The Connacht Branch have taken the step to avoid disappointment to fans showing up on the day.
Connacht's CEO Gerry Kelly explained: "We are happy to take this decision (to make it an all-ticket match) as it should provide a better matchday experience for everyone with smoother entering to the stadium.
Connacht Rugby Season Ticket holders will not be affected by this decision and season tickets still offer the best value to watch Eric Elwood's side, with ten Magners League games, three Amlin Challenge Cup pool ties and the November friendly against Samoa all at the Sportsground.
Connacht Rugby Season Tickets can be purchased from Ticketmaster or from the Connacht Branch Office at the Sportsground on College Road.
Tickets for the Connacht v Ulster game can be purchased directly from Connacht Rugby or from the Ticketmaster website here.