The Backin' Belfast campaign has become one of the most successful "within civic social media" across Ireland, it has been claimed.
Launched six weeks ago, the campaign came as a response by retailers, pub owners and businesses to encourage people back into Belfast amid Union flag protests.
New figures released by the Belfast Visitor & Convention Bureau show that the #backinbelfast message has reached millions of people through social networking sites, including Twitter and Facebook.
In the six weeks #backinbelfast has had 21.6m Twitter impressions – which is the number of people that have been exposed to the message or brand.
It also revealed 3.9m Twitter accounts were reached – an estimated 207,000 on a daily basis.
There were also 17,713 tweets using #backinbelfast and 12,785 Backin' Belfast social media followers.
John Keane, managing director of Ardmore Advertising, said it was welcome news.
"This has been one of the island of Ireland's most successful civic social media campaigns," he said.
"In the first four weeks it achieved more than 20 million Twitter impressions, reaching 10 million Twitter accounts. In that short space of time, there were also an unprecedented 20,000 Backin' Belfast tweets recorded."
He added: "The social media element of the campaign has been trending on Twitter within the Belfast area, making it the most talked-about topic of conversation on the city's social network."
The Backin' Belfast web page has had 105,142 'hits'.
It had been estimated that £15m was lost in trade over Christmas, with some pubs reporting trade down as much as 50%.
The campaign was launched on the back of social media rallying calls for people to reclaim the city –including #Operationsitin.
Aimed at encouraging people back into the city the campaign received £1.5m in support.
Backin' Belfast' secured £600,000 from the Department of Enterprise, Trade and Investment, and Belfast City Council donated £400,000 to the campaign.
And Belfast businesses donated offers and giveaways worth £500,000 to the cause.
The campaign aimed to stimulate growth in the hospitality and retail sector in the city, which employs more than 35,000 people.
An Omnibus survey on the safety/ease of access in and out of Belfast has also revealed that since the campaign began the level of concern about safety in the city –while is still there – has dropped.
In mid-January, 62% of people polled were concerned about safety if coming into Belfast. This has gone down to 47%.
While 26% are still "very concerned" about personal safety, this is down from 36% six weeks ago.
Gerry Lennon, chief executive at the Belfast Visitor & Convention Bureau, welcomed the new figures. "We now have 13,000 followers on Twitter; six weeks ago we had nothing. It feels bigger than a marketing campaign."