How do I know if my phone will work with a Japan eSIM and is unlocked?

To use a Japan eSIM, your phone must support eSIM technology and be carrier‑unlocked. Most flagship smartphones released since 2018 meet these requirements, but some budget models do not. You can usually confirm eSIM support in your phone’s settings or by checking the manufacturer’s website. If your phone was purchased through a carrier, contact them to confirm it’s unlocked before you buy a Japan eSIM.