It is important to note that Voice/SMS capabilities are in Beta and your FlexiFone number is intended to be used as your Secondary / Backup number. Voice/SMS service is just an add-on to our Data-Only plans and you must not use this SIM as a replacement to your Primary mobile number (where you would regularly make or receive Calls/Texts on a daily basis) in order to comply with permanent Roaming regulations.
Things to Keep in Mind
No Voicemail or WiFi Calling: These features are not supported due to the nature of the SIM being Multi-Network and not linked to one specific carrier.
No Shortcode, Premium Numbers or Special Numbers: Calls and SMS to shortcodes, premium-rate numbers, and special numbers (NHS 111, etc.) may not be supported or blocked as the called party will view this SIM as a Virtual Number on a Roaming SIM. Freephone numbers (e.g., 0800) will be deducted from your allowance. This is because your SIM technically operates as roaming within the UK.
VoLTE is currently in Beta and is available on EE, O2, Three but not Vodafone. As this is a Roaming SIM, the Voice Quality and overall reliability will not be as great as what you get from a local UK SIM card.
2FA Authentication OTP Codes from certain banks and other providers may be delayed or blocked in rare cases. For delayed SMSs, this may resolved by switching between networks manually (in order to trigger a new network registration).
Limited Destinations: Voice/SMS capabilities are currently supported in the UK, EU and a very few ROW destinations to comply with local Roaming regulations. In all other destinations, your SIM will function as a Data-Only SIM but you may be able to receive incoming SMS.
Device-Related Compatibility: While almost all devices (Apple, Samsung, Huawei, etc.) support 5G and VoLTE with FlexiFone SIM, certain devices like older Google Pixel 4,5,6,7 do not support VoLTE on our SIMs.
Important Note: In rare occasions, if your Incoming calls or SMS are not being received, you may need to manually switch between networks to trigger a new network registration, which will resolve any errors. Please refer to the manual network selection guide here