The clinics, announced by Health Minister Robin Swann as a major expansion of the vaccination programme, will also offer first and second jabs to all.
New vaccination clinics across Northern Ireland will offer booster jabs to those aged 50 and over, as well as those over 40 who had their second jab six months ago.
The clinics, announced by Health Minister Robin Swann as a major expansion of the Covid-19 vaccination programme, will also offer first and second jabs to all ages.
Following concerns over the spread of the Omicron variant, boosters are now being offered to everyone aged 18 and over, with priority given in order of descending age groups and those at risk.
No cases of Omicron have yet been identified in Northern Ireland so far, but Mr Swann told the Assembly this week that it is to be expected that the variant is already in circulation in the region.
A number of cases of the new variant have already been detected in both England and Scotland.
The Department of Health has advised those who are 50 or over, who had their second dose three or more months ago that they can now receive the booster at a trust clinic or a participating pharmacy, or wait until invited by a GP.
Those aged 40 to 49 are next on the priority list and eligibility will be extended on a phased basis.
Those who are in this age group and received their second jab six or more months ago can also get their booster at a vaccination clinic.
Eligibility for this age group will be gradually widened in the coming weeks, reducing to the recommended three-month interval.
A department statement said: “Vaccinators will work through all adult age groups in a phased way, just as they did in the original vaccination programme earlier this year.
“The updated Joint Committee on Vaccination and Immunisation (JCVI) advice makes clear that boosters ‘will be offered in order of descending age groups, with priority given to the vaccination of older adults and those in a Covid-19 at-risk group’.
“People under 40 who are more vulnerable to Covid are already being prioritised, alongside older age groups.”
The statement continued: “The JCVI’s announcement also says that those aged 18 to 39 will be eligible for a booster when the NHS calls them forward.
“We will call them forward on phased basis in order of descending age groups, as the JCVI has advised.
“We ask that people wait until their age group is called forward.”
The booster programme involves the Pfizer and Moderna Covid-19 vaccines. The booster dose does not have to be same vaccine as the first and second doses.
Most vaccination hubs are offering both walk-in and booked appointments.
Mr Swann said: “Our vaccination programme will continue to pull out all the stops to bring booster doses to all eligible age groups as quickly as possible.
“Our booster programme will now in many ways mirror the primary dose vaccination programme which steadily moved its way down through the different age groups over a number of months.
“We have now delivered more than three million Covid-19 jabs in Northern Ireland in under a year. That is a remarkable achievement by a health system under severe and relentless pressure.”
The minister continued: “I would again urge people not to be put off getting their first, second or booster doses due to concerns or speculation about the Omicron variant.
“It remains very likely that vaccination will continue to protect against severe illness from Omicron as it does against other variants of SARS-CoV-2.
“In addition, our vaccines provide very good protection against the Delta variant, which remains the predominant strain in Northern Ireland at this point.”
Meanwhile, a further two deaths of patients who had previously tested positive for Covid-19 have been reported in Northern Ireland.
Another 1,585 cases of the virus were also notified.
On Tuesday morning there were 341 Covid-positive patients in hospital, of whom 29 were in intensive care.