The Open returns to Northern Ireland for the first time since the performance of the event in 1956 at Royal Portrush.
15,000 tickets are available for the Open Championship at Royal Portrush in July.
The R & A has extended the capacity at each of the four championships by 3,750, which means that 43,750 spectators will be present at the Co Antrim location every day.
This means that 215,000 spectators will attend the championship during the week, as Northern Ireland organizes the Open Days. for the first time since 1951.
The extra tickets for the 148th Open go on sale on April 15.
The original bench with tickets for the event, which takes place from July 18-21, was sold in record time.
"From the moment tickets and hospitality packages went on sale last year, it was clear that there was a big demand from fans to attend this historic occasion," said Martin Slumbers, president of the R & A.
"We have worked closely with government agencies, advisors and contractors to assess whether we could receive fans every day and have decided that we can do this without affecting the excellent viewing experience."