A spokesman for the elections agency said in one case, a first-time voter who lives in the riding of Fredericton York cast her ballot in the neighbouring riding of Fredericton-Grand Lake after polling staff didn't check her address.
"If they had done so they would have determined that she was actually in the neighbouring riding," said Paul Harpelle. "That wasn't done so they processed her as an eligible voter in that riding."
Kris Austin, the leader of the People's Alliance of New Brunswick, lost in Fredericton-Grand Lake by 26 votes and has been granted a judicial recount set for Friday.
Harpelle said the mistake in that riding wasn't noticed until after election day, so the voter didn't get an opportunity to cast a ballot in the riding she was eligible to.
He said Elections New Brunswick sent incorrect voter information cards to five people in the Saint John area and another eight in the Moncton area that directed them to the wrong ridings. They voted in advance polls and 11 of them later cast ballots in the ridings they were supposed to.
"We of course took immediate steps to contact them, give them a chance to vote where they were eligible to vote, and inform the candidates that this error had occurred," Harpelle said.
"I think it's important to note that in each of these cases the number involved in each of the three areas were not of any significance to actually have any impact on the ultimate outcome."
The number of ridings in the election was reduced to 49 from 55, resulting in new boundaries that in some cases divided streets in half.
Harpelle said the mistakes were the result of geographic errors by Elections New Brunswick.
"This going from 55 to 49 created some very dramatic new shapes of ridings and it's not a surprise that there would be potential instances where, due to geographic errors, that these kinds of things could occur," he said.
He said Elections New Brunswick is confident there are no other people who voted in the wrong ridings.
The president of New Brunswick's Progressive Conservatives said the revelations raise more questions about the way the election was handled.
"It's just another reason why we have lost faith in some of the things that have been going on with Elections New Brunswick," Jason Stephen said Wednesday.
"I certainly have lost confidence in some of the things that have transpired."
Elections New Brunswick has been under scrutiny after it said that a two-hour delay in the reporting of election results last Monday night was the result of a software glitch.
Also Wednesday, the Progressive Conservatives were granted their request for a judicial recount in six ridings.
The recounts in the ridings of Saint John East, Saint John Harbour and Shippagan-Lameque-Miscou will be held Thursday while recounts for Charlotte-Campobello, Carleton-Victoria and Fredericton North are set for Friday.