diff --git a/package.json b/package.json
index 8eb40b2..9339fb7 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "app-ts",
-  "version": "2.0.3",
+  "version": "2.0.4",
   "description": "",
   "main": "dist/server.js",
   "scripts": {
diff --git a/src/__tests__/nas-project-folder.test.ts b/src/__tests__/nas-project-folder.test.ts
index 192c363..c342c25 100644
--- a/src/__tests__/nas-project-folder.test.ts
+++ b/src/__tests__/nas-project-folder.test.ts
@@ -68,3 +68,39 @@ describe("NasFileManager.createProjectFolder", () => {
     );
   });
 });
+
+/**
+ * Folder deletion primitive used by the "delete folder" checkbox on both the
+ * order delete (orders.service deleteOrder) and project delete (projects.service
+ * deleteProject) paths. Matches the project by number prefix.
+ */
+describe("NasFileManager.deleteProjectFolder", () => {
+  let tmpBase: string;
+  let nas: NasFileManager;
+
+  beforeEach(() => {
+    tmpBase = fs.mkdtempSync(path.join(os.tmpdir(), "nas-del-"));
+    nas = new NasFileManager(tmpBase);
+  });
+
+  afterEach(() => {
+    fs.rmSync(tmpBase, { recursive: true, force: true });
+  });
+
+  it("removes an existing project folder (matched by number prefix)", async () => {
+    nas.createProjectFolder("26710010", "Hala");
+    expect(fs.existsSync(path.join(tmpBase, "26710010_Hala"))).toBe(true);
+    const ok = await nas.deleteProjectFolder("26710010");
+    expect(ok).toBe(true);
+    expect(fs.existsSync(path.join(tmpBase, "26710010_Hala"))).toBe(false);
+  });
+
+  it("is a no-op (returns true) when no folder exists for the number", async () => {
+    expect(await nas.deleteProjectFolder("26710011")).toBe(true);
+  });
+
+  it("returns false when the NAS base is not mounted", async () => {
+    const missing = new NasFileManager(path.join(tmpBase, "nope"));
+    expect(await missing.deleteProjectFolder("26710012")).toBe(false);
+  });
+});
diff --git a/src/routes/admin/orders.ts b/src/routes/admin/orders.ts
index c029650..601999d 100644
--- a/src/routes/admin/orders.ts
+++ b/src/routes/admin/orders.ts
@@ -310,7 +310,9 @@ export default async function ordersRoutes(
       const id = parseId(request.params.id, reply);
       if (id === null) return;
 
-      const result = await deleteOrder(id);
+      const body = request.body as Record<string, unknown> | undefined;
+      const deleteFiles = !!body?.delete_files;
+      const result = await deleteOrder(id, deleteFiles);
       if ("error" in result) return error(reply, result.error!, result.status!);
 
       await logAudit({
diff --git a/src/services/orders.service.ts b/src/services/orders.service.ts
index 2afeb74..6d38f29 100644
--- a/src/services/orders.service.ts
+++ b/src/services/orders.service.ts
@@ -588,15 +588,17 @@ export async function updateOrder(id: number, body: UpdateOrderData) {
   return { data: { id, order_number: existing.order_number } };
 }
 
-export async function deleteOrder(id: number) {
+export async function deleteOrder(id: number, deleteFiles = false) {
   const existing = await prisma.orders.findUnique({ where: { id } });
   if (!existing)
     return { error: "Objednávka nenalezena", status: 404 } as const;
 
-  // Fetch linked projects before the transaction for number release later
+  // Fetch linked projects before the transaction for number release and
+  // (optional) NAS folder cleanup later. project_number is needed to locate
+  // the folder on the share.
   const linkedProjects = await prisma.projects.findMany({
     where: { order_id: id },
-    select: { id: true, created_at: true },
+    select: { id: true, created_at: true, project_number: true },
   });
 
   // Guard: projects may have non-cascaded warehouse refs (sklad_issues,
@@ -662,6 +664,24 @@ export async function deleteOrder(id: number) {
     await tx.orders.delete({ where: { id } });
   });
 
+  // Best-effort NAS folder cleanup for the order's project(s), outside the
+  // transaction and only when the user ticked the "delete folder" checkbox in
+  // the order delete modal. Non-fatal: a NAS error must not undo the
+  // already-committed DB delete. deleteProjectFolder is idempotent — it returns
+  // true (no-op) when the folder is already absent.
+  if (deleteFiles && nasFileManager.isConfigured()) {
+    for (const p of linkedProjects) {
+      if (!p.project_number) continue;
+      const ok = await nasFileManager.deleteProjectFolder(p.project_number);
+      if (!ok) {
+        console.error(
+          "[orders.service] NAS folder not deleted for project",
+          p.project_number,
+        );
+      }
+    }
+  }
+
   const year = existing.created_at
     ? new Date(existing.created_at).getFullYear()
     : new Date().getFullYear();