({ params, request }: LoaderFunctionArgs) {
   const environment = await authenticatedEnvironmentForAuthentication(
     authenticationResult,
     parsedParams.data.projectRef,
-    parsedParams.data.slug
+    parsedParams.data.slug,
+    branchNameFromRequest(request)
   );
 
   const repository = new EnvironmentVariablesRepository();
diff --git a/apps/webapp/app/services/apiAuth.server.ts b/apps/webapp/app/services/apiAuth.server.ts
index 989aeef8e9..e5689f9ec6 100644
--- a/apps/webapp/app/services/apiAuth.server.ts
+++ b/apps/webapp/app/services/apiAuth.server.ts
@@ -497,7 +497,9 @@ export async function authenticatedEnvironmentForAuthentication(
         throw json({ error: "Project not found" }, { status: 404 });
       }
 
-      if (!branch) {
+      const sanitizedBranch = sanitizeBranchName(branch);
+
+      if (!sanitizedBranch) {
         const environment = await prisma.runtimeEnvironment.findFirst({
           where: {
             projectId: project.id,
@@ -526,8 +528,8 @@ export async function authenticatedEnvironmentForAuthentication(
       const environment = await prisma.runtimeEnvironment.findFirst({
         where: {
           projectId: project.id,
-          slug: slug,
-          branchName: sanitizeBranchName(branch),
+          type: "PREVIEW",
+          branchName: sanitizedBranch,
           archivedAt: null,
         },
         include: {
@@ -574,7 +576,9 @@ export async function authenticatedEnvironmentForAuthentication(
         throw json({ error: "Project not found" }, { status: 404 });
       }
 
-      if (!branch) {
+      const sanitizedBranch = sanitizeBranchName(branch);
+
+      if (!sanitizedBranch) {
         const environment = await prisma.runtimeEnvironment.findFirst({
           where: {
             projectId: project.id,
@@ -596,8 +600,8 @@ export async function authenticatedEnvironmentForAuthentication(
       const environment = await prisma.runtimeEnvironment.findFirst({
         where: {
           projectId: project.id,
-          slug: slug,
-          branchName: sanitizeBranchName(branch),
+          type: "PREVIEW",
+          branchName: sanitizedBranch,
           archivedAt: null,
         },
         include: {
diff --git a/apps/webapp/app/v3/gitBranch.ts b/apps/webapp/app/v3/gitBranch.ts
index 109de645b9..06c76f0624 100644
--- a/apps/webapp/app/v3/gitBranch.ts
+++ b/apps/webapp/app/v3/gitBranch.ts
@@ -29,7 +29,7 @@ export function isValidGitBranchName(branch: string): boolean {
   return true;
 }
 
-export function sanitizeBranchName(ref: string): string | null {
+export function sanitizeBranchName(ref: string | undefined): string | null {
   if (!ref) return null;
   if (ref.startsWith("refs/heads/")) return ref.substring("refs/heads/".length);
   if (ref.startsWith("refs/remotes/")) return ref.substring("refs/remotes/".length);