Transferring Data from iPhone 12 to iPhone 16

JFC6491 wrote:

After automatically transferring the info on old iPhone 12 to new iPhone 16,

is the old phone wiped clean? It appears to be, but just wanted to make sure

No, you would need to do this What to do before you sell, give away, trade in, or recycle your Mac - Apple Support

JFC6491 wrote:

The question was in respect of iPhone not an iMac

When I was setting up my new iPhone 16, I was instructed to hold the new phone near to the old one to transfer everything. When this was completed my old phone did not appear to have any details or info left on it.

When I tried to open the old phone it presented itself as if it was starting from scratch - choose language etc

It doesn’t appear to have retained any info.

Sorry this was the link I meant to post What to do before you sell, give away, or trade in your iPhone or iPad - Apple Support .

did you choose the option to erase the old phone after it transferred the data over?