With your Surface Duo 2 closed and the triple lens rear-facing camera facing up, insert the SIM ejector tool into the small hole on the bottom of the left screen, and then gently press in to eject the SIM card tray. Gently pull the SIM tray out to find the serial number on the inside of it.

On a Windows 10/11 PC: Select Start , then select Surface in the all apps list. Select Surface Headphones or Surface Earbuds > Device information. The serial number is listed there.




Microsoft Surface Serial Number Lookup