Change TextField’s Underline in Flutter
You can also change its color by following ways. Wrap your TextField in Theme and provide accentColor Theme( data: Theme.of(context).copyWith(accentColor: Colors.red), child: TextField(), ) Using inputDecoration property. TextField( decoration: InputDecoration( focusedBorder: UnderlineInputBorder( borderSide: BorderSide(color: Colors.red), ), ), )