I am a self employed contractor with 3 years left on my contract with a business that has been sold. Does the new owner have to honor my contract?

Depends.  When you say the business was sold, do you mean the entity owning the business (e.g. the stock in a corporation) or the assets of the business?  If the entity was sold, the entity is still obligated under the contract.  Thus, if you had an employment agreement with x corporation owned by John Smith, and Smith sold the stock in x corporation to Jane Doe, x corporation is still under contract with you, even though it is now owned by another person.  If instead, however, x corporation sold its assets to Jane Doe, who did not expressly assume any liabilities, x corporation remains obligated under the contract, but Jane Doe has no obligation. I just want to make clear that, while the contract is still in force, it may very well provide that your employment is terminable at will, or terminable upon sale of the business, or some similar provision.  Thus, the contract may not create any obligation to you.