Tributes have poured in for the comedian and actor, whose career spanned decades and made him one of the most recognisable figures in Irish entertainment.
He was born in Cork city on November 21, 1929. From singing in the Opera House as a boy, Mr Tóibín went on to roles in Ryan's Daughter, Bracken, Brideshead Revisited and The Irish R.M.
He was also a stalwart of the Irish theatre scene. In 2010, he was honoured with a Doctor of Arts degree from UCC and was awarded an IFTA Lifetime Achievement Award in 2011.
In 2015 he was bestowed with the Freedom of the city of Cork in a ceremony in City Hall. Mary Shields, then-Lord Mayor of Cork City, said he would be greatly missed.
"He was a very good man, a gentleman, and a great Cork star," she told The Echo. "He wasn't just a Cork star though, he was a national and international star too."
"I got a call when I wasn't long in the job [of Mayor] from the Arts Council of Ireland, who asked would we consider giving the Freedom of the City to Niall. I said to them, you mean to tell me he hasn't already got it?
"He was unique. He was from an Irish-speaking family from the northside of Cork, and he was a very proud Irish man.
"He was so grateful to receive the Freedom of Cork. He said it was the best accolade he ever received. His family rang me afterwards to thank me.
"It was important to recognise him for the wonderful entertainer he was, and how much joy he brought to us all."
President Michael D Higgins, who is in Cork today, also paid tribute to the entertainer.
“It is with great sadness that I have learned of the death of Niall Tóibín," he said. "His contribution to Irish theatre was a unique one, in both Irish and English.
"The range of his work was vast and included unforgettable performances in all of the Irish theatres and some of the most important theatres in London and New York.
"While a huge audience will have adored his comic genius, his work included all the genres – stage, television, film and radio. To the latter he brought a distinctive voice which made him a much-loved interpreter of Irish life and its challenges.
"Sabina and I send our deepest condolences to his children and the other members of his family, and to all those who so loved his work.”
Mr Tóibín is survived by his children Sean, Muireann, Aisling, Sighle and Fiana and his seven grandchildren.
His wife, Judy, passed away in 2002.