According to the Office for National Statistics (ONS), there were 6,190 suicides registered in England and Wales in 2024.
It remains the biggest cause of death for men under the age of 50 and the rate remains notably higher among males (17.6 per 100,000 people) than females (5.7 per 100,000).
A promotional video for On Your Side features England men’s football captain Harry Kane, F1 driver George Russell and Women’s Rugby World Cup winner Rochelle ‘Rocky’ Clark.
The toolkit will officially be launched at Everton’s Hill Dickinson Stadium, a venue chosen because its construction included a ‘talking bench’ in memory of former player Gary Speed.
Ex-Wales captain and manager Speed, who also played for Leeds, Bolton, Newcastle and Sheffield United, took his own life in November 2011.
Premier League record goalscorer and Match of the Day pundit Alan Shearer, who was a close friend of Speed, is among the athletes to have given their backing to the initiative.
“For me, this is obviously very personal,” said Shearer.
“We can’t always know when somebody is struggling, but we can all be better at asking, listening, and helping someone find the right support.
“You don’t have to be an expert. You don’t have to have all the answers, but I hope that everyone in sport will use the toolkit.”
Prince William said he wants On Your Side to take advantage of sport’s “remarkable ability to bring people together”.
He added: “In moments of need, the right support can make all the difference. We all have the power to help, and that’s why suicide prevention must be an important part of everyday sporting life.”
The National Health Service, the Samaritans and mental health charity Mind were all consulted during the creation of On Your Side.
The Royal Foundation said the project had taken two years to complete and added that, although it was being launched to coincide with World Suicide Prevention Day, the initiative is “not a one-day campaign” and hopes it will have a long-lasting legacy.
If you, or someone you know, has been affected by any of the issues in this article, then support and information is available at BBC Action Line.