Hastings began her track career at a very early age and made a first place win at the USATF Junior Olympics in the 400 metres in the Youth Girls division. She attended A. Philip Randolph Campus High School in Harlem, New York, where she was able to take her track and field interest to a more competitive level.
Hastings attended the University of South Carolina to work under Curtis Frye. There, Hastings started to become known as “the 400M Diva” after accidentally describing the ladies track team as the “Gamecock Divas” in honor of the school’s mascot, the Gamecock. After coming back from a key injury, 2007 was considered Hastings’ breakout year. Hastings went home to New York for the New Balance Collegiate Invitational and won the 400 m race in 51.70, a personal record at the time, and anchored the 4 × 400 m to a win with the fastest collegiate time for the year. Also in 2007, she won the SEC Championships by running a 50.84. Hastings went on to win the NCAA Championship title and her time in the 400 m at 50.15 was the second fastest time ever on the collegiate level and she had successfully competed undefeated all season becoming the Indoor and Outdoor 400 m champion.
In 2008 at the age of 22, Hastings made the USA Olympic Track and Field Team. She won an Olympic Gold Medal in the Women’s 4 × 400 m relay team by running a 49.97 split in heat two at the 2008 Summer Olympics, where the United States won their heat in 3:22.45 with the team of Mary Wineberg, Monique Henderson,Hastings, and Sanya Richards-Ross. Hastings was replaced in the final by Allyson Felix as the U.S. won gold in 3:18.54. Athletes who run in the heats for medal-winning teams are awarded a medal.
In 2013, Hastings made the USA World Moscow Track and Field Team. She won the USATF 400 meters outdoor title in 49.94 on 22 June 2013.
Natasha Hastings made the US Olympic team for Rio 2016 after coming in third in the US trials with a time of 50.17 for the 400M
She is the cousin of Trinidadian and Tobagonian former footballer Shaka Hislop.
At the 2016 Great North City Games in the UK, Hastings ran a personal best 16.67 150m straight track race, finishing second.