The Stormont Executive has opted not to impose any new Covid-19 restrictions on Northern Ireland sport despite the recent decisions in Wales and Scotland.
Full crowds can continue to attend Northern Ireland sports events until another review on 30 December.
Guidance will be issued to those travelling to and from sports fixtures - including advice not to car share.
Festive games include Ulster v Connacht in rugby union on 26 December and Monday's Irish Premiership programme.
The Belfast Giants are also in home action against Glasgow Clan on Boxing Day.
Northern Ireland First Minister Paul Givan said that spectators would be urged to take lateral flow tests beforehand in addition to wearing masks at sporting events.
Asked about the different approach taken by the Northern Ireland Executive in comparison with their counterparts in Wales and Scotland, the first minister said that "very clear advice is being given in terms of the kind of mitigations that will all help us".
"We are strongly advising for those events taking place outdoors and indoor seated, to get your lateral flow before you go to those events, to wear a face covering when you go to those events even when it is outdoors and not to be car sharing in terms of transportation," said the first minister.
The Welsh government has limited festive sporting fixtures to 50 spectators from Boxing Day with outdoor events in Scotland allowed a maximum 500 people for a three-week period from 26 December amid surging numbers of Omicron cases.
In the Republic of Ireland, outdoor sporting attendances are limited to 50% of venue capacity or a maximum of 5,000 spectators - whichever is the lower number.
Northern Ireland's nightclubs will be closed from 26 December as fresh restrictions are imposed to tackle the Omicron Covid variant.
Tighter restrictions are likely for all hospitality venues which are expected to include table service and limits on table numbers.
Stormont ministers met for more than four hours on Wednesday before announcing their decisions.