Thank you for your question and welcome to Just Answer.
That's kind of like asking "My car doesn't run, how much to repair it?" It all depends on what the exact problem is and how extensive it is. The answer could be as simple as restoring the tooth with a filling or as complicated as needing a root canal, post and core then a crown to restore your tooth back to full function. The cost of the first scenario is between $100 and $200 whereas the second scenario would run you over $2,000 if it is a back tooth. Without more information as to which tooth this is, how large the fracture is and the details of any pain or sensitivity you have, I can not be more specific.
I hope you find this information helpful. If you have any concerns regarding this issue that I have not addressed, please let me know and I will get back to you with more information.
George McKee DDS