Kingsbarns did not race until October 2012, where he easily won a one milemaiden race at Navan Racecourse. Under jockey Joseph O'Brien he beat Risk Return by seven lengths. Having originally not been entered he was supplemented for the Racing Post Trophy at the cost of £17,500. After being supplemented he was priced as big as 8/1 to win the race, but received significant support and started as the 15/8 favourite. Again ridden by O'Brien, he took the lead with over one furlong left to run. He then pulled away to win the race by one and three quarter lengths from the Richard Hannon, Sr. trained Van Der Neer, who just beat Steeler for second place. After the race Joseph O'Brien said: "He relaxed and travelled very well. I might have got to the front too soon but my momentum took me there." After his victory he was made favourite for the 2013 Epsom Derby and second favourite for the 2000 Guineas. In his only two runs as a two-year-old he earned £130,831. In the 2012 European Thoroughbred Racehorse Rankings, he was given a rating of 118, putting him in second place, six pounds below the top-rated Dawn Approach.
2013: three-year-old season
In April 2013, Kingsbarns was ruled out of the 2000 Guineas after failing to recover sufficiently from a foot infection. He made his belated seasonal debut in the Irish Champion Stakes at Leopardstown Racecourse on 7 September. He was settled in fourth place by Joseph O'Brien, but dropped away before the turn into the straight and was pulled up in a race won by The Fugue. Kingsbarns was next entered in the Queen Elizabeth II stakes on British Champions Day at Ascot Racecourse. Racing at odds of 14-1, he ran third behind runaway winner Olympic Glory. After the race, Kingsbarns' trainer Aidan O'Brien said: "I'm delighted with that. It all went wrong for him in the spring and this was like our first run of the season. I'd imagine that will be it for this year and we'll look forward to next season with him."
2014: four-year-old season
Kingsbarns began his third season in the Listed Heritage Stakes at Leopardstown in April. Despite being less than fully fit he was made the 4/6 favourite but finished third of the five runners behind the John Oxx-trained Qewy. The colt was off the racecourse for four and a half months before returning in the Royal Whip Stakes at the Curragh in August, when he finished second, beaten half a length by his stable companion Hall of Mirrors. In September, he was sent to France for the Prix Foy in which he finished fifth of the six runners behind Ruler of the World. On 18 October, Kingbarns ran for the second time in the Queen Elizabeth II Stakes at Ascot. He was among the leaders until the final furlong when he weakened rapidly and finished sixth behind Charm Spirit.
After retirement
Kingsbarns entered South African-based Drakenstein Stud Farm. He died from colic on 16 May 2018.
Pedigree
Note: b. = Bay, ch. = Chestnut * Kingsbarns was inbred 3 × 4 to Northern Dancer, meaning that the stallion appears once in the third generation and once in the fourth generation of his pedigree.
