Do you have to get an appraisal to get a loan modification?

No an appraisal is not necessary. A loan modification is not about the value of your home. Instead, it is about "affordability" of your mortgage payment. So youy only really need to prove that you can no longer afford your current mortgage payments and that your house is in danger of entering foreclosure. However, it just so happens that most people needing mortgage loan modifications are upside down on their houses too.