Many ins. programs in the US cover everything having to do with the CI, from surgery to equipment and accessories to auditory rehabilitation for a year after (or sometimes more, if there are other learning needs/if late-implanted, if under school age), and the warranty goes into effect on the equipment for 3 years, afterwards, additional coverage may need to be purchased from the implant co. or through homeowners, just like you would cover your computer or a wedding ring 
. Upgrades are also included, and then the warranty starts all over again.
That's been my experience: my daughter has 2 CIs (+ all-upgraded equipment this year). In my state, healthcare insurance is mandatory, so everyone is covered if they are approved for a CI, but perhaps some people have a high deductible or have gone ahead without having hc insurance.
