Sophie, 56, and Prince Edward volunteered in the kitchen for the York Road Project at their temporary facility in the HG Wells Conference Centre in Woking on 10 March - which also happened to be the Earl's 57th birthday.
The charity, which provides support and accommodation to those experiencing homelessness in the area, shared photos of the couple's visit on Instagram.
WATCH: Sophie bakes scones in her kitchen at Bagshot Park
The York Road Project said on its website that Edward and Sophie helped to prepare lunchtime snacks for its clients, which included banana muffins, sausage rolls, cheese and onion twists and ginger biscuits.
The couple also helped staff and volunteers to pack the weekly goody bags, which include toiletries and necessities.
Both donned face masks for the visit, with Edward wearing a tartan face covering and Sophie opting for a red floral printed mask.
The charity shared photos from the Wessexes' visit
In a statement on the York Road Project's website, CEO Cherisse Dealtry said: "It was lovely to welcome back the Countess of Wessex to volunteer again and to meet HRH the Earl of Wessex for the first time.
"We are honoured to have both of them come and volunteer with us for the morning and hear about the work we continue to do here in Woking."
The Countess has been volunteering with a number of organisations and charities throughout the lockdowns, and last month, she carried out her first shift as a St John Ambulance Care Volunteer at an NHS Vaccination centre in Greater London.
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