The patients had not finished receiving their treatments.
In May, 12% of patients walked away from the emergency department in Naas General Hospital without finishing their treatment.
There's big variations, but the highest was nearly 18% in Tallaght University Hospital in Dublin.
While almost 10,000 patients walked away from emergency departments across the country.
The figure in St James's Hospital in Dublin was also over 12%.
It's one in every 13 patients who presented at an ED during the month.
These new figures show 9727 people left emergency departments without completing their treatment in May.
That's 7.7% of all presentations at EDs, however, eight hospitals had rates of less than 5%.
The HSE has said Emergency Departments are for people with serious injuries or illnesses, but many others go there when they do not need to.
It said patients are treated by priority and, because of that, some patients with less serious needs may choose to get healthcare elsewhere.