The figures came from Derry City and Strabane District Council, which said that this year's celebrations have been the most successful ever.
Highlights of the event included 'The Rise of the River Gods' parade.
In October, the city was named the world's best Halloween spot in a poll by American newspaper USA Today.
Revellers in Strabane also enjoyed Halloween celebrations with a fireworks display over the River Mourne.
The Mayor of Derry City and Strabane District Council, Councillor Elisha McCallion, said the numbers attending had surpassed all expectations.
"Council pulled out all the stops this year to wow locals and visitors alike with a magnificent Halloween programme over the three day festival which led up to the spectacular carnival parade and fireworks display.
"The 'Rise of the River Gods' theme really captured the public's imagination and, it was fantastic to see people of all ages enjoying the family-friendly atmosphere."
Around 50,000 people attended the Halloween festival in Londonderry and Strabane over the weekend.