The former world champion confirmed the news after she suffered a comprehensive defeat to Lucia Bronzetti in her opening match of the year at the Transylvania Open on Tuesday (04.02.25).
Halep said in an emotional interview post-match: "Tonight, I don’t know if it’s with joy or sadness, I think both feelings are Âtrying me but I’m making this decision with my soul.
"I’ve always been realistic with myself and with my body. Where I probably was, it’s very hard to get there and I know what it means to get there. That’s why I wanted to come here today in Cluj to play in front of you and say goodbye.
"Even though my performance wasn’t very good it was still my soul and I’m very glad you came, and I’ll wonder if I’ll come back again. But for now it’s the last time I’ve played here and I don’t want to cry.
"It’s a beautiful thing. I became world No 1, I won Grand Slams, it’s all I wanted. Life goes on, there is life after tennis and I hope that we will see each other again. I’ll come to the tennis here as often as I can and of course I will continue to play – but to be competitive it requires much more and at this moment it is no longer."
Halep won two Grand Slam titles during her career - the French Open in 2018 and then Wimbledon in 2019 - and spent 64 weeks as world number one.
However, the Romanian player was given a four-year ban for two doping offences after she tested positive for a banned substance in August 2022.
She appealed against the ban at the Court of Arbitration for Sport last year and it was reduced to nine months.
Halep made her return to the WTA tour last March but only played six more matches - winning only one - prior to her retirement.