The 30-second check
Dial *#06# on your phone. If an EID number appears alongside your IMEI, your phone has eSIM hardware.
On iPhone
Go to Settings → Cellular (Mobile Data). If you see "Add eSIM" or "Add Cellular Plan", your device supports eSIM. iPhone XR/XS and newer all support eSIM.
On Android
Go to Settings → Network & Internet → SIMs and look for "Download a SIM" or "Add eSIM". Most Samsung Galaxy S20+, Google Pixel 3+ and recent flagships support eSIM.
Two more things to verify
Your phone must be carrier-unlocked to use a travel eSIM, and devices sold in mainland China (and some in Hong Kong) may lack eSIM support even on models that have it elsewhere. See our full supported device list on the Devices page.