Charles Dickens describes, in the opening of the novella, that Ebenezer Scrooge's counting house/warehouse is located on Cornhill Street in the city of London, England. A counting house is modernly known as an office used for work, keeping records of transactions, and storing finance books for business. This is where Scrooge works and spends most of his time. It was the business place of Scrooge and his old deceased partner, Jacob Marley (also known as the ghost that first appears to him in chains). In the novel, there are only three known employees: Scrooge, Marley, and employee Bob Cratchit. While the exact type of workplace isn't described specifically by Dickens, the audience knows that there are two rooms: "the Tank" where Cratchit sits and "the counting house" where Scrooge spends his time. The Walking Tours of London is a website that offers insight to every place described in Dickens' novel.

Dickens, Charles. “Charles Dickens’ Christmas Books Including 'A Christmas Carol'.” July 1998, Oxford, Oxford University Press.