Can an oral promise made when signing a written contract be enforced?
Once people reduce an agreement to a signed writing, any evidence of prior or contemporaneous agreements (such as an oral promise) is generally inadmissible in court if it contradicts or materially alters the written contract. Example: You are signing a commercial lease to acquire office space, and ask your landlord to install new carpeting before you move in. If the landlord says “sure” but the contract says you are accepting the office suite “as is”, your claim of the landlord’s promise to install new carpeting would not even be heard in a court of law. Although you could try to show that the landlord fraudulently induced you to sign the lease based on new carpeting, proving fraud is extremely difficult. Moral of the story: if there is to be a written agreement, be sure it includes all verbal promises.