Rugby Football League chief Richard Lewis says he is still confident that Wembley will host the Powergen Challenge Cup final on 26 August.
The Challenge Cup final has been away from Wembley since 1999
Football's FA Cup Final on 13 May has been moved to Cardiff's Millennium Stadium because builders could not guarantee Wembley would be ready.
But Lewis is optimistic he will not have to make alternative arrangements for rugby league's showpiece event.
"We are as certain as we can be it will be at Wembley," he told the BBC.
If Wembley is not ready for the Challenge Cup final, the RFL may struggle to find an alternative venue.
The Millennium Stadium, which has staged the last three finals, may not be available because the Rolling Stones are performing there on 29 August.
Lewis added: "There is no plan B that we would talk about publicly.
"If we need a plan B that is certainly something we could put in place but we wouldn't be selling tickets if we weren't confident.
"We have sold 30,000 tickets and it is something everyone is looking forward to on 26 August. My understanding is it is going to be ready before that."
Other options for the final could include Murrayfield, which staged the 2000 and 2002 finals, or Twickenham, which played host in 2001.
Old Trafford, which has become the annual venue for the Super League Grand Final, is also a possibility.