Simson was the top Briton at the 1996 British Grand Prix, placing third overall with a season's best of . He claimed the second AAA title of his career by beating Shaun Pickering by a margin of 19 cm. He also placed fourth at the London Grand Prix that year. In 1997 his best efforts came indoors. After an indoor career best of in Florida, he won the UK trials to qualify for the 1997 IAAF World Indoor Championships. He failed to follow up on his Commonwealth success, however, and was eliminated in the qualifying rounds of the global tournament. Outdoors he was runner-up at the UK Championships to Shaun Pickering – the contest marked the first time two athletes had thrown over nineteen metres at the competition. This proved to be his last major outing at national level and he retired from professional athletics in 1998.