It's after a deal with Romania was finalised today.
Confirmation of the extra Pfizer doses comes as the country expects to administer its sixth millionth vaccine this week.
Over the weekend, 30,000 people attended walk-in vaccination centres to receive their first dose.
The HSE's National Lead for the Vaccination Programme, Damien McCallion, says these centres may open again due to the weekend success:
"So overall look, we're very happy with it. It was a good initiative and as I say alongside the registration system, alongside other GPS and pharmacists who continue to offer the vaccine as well it has worked very well over this weekend."
