The annual celebrations have been extended and will run between Friday, March 15 to Monday, March 18, featuring the annual parade and free concert in Custom House Square on St Patrick's Day.
Headlining the free concert on March 17 will be X Factor singer Amelia Lily. Also taking to the stage will be David Julien from the BBC's The Voice, folk group Blackthorn and Ulster-Scots group Rightly On. Tir na N'Og Irish Dancers and Ballysillan Highland Dancers will also be performing.
City Hall will host a variety of activities including talks and exhibitions, music workshops, dance, traditional craft demonstrations, children's arts and crafts, and storytelling there'll also be a waste workshop to create a giant shamrock out of waste and recycled materials.
Visitors will also have the opportunity to get up close and personal with a snake and find out more about the creatures which form a central part of the St Patrick story.
As well as showing some of the live rugby and GAA action over the St Patrick's weekend, the big screen at City Hall will show films including classics The Quiet Man and Into the West.
The Ulster Hall will host a ceili with the Cathal McAnulty Ceili band and the McPeake Family alongside singers, musicians and Irish dancers. There will also be a tea dance, music and poetry workshops, and a photographic exhibition, as well as film screenings of The Commitments and Darby O'Gill and The Little People.
St George's Market will have live themed music and family entertainment throughout the weekend as well as Irish dancing.
Belfast Lord Mayor Gavin Robinson said the festival would be a vibrant and exciting time for the city.
He said: "The city is going to be buzzing. The carnival and concert have become an important part of the city's annual celebrations and this year we have even more on offer.
"There really is something for everyone with some fascinating events planned that will explore the story of St Patrick. City Hall will be the focal point but events will be happening at venues across the city and I'd encourage everyone to come along and enjoy the free events on offer."
The concert at Custom House Square is a non-ticketed event and entry will be on a first come, first served basis with gates opening at 12 noon. This year a special 'kids' zone' will be created over at the 'Big Fish' to allow toddlers and younger children to soak up the buzz and atmosphere away from the crowds.