Organizers of the ASB Classic announced the entry of the 23-time major winner on Tuesday.
The 37-year-old Williams has played the hard court tournament once before, losing in the second round in 2017.
On that occasion Williams' experience of the Auckland tournament was not a happy one. She complained about the wind and cold weather, saying "it's my least favorite conditions I've ever played in."
Williams announced her engagement to fiancee Alexis Ohanian during her stay in Auckland and told reporters on Tuesday her memories of the city are "amazing."
"Oh man, I want to win that title so bad," Williams was quoted as saying. "Last time I was there I had so much going on and although I fought through to win my first match, I know I didn't play to my level.
"I have such amazing memories that are really special to me from Auckland. I would really like to add some on court memories to that list."
Williams' preparations for the upcoming U.S. Open have been hampered by injury. She withdrew from Cincinnati last week, citing the same back injury that forced her to retire from the Rogers Cup final in Toronto