Plymouth are the only Championship side definitely through to round six, with West Bromwich Albion among six clubs waiting on the outcome of replays.
Also certain of a place are Chelsea, Watford, Manchester City and Tottenham.
Live coverage of the draw is on BBC Two, BBC Radio Five Live, the BBC Sport website and on Ceefax. Matches will take place on 10 and 11 March.
The draw itself will be performed by England coach Steve McClaren and his assistant Terry Venables.
Draw numbers:
1 Chelsea
2 Watford
3 Manchester City
4 Plymouth
5 Manchester United or Reading
6 Arsenal or Blackburn
7 Middlesbrough or West Brom
8 Tottenham
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Replays:
Tuesday, 27 February 2007
Reading v Man Utd, 20:05
West Brom v Middlesbrough, 20:00
Wednesday, 28 February 2007
Blackburn v Arsenal, 20:00