Zara Tindall and her top horse High Kingdom are entered for Rolex Kentucky (27-30 April).
The pair have travelled to the US four-star previously, in 2015, but the horse was injured just before his dressage test so did not compete.
On that occasion, High Kingdom was being tacked up about an hour before his test, when he kicked out in his stable and split the skin on his off hind on the outside of the pastern. It turned out he had penetrated the joint capsule, which had to be flushed under general anaesthetic. He did not compete again that season.
This year, Zara and High Kingdom are also entered for Badminton, a week after Kentucky, but they are 35th on the wait-list, so it would be touch and go whether they will be offered a chance to compete. A horse would not be expected to contest two such demanding competitions just a week apart, so Zara will only start at one of the two events.
There is a second British entry for Kentucky as US-based British rider James Allison has 15-year-old Parker in the line-up. The pair are bidding for their fifth consecutive completion at the event and their sixth in total.
New Zealand rider Tim Price is also flying over for the competition with his Rio Olympic ride, Ringwood Sky Boy.
World number one Michael Jung will start the competition as favourite. He has won Kentucky the past two years on FischerRocana FST, who returns to defend her title. Michael will also ride his 2015 European champion FischerTakinou.
France’s Maxime Livio is also travelling from Europe to Kentucky, his first time at this event. He rides his 2016 Pau winner Qalao Des Mers.
The home side challenge will be led by Rio individual bronze medallist Phillip Dutton, who has three horses entered — Mr Medicott, I’m Sew Ready and Fernhill Fugitive. Buck Davidson also has three rides (Copper Beach, Petite Flower and Park Trader).
Three American horses hold entries to both Badminton and Kentucky, like High Kingdom — Donner (Lynn Symansky), Simply Priceless (Elisa Wallace) and Rise Against (Bunnie Sexton, 13th on Badminton wait-list). Holly Payne-Caravella has withdrawn Never Outfoxed from the Badminton wait-list, but is entered for Kentucky.