Two people in the other vehicle were treated for minor injuries, according to Norfolk Police.
Philip has largely stayed out of the public eye since his retirement in 2017 but has seen driving his car around the royal estate. The Duke is also often spotted on carriage rides through Windsor Great Park.
Philip has made some royal appearances since his retirement, notably attending grandson Prince Harry's wedding to Meghan Markle last May.
Later, reports claimed the Duke was suffering from a broken rib at that occasion. According to The Sun, the Duke had cracked his rib after slipping in the bathtub.
"The Duke is not a fan of showering and prefers to bathe," a source told the paper. "But he’s a determined man and nothing was going to stop him attending nor would he take any kind of walking aid."