If your friend is in the US & has been covered by employer-provided insurance, he should also be covered by the HIPAA laws & should be able to look at COBRA or conversion coverage, regardless of why he’s leaving his old job. Next, most insurance companies that offer individual policies have specific underwriting guidelines for how recently, & how, pre-existing conditions have been treated to decide whether to apply a pre-existing condition exclusion & for how long. If your friend’s depression was treated more than a year ago, then it’s probably a non-issue. If it’s more recently, he may just be subject to a pre-existing condition exclusion for some period of time. Some companies also “rate up” (read: raise) their premiums for people who have pre-x exclusions but it’s typically not a huge increase. I’d suggest he look into HIPAA & get prices from a few different insurance companies to find the best deal. If he’s in the US, he’s not uninsurable – it just may be more than he’s willing to pay.