How much does it cost to replace iPhone 13 battery?

Here is a calculator for an Apple repair→iPhone Battery Replacement - Official Apple Support. Usually they can do it while you wait or shop.

Apple authorized service providers can charge what they want, and non-authorized providers will not install a genuine battery or warranty it.

There are now so many variants of each Apple product line that many Apple retail stores will not inventory the myriad repair parts variants requred. Check with the store first. Almost all service is now done through Apple's centralized refurbish centers.

The refurbishment center may elect to install a new battery in your phone, or send you a refurbished phone of identical specs. My current iPad is an Apple refurb following a battery service and it is still strong after four years of daily use.

Apple's statement on its refurbed devices: Learn more about each refurbished iPhone.

You can find out on this Apple get support sheet, just fill out the the on screen information

Select your product for to fix- get support

Allan Jones wrote:

There are now so many variants of each Apple product line that many Apple retail stores will not inventory the myriad repair parts variants requred. Check with the store first. Almost all service is now done through Apple's centralized refurbish centers.

The refurbishment center may elect to install a new battery in your phone, or send you a refurbished phone of identical specs. My current iPad is an Apple refurb following a battery service and it is still strong after four years of daily use.

Apple's statement on its refurbed devices: Learn more about each refurbished iPhone.

kittyboxer did not say it was a refurbished iPhone, and Apple stores DO stock batteries for all current models.