It's been over a month since my approval for Invisalign was sent. How long do most insurance companies take to approve?

Hi there,
this is a very good question.
Officially it takes 30 days to hear back form the insurance companies but most insrtuance companies taken longer. I would recommend you call your insurance carrier and follow up with them 2 weeks after filing the claim. They tend to be more responsive to patients then when the dental office is trying to follow up with them.
Good luck!

Most dental insurance companies have a 3 to 4 week turn around time for pre-treatment authorizations.  Be sure to go over the pre-pretreatment authorization and understand what portion of the overall treatment is covered by your insurance company and what is the portion you will have to pay out of pocket.  Typically, insurance companies will pay for only a portion of the overall treatment.  

Thirty days is the typical turn around time for insurance to hold your moneybefore responding to you or the dental office. You are lucky to have ortho coverage, as most patients do not!