You’ll need to register your AppleCare Protection Plan only if you purchase the plan and your covered product separately, or if you purchase your hardware from a reseller who does not automatically register the plan.
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Your AppleCare Protection Plan and AppleCare+ coverage starts from your hardware purchase date. There are many benefits to registering your AppleCare Protection Plan as soon as you purchase it.
Can I purchase the AppleCare Protection Plan anytime?
You can purchase the AppleCare Protection Plan anytime within the one-year limited warranty period. Your eligibility for coverage under the AppleCare Protection Plan starts from your hardware purchase date. Apple strongly recommends that you purchase the AppleCare Protection Plan when you purchase your Apple product to maximize the additional benefits provided under the plan.