Up to 40,000 doses of Covid-19 vaccine could be administered every week at the SSE Arena mass vaccination centre.
The centre in Belfast is planned to open on 29 March, according to the director of the South Eastern Trust's vaccination programme.
Roisin Coulter said these numbers will increase by May.
Ms Coulter said it was expected that everyone in NI will have been offered a first dose by mid-summer.
Last week, Health Minister Robin Swann announced the arena would be used as a mass vaccination site for NI's adult population, with the expectation it would open in April for people aged 60 and under.
Regional centres and GP clinics will still offer vaccines.
Since April 2020, the SSE Arena car park has also been used as a mass testing facility.
"We're confident that we can open the SSE Arena on the 29th of March," Ms Coulter told BBC News NI's Good Morning Ulster on Tuesday.
Ms Coulter currently operates 18 vaccination stations at the Ulster Hospital, but said the SSE Arena move "will enable us to go up to 60 stations".
The plan is for this to operate seven days a week, between 12-14 hours a day.
"We will be able to administer up to 40,000 doses of the vaccine every week," Ms Coulter continued.
"We will staff it in a twin track approach, from all of our existing experienced vaccinators and support teams from the South-Eastern Trust and then we are already working actively to try and draw in as many people as possible from the health and social care public workforce appeal."
People who received a first dose of the vaccine at the Ulster Hospital should return there for a second dose, she added.
From mid-May the plan is for the service to fully move to the SSE Arena where it is hoped "we will really push the numbers up".
"All our vaccination slots are full in the Ulster Hospital vaccination centre and we're doing 1,200 a day, so going by that I would expect the level of interest to be constant and to fill the available slots."
People will be able to book their vaccine online and since Monday the programme has been extended to 60 to 64 year olds.
"You don't have to come from Belfast, in fact anyone in Northern Ireland at the minute can book onto any of the centres across the province," Ms Coulter added.