It's a critical time for many traders with business groups urging people to shop local in the run up to Christmas.
People will be able to visit gyms, hairdressers and places of worship for the first time in two months, however the advice is still to work from home if possible, and wear a mask outdoors on busy streets.
Health experts are also asking people to stay within their own county and not to mix with other households.
Speaking to RedFM News, Tim Mulcahy from The Chicken Inn at the English Market, says traders are acutely aware of the importance of today's reopening:
"Traders have been starved of trade for the whole year. And there's a great opportunity now to get them back open and back up and running again as safely as possible. I mean it's in everyone's interest to keep people safe and I think that's everyone's intention. Judging by the feedback, I think everybody was happy with what the local businesses had to offer. And they think people will continue with that over the next couple of weeks."
