Injections of the Oxford/AstraZeneca vaccine start in Northern Ireland GP practices on Monday.
A batch of 50,000 doses has been allocated, and those aged over 80 will be prioritised initially.
The country has moved to accelerate delivery of the jab as the pace of the pandemic has picked up.
The new and more infectious variant of Covid-19 has been detected in Northern Ireland.
The number of coronavirus infections has increased rapidly.
Chief medical officers across the UK have decided to delay delivery of the second shot of vaccines.
The intention is that the maximum number of people receive their first jab, with its partial protection, as quickly as possible to help stem the tide of cases that threatens to overwhelm the health service.
Northern Ireland is in the second week of a six-week lockdown in which non-essential retail is closed.
The country has recorded a further 1,662 cases of Covid-19.
A total of 11,810 people have tested positive in the past seven days, the Department of Health said on Sunday.