Dani,

Yes, if you are applying for insurance, you need to reveal any pre-existing conditions. Also, if you expect the company to pay a bill, they do have access to any medical information relevant to that bill.

If a person who has insurance chooses not to turn in an expense, there is no need to tell the insurance company. An individual contract might set such a requirement but, unless the contract so specifies, there is no general requirement to tell.

If I back my car into a tree, I don't have to tell my car insurance company about it. Depending on the cost of the repair, the amount of cash I have on hand, and the chances that turning in the repair bill would substantially increase my premium, I might decide to turn it in, or I might decide not to turn it in and just pay the repair bill myself. This is no different.

Kent