diff --git a/src/components/admin/admin-users-manager.tsx b/src/components/admin/admin-users-manager.tsx
index df1d0d2..b6273f0 100644
--- a/src/components/admin/admin-users-manager.tsx
+++ b/src/components/admin/admin-users-manager.tsx
@@ -22,6 +22,7 @@ import { Tabs, TabsContent, TabsList, TabsTrigger } from "@/components/ui/tabs"
 import { ROLE_OPTIONS, type RoleOption } from "@/lib/authz"
 
 type AdminRole = RoleOption | "machine"
+const NO_COMPANY_ID = "__none__"
 
 type AdminUser = {
   id: string
@@ -393,10 +394,10 @@ export function AdminUsersManager({ initialUsers, initialInvites, roleOptions, d
   }
 
   const isMachineEditing = editUser?.role === "machine"
-  const companyOptions = useMemo(() => [
-    { id: "", name: "Sem empresa vinculada" },
-    ...companies,
-  ], [companies])
+  const companyOptions = useMemo(
+    () => [{ id: NO_COMPANY_ID, name: "Sem empresa vinculada" }, ...companies],
+    [companies]
+  )
 
   return (
     <>
@@ -768,8 +769,10 @@ export function AdminUsersManager({ initialUsers, initialInvites, roleOptions, d
                 <div className="grid gap-2">
                   <Label>Empresa vinculada</Label>
                   <Select
-                    value={editForm.companyId}
-                    onValueChange={(value) => setEditForm((prev) => ({ ...prev, companyId: value }))}
+                    value={editForm.companyId ? editForm.companyId : NO_COMPANY_ID}
+                    onValueChange={(value) =>
+                      setEditForm((prev) => ({ ...prev, companyId: value === NO_COMPANY_ID ? "" : value }))
+                    }
                     disabled={isSavingUser}
                   >
                     <SelectTrigger>