Nearly one million unsold London 2012 Olympics tickets will go on sale on 11 May, with priority given to people who were unsuccessful in both the first two ballots.
Twenty thousand people will be given a 31-hour exclusive window starting at 11am in which to purchase up to four tickets for any event.
After the window closes, the one million people who applied in the initial ballot but were unsuccessful will then have an exclusive five-day sales period to get tickets.
Those eligible for the sales will be contacted by email by London 2012 organisers (Locog).
Tickets for events such as beach volleyball and the opening and closing ceremonies are still up for grabs.
For the first time, 70,000 Olympic Park tickets will go on sale which will allow access to the park to watch some sports on a large screen.
The tickets for events that will be released after the first-priority window has been closed are:
May 13 from 11am - Hockey, Tennis, Wrestling (Freestyle), Wrestling (Greco-Roman), Beach Volleyball and Football
May 14 from 11am - Athletics (Race Walk), Athletics (Marathon), Canoe Slalom, Canoe Sprint, Shooting, Swimming, Volleyball, Weightlifting and Cycling (Track)
May 15 from 11am - Equestrian (Dressage), Equestrian (Eventing), Equestrian (Jumping), Diving, Synchronised Swimming, Handball, Table Tennis, Swimming (Marathon) and Water Polo
May 16 from 11am - Basketball (North Greenwich Arena sessions), Badminton, Sailing, Gymnastics (Artistic), Gymnastics (Rhythmic), Gymnastics (Trampoline), Judo, Taekwondo, Boxing and Fencing
May 17 from 11am - Archery, Basketball (Basketball Arena sessions), Cycling (BMX), Cycling (Mountain Bike), Cycling (Road), Modern Pentathlon, Rowing, Triathlon and Olympic Park tickets
Sebastian Coe, chairman of Locog, said: "We know thousands of sports fans were disappointed when they missed out in the initial sales period because of the massive demand for tickets.
"We promised we would prioritise these fans when we released the contingency tickets, which is exactly what we are doing."
Tickets for the Paralympic Games will go on sale from 11am on May 21 - 100 days before their opening ceremony.