The BAFTA winning actress was also said to be spotted hanging out with Brand at a food festival last week. However, she has denied having any romantic link with the actor.
"Just had dinner with lovely friends. And yes they're wrong yet again. He's one of my best mates," Smith posted on Twitter, reports femalefirst.co.uk.
Sheridan was previously in a relationship with director Reg Traviss, but she has said that she has never been out on a date.
"I've just filmed a drama called 'Dates', but I don't think I've ever actually been on one," she said.
"I haven't really been swept off my feet. I haven't been asked out, or maybe I would go. Then again, the idea of sitting opposite someone and making chit-chat - that makes me cringe. Everyone is obsessed with linking me up but I'm alright at the moment," she added.