After playing three games for the Heat in the inaugural Australian domestic competition last season, Vettori put pen to paper on Monday as one of the franchise's overseas players, which are limited to two for each team.
"I had a really good time last season. They were a great bunch of blokes led by a top coach in Darren Lehmann and his support staff, which made for a very enjoyable environment to play cricket in," said Vettori.
However, Vettori again appears unlikely to play in any more than three games in 2012-13 given the left-arm spinners's availability for the Big Bash - which runs from December 7 to January 19 - is dependent on his international commitments.
New Zealand have a Twenty20, one-day and Test tour of South Africa from December 18 to January 25 and Vettori is likely to be involved in all but the 50-over matches.
Vettori, who has retired from one-day international cricket yet continues to play Tests for the Black Caps, announced last month he would be available for T20 internationals again after stepping aside in 2011.
Vettori, who has taken 100 wickets in 95 career T20 games at an average of 22.46 and an economy rate of 6.30, says he wants to play in the Twenty20 World Cup in Sri Lanka in September.