George Clooney visited the cafe in Edinburgh last month and recorded this video message on a staff members Iphone, pledging the first (Scottish) £5 to the cause and encouraging others to do the same.
"I'm giving five pounds to Social Bite, and I hope you do too" the actor says before placing the note on the counter.
Josh Littlejohn discussed the success of last year's Christmas campaign on Social Bite's YouTube channel: “Last year we asked the public to pay £5 to allow us to open on Christmas day and give local homeless people a place to go for a good meal.
“Our target was to provide 800 meals. We were amazed by the response and received over 36,000 donations from all over the world meaning we not only fed folk at Christmas, we were able to feed them all year round in all five of our shops."
This year Social Bite are not only opening for the homeless on Christmas day but are also sending an envoy of food trucks to refugee camps in Calais, Lesbos as well as the border between Serbia and Croatia.
Scottish outdoor clothing brand Tresspass will match every £5 donation with a hat and pair of gloves, as well as jackets, sleeping bags and tents.
Mr Littlejohn said "It's Christmas time, it's freezing outside. There are men, women and children that are absolutely desperate fleeing from conflict, so this is just about really reaching out a hand of compassion to say we're with you, we're not against you."
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