How much does it cost to replace an IPhone 6 charger port?

Check to make sure there is no debris, lint, or other obstruction in the port. If there isn't, and it is still not working correctly, make a Genius Bar appointment to have the device examined by Apple. They would not repair the charging port, they would replace the entire device. If the device is out of warranty, the out of warranty cost for an iPhone 6 is listed in this link, depending on your location. iPhone Repair - Official Apple Support

Hi

Make an appointment at Apple store For repair / replacement

They may offer you An out of warranty replacement you will need to pay part of the cost.

Or contact Support.apple.com

Cheers

Brian 🇬-1F1E7;