United are yet to confirm the number of tickets purchased before the May 15 renewal deadline, but chief executive officer Shaun Harvey described the response from supporters as "extremely encouraging".
"The May 15 deadline has now passed and, as always, there was a flurry of late activity," said Harvey. "We are extremely encouraged by the response which has seen us bank £4.5m, with a further commitment of £1m.
"This gives us a good foundation to work from for the 2005-06 season and we expect to receive further applications, although obviously supporters have now missed the initial discount."