"I feel now is the right time to go," Osborne said, "and I'd like to thank so many people, especially Oliver Sherwood who's backed me all the way.
"I'm going to get my teeth fixed now and then open an account with Ladbrokes."
Osborne, one of the most stylish and articulate jump jockeys of the past decade, affirmed that his retirement had not been prompted by his entanglement with the police. After 10 months on police bail he was finally cleared of any wrongdoing last November.
"All that stuff had nothing to do with my decision to go," he said. "Part of me has not been enjoying the job recently.
"Flat racing has always fascinated me and the intention is to give it a go as a trainer. I plan to get started next season although I don't yet know where I'm going to be operating from - that's open to negotiation."
Not many in racing would have tipped Osborne to call it a day before his fellow Lambourn-based riders Richard Dunwoody and Graham Bradley. However, Osborne said: "There are plenty of jockeys who should have given up far earlier than they did but I think some of them were just frightened to. I was determined this wasn't going to happen to me.
"I'm really excited about the future and will not be looking back. I certainly won't miss going to Ludlow on a Thursday.
"There have been plenty of ups and downs and I couldn't have done it all without lots of help - it would have been impossible to have ridden for 14 years.
"Oliver has been wonderful and I can't believe there would be a better trainer to ride for. He's had a difficult couple of years but I hope the yard can come out of it and I wish them all the best."
Yorkshire-born Osborne's intelligence and willingness to learn was always likely to see him become a success as a jockey. He quickly progressed from a promising amateur to the ranks of fully-fledged jockey.
A thumping from Jenny Pitman brought unwanted headlines early in his career, but the pair have long since been reconciled and, somewhat ironically, he is stepping down just a fortnight after Pitman announced her intention to retire.
"There's no connection between her going and me going," Osborne grinned yesterday. "It's pure coincidence."
As his riding career blossomed, Osborne was associated with numerous top-class horses, although he was never to become champion jockey. He rode a record-equalling five winners at the Cheltenham Festival in 1992, notably Nomadic Way and Remittance Man. "There have been a lot of good horses and it would be difficult to say which one sticks out, though I do remember Shadow Leader winning so well at Cheltenham," he said.
Osborne was probably at the height of his powers when suffering a badly broken wrist at Cheltenham in November, 1997. Barely able to lift a spoon for many months, that injury kept him off the course for almost a year and he received a tremendous ovation when riding Coome Hill to victory on his return to action at Ascot last October. The success had added poignancy as the race was run in memory of his good friend John Durkan.
Oliver Sherwood, with whom Osborne had such a fruitful partnership, said: "Jamie was an outstanding stable-jockey. We have always got on well and Jamie was like a brother - he was a great communicator with owners.
"Whatever he does now I am sure he will be a success as he has got a very good brain in his head."
Nicky Henderson, for who Osborne rode Remittance Man, described him as "one of the best jockeys we have seen in a long time".
"He was one of the greatest horseman-jockeys. He really was in the John Francome league at presenting a horse at a fence. He had a wonderful year at Cheltenham when he rode five winners including Remittance Man and it was great to be a part of that."Reuse content