Fox-Pitt, 46, was placed in an induced coma after falling at the World Young Horse Championships in Lion D'Angers on 17 October. He was treated in France before returning to England last week.
"It is fantastic to be home," said the former world number one.
Fox-Pitt is GB's most successful rider with 20 major championship medals.
His horse Reinstated was unharmed in the incident in western France.
Fox-Pitt added: "It feels like a long time away from my family. I would like to thank all the doctors in France, and the rehab team in Poole General Hospital have been incredibly thorough.
"The team at home have been doing an amazing job keeping everything going, but luckily everything is quiet as the horses are all on their end-of-season break. I am looking forward to making a full recovery over the winter."
A statement from British Eventing added: "William has made good progress with his recovery and has now been discharged from hospital to continue his rehab at home. The family continue to ask for privacy as William recovers."
British eventer William Fox-Pitt has been discharged from hospital as he continues his recovery following a serious fall in competition last month.