Third-party repairs will not automatically void the iPhone warranty.
Apple is changing its repair policy regarding third-party providers in the US and Canada. The company has issued a memo to its distributors in North America, saying that phones with display repairs will qualify for warranty coverage if the issue is not related to the display itself.
So, if you have a phone suffering from a hardware issue not covered by Apple, you could send the phone to a third-party company, pay for the service and then still have an iPhone in warranty. Apple demands that such devices must have been repaired while in standard 1-year warranty.
For those who have out-of-warranty phones, Apple Authorized providers can still offer a repair based on the pricing, while you can accept or deny the offer.
However, if a third-party company breaks your iPhone, Apple won’t replace it with a new one, neither it will repair it for free. Problems in battery, display, logic board, and other parts of the phone undergone any third-party repair may also make your iPhone out of warranty.
Apple is initially changing the repair policy is the US and Canada, but other countries may follow soon.