The deadline for late CAO applications is 5.15pm this evening but potential applicants are advised to register well in advance of that time.
People are also advised to use a demo application in the online handbook before completing the real submission.
Today's deadline is extremely important one but once people submit before 5.15pm, most applicants will be able to add in or amend their course choices via the Change of Mind facility - which opens on May 6 at 12pm - however some restrictions apply.
Mature applicants and those wishing to apply for a restricted course may experience those restrictions when using the Late Application or Change of Mind facilities.
Details of those restrictions are available in the CAO Handbook and on the CAO website.
Anyone making an application today should read that handbook first before filling in their submission.
Once the process has been completed, all successful applicants receive a CAO application number and personal information will appear on screen.
They should also get an email confirmation.