diff --git a/src/controllers/branch-controller.ts b/src/controllers/branch-controller.ts
index adb3fef..ea98c88 100644
--- a/src/controllers/branch-controller.ts
+++ b/src/controllers/branch-controller.ts
@@ -20,7 +20,6 @@ import HttpStatus from "../interfaces/http-status";
 import { RequestWithUser } from "../interfaces/user";
 
 type BranchCreate = {
-  code?: string;
   status?: Status;
   taxNo: string;
   nameEN: string;
@@ -40,7 +39,6 @@ type BranchCreate = {
 };
 
 type BranchUpdate = {
-  code?: string;
   status?: "ACTIVE" | "INACTIVE";
   taxNo?: string;
   nameEN?: string;
@@ -157,41 +155,50 @@ export class BranchController extends Controller {
 
   @Post()
   async createBranch(@Request() req: RequestWithUser, @Body() body: BranchCreate) {
-    if (body.provinceId || body.districtId || body.subDistrictId || body.headOfficeId) {
-      const [province, district, subDistrict, branch] = await prisma.$transaction([
-        prisma.province.findFirst({ where: { id: body.provinceId || undefined } }),
-        prisma.district.findFirst({ where: { id: body.districtId || undefined } }),
-        prisma.subDistrict.findFirst({ where: { id: body.subDistrictId || undefined } }),
-        prisma.branch.findFirst({ where: { id: body.headOfficeId || undefined } }),
-      ]);
-      if (body.provinceId && !province)
-        throw new HttpError(
-          HttpStatus.BAD_REQUEST,
-          "Province cannot be found.",
-          "missing_or_invalid_parameter",
-        );
-      if (body.districtId && !district)
-        throw new HttpError(
-          HttpStatus.BAD_REQUEST,
-          "District cannot be found.",
-          "missing_or_invalid_parameter",
-        );
-      if (body.subDistrictId && !subDistrict)
-        throw new HttpError(
-          HttpStatus.BAD_REQUEST,
-          "Sub-district cannot be found.",
-          "missing_or_invalid_parameter",
-        );
-      if (body.headOfficeId && !branch)
-        throw new HttpError(
-          HttpStatus.BAD_REQUEST,
-          "Head branch cannot be found.",
-          "missing_or_invalid_parameter",
-        );
-    }
+    const [province, district, subDistrict, head] = await prisma.$transaction([
+      prisma.province.findFirst({ where: { id: body.provinceId || undefined } }),
+      prisma.district.findFirst({ where: { id: body.districtId || undefined } }),
+      prisma.subDistrict.findFirst({ where: { id: body.subDistrictId || undefined } }),
+      prisma.branch.findFirst({ where: { id: body.headOfficeId || undefined } }),
+    ]);
+    if (body.provinceId && !province)
+      throw new HttpError(
+        HttpStatus.BAD_REQUEST,
+        "Province cannot be found.",
+        "missing_or_invalid_parameter",
+      );
+    if (body.districtId && !district)
+      throw new HttpError(
+        HttpStatus.BAD_REQUEST,
+        "District cannot be found.",
+        "missing_or_invalid_parameter",
+      );
+    if (body.subDistrictId && !subDistrict)
+      throw new HttpError(
+        HttpStatus.BAD_REQUEST,
+        "Sub-district cannot be found.",
+        "missing_or_invalid_parameter",
+      );
+    if (body.headOfficeId && !head)
+      throw new HttpError(
+        HttpStatus.BAD_REQUEST,
+        "Head branch cannot be found.",
+        "missing_or_invalid_parameter",
+      );
 
     const { provinceId, districtId, subDistrictId, headOfficeId, ...rest } = body;
 
+    const year = new Date().getFullYear();
+
+    const last = await prisma.branch.findFirst({
+      orderBy: { createdAt: "desc" },
+      where: { headOfficeId: headOfficeId ?? null },
+    });
+
+    const code = !headOfficeId
+      ? `HQ${year.toString().slice(2)}${+(last?.code.slice(-1) || 0) + 1}`
+      : `BR${head?.code.slice(2, 5)}${(+(last?.code.slice(-2) || 0) + 1).toString().padStart(2, "0")}`;
+
     const record = await prisma.branch.create({
       include: {
         province: true,
@@ -200,6 +207,7 @@ export class BranchController extends Controller {
       },
       data: {
         ...rest,
+        code,
         isHeadOffice: !headOfficeId,
         province: { connect: provinceId ? { id: provinceId } : undefined },
         district: { connect: districtId ? { id: districtId } : undefined },