Multi-IMSI
Several IMSIs on one SIM let a device present a local identity per country, but they remain one subscription.
Definitions only — a term explained here is not a service we sell.
Multi-IMSI keeps several IMSIs on one SIM and switches between them, usually by matching the visited network's MCC and MNC against a table. The identity changes; the subscription does not.
Several IMSIs on one SIM
IMSI 1 active
- Device
- eUICC
- Roaming identity IMSI 1
- Subscription
- Device
- eUICC
- Roaming identity IMSI 2
- Subscription
Text description
The device, eUICC, roaming identity and subscription appear as four numbered parts in a row. The roaming identity switches between IMSI 1 and IMSI 2; the subscription does not change.
How the switch works
The SIM carries an applet and a table of IMSIs, each paired with the networks it may use. The applet compares the broadcast MCC and MNC with the table and presents the matching IMSI. A timer or a steering command can also switch.
One subscription, not several
Several IMSIs on one SIM are not several local subscriptions: every identity sits in the same subscription, so the commercial relationship stays with one provider. Confirm the fallback order when no table entry matches. A border crossing can delay the first report while the device scans and attaches, so buffer readings. Permanent-roaming rules still apply. See What is multi-IMSI for the design choices.