Will I lose my factory unlock if I reset all settings on my iPhone?

Can you define "factory unlock " ( Apple has no such term )

do you mean

you purchased from Apple Retail or Apple online not carrier locked

Your Carrier agreed to unlock the iPhone for you

Or a third party arranged a "factory unlock"

If one or two nothing will change

if three you will relock your iPhone to the original carrier

They just refer to it as "unlocked" not "factory unlocked". Did you buy your iPhone directly from Apple as unlocked? Or, if you are not in the US, did you buy it from a cell provider that offers an unlocked iPhone.

And do remember there is a difference between unlocked and no contract.

AT&T does not sell unlocked iPhones Peter. In the US you can only get them in an Apple Store or online from Apple. Or, if you only need an unlcocked GSM side you can get a full price iPhone 5 from Verizon.

Actually I said

No iphones are locked except a few sold by AT&T

I should have added out of the factory locked where i believe some iPhones were shipped direct to AT&T already locked to AT&T maybe that has now ceased

I am fully aware of the availability of unlocked carriers 😉

but thanks for keeping me on my toes I will always be happy to reciprocate

No.

Please show me a reference to support that.

Allan

No it does not .

No iphones are locked except a few sold by AT&T .The carrier locks them when they process the sale

You haven't answered the question

I breathlessly waiting.😉

There are always bananas out there 😉

However is OP trying to avoid the question what factory unlock ??