Almost 700 thousand people are waiting for treatment in public hospitals.
The figures from the National Treatment Purchase fund for July represent an increase of nearly 9,500 on the previous month.
The bulk of patients, 493,780, are waiting to be seen by a consultant for the first time at an outpatient clinic.
University Hospital Waterford has the second longest waiting list in the country after Galway University Hospital.
UHW has 36,367 people waiting on outpatient waiting lists, with a further 5,999 people waiting for an inpatient or day case procedure.
The specialties with the biggest waiting lists for inpatient or day case procedures at UHW are Ophthalmology with 2,526 people waiting, followed by Urology with 1,397, Otolaryngology (ENT) 671 and Cardiology 313.