FAQs

Phones

What devices are supported?

Please see our Supported Devices page for more information.

How do I know if my phone is locked?

If you live in a country where phone locking is prohibited then your phone is likely unlocked (see our Global Availability page to check the status of your country). Otherwise, there are only two foolproof ways: 1) Insert a SIM from another carrier and make a call. If it works, the phone is unlocked. 2) Contact your current mobile service provider. Our Phone Unlocking Guide links to the unlocking FAQs for common providers.

The following methods work on many devices but are not foolproof:

iPhone: Go to Settings > General > About. If “No SIM restrictions” appears next to Carrier Lock, your iPhone is unlocked.
Android: Go to Settings > Connections > Mobile Networks > Network Operators and tap Search Now. If multiple names show up, your phone is probably unlocked.

Phone locks apply to all SIM slots in the device. It’s not possible to unlock a specific SIM slot.

How do I unlock a locked phone?

This depends on the service provider that initiated the lock. Some will automatically unlock after 90 days of service (good job Verizon!). French service providers must unlock phones for free after 3 months. Most however require you to pay off the remaining balance on the device and then request an unlock. Please see our Phone Unlocking guide for more information on unlocking procedures for common mobile service providers.

Why can’t I make/receive calls on my iPhone

The Extend service leverages Voice over LTE (VoLTE) in order to ensure the highest quality voice experience. iPhones generally enable VoLTE by default but in some cases you must do so manually:

Open the Settings app on your iPhone.
Tap Cellular (or Mobile Service).
If you have dual SIM, select the specific line.
Tap Cellular Data Options (or Mobile Data Options).
Tap Voice & Data.
Toggle the VoLTE switch to ON.

How should my device APN be configured?

If you are using a Supported Phone then APN information will be automatically configured. If you are using a Compatible Phone then you will need to create the following APNs manually:

Phone Data APN

Name: globaldata
APN: globaldata
If your service is enabled for MMS messaging you will need to set the following fields. Otherwise accept the default values for all fields.
- MMS proxy: 37.18.129.98
- MMS Port: 8008
- MMSC: http://mms.mobileuc.global/

Hotspot Data APN

Name: globalhotspot
APN: globalhotspot
APN Type:
- Android 14+: Set to ‘tethering’
- Prior to Android 14: Set to ‘DUN’. Some handsets require full capitalization.

Reboot your phone for added/changed APN data to take effect.

If I pay off the remaining balance on my phone, will I lose promotional discounts my service provider gave me?

This depends on the contract you have with your service provider but it is common practice to retain discounts that you received on the price of the phone and any credits you received for a device trade-in. Please consult with your service provider to understand your specific situation.

My service provider requires me to pay off my phone before they will unlock it. Do I have any other options?

Not really but if you are looking to add Extend as a second SIM in your personal device then you can consider moving your primary (personal) service to another service provider. Service providers often offer promotional deals that include reimbursing you for phone payoff charges to encourage you to switch (e.g. T-Mobile US Freedom offer).

Service

Where can Extend be used?

Smartphone Subscription Plans: Can be used globally but subscribers must reside in one or more of Extend’s Home Countries. There are no roaming fees for usage in Home Countries or Home Away Countries. Usage outside of Home and Home Away Countries is supported via the Day Pass service add-on. When enabled, you will be charged a fixed rate for each twenty four hours of usage. See the Subscription Plans page for more details.
Fixed Wireless Device Plans: Can be used only in Home Countries. Roaming is not supported.

Does Extend support 5G data?

5G data is supported in a majority of our Home Countries and a number of our Home Away and international roaming countries. See our Global Availability page for data speed information per Home Country. If you have a 5G capable device, it will automatically take advantage of 5G speeds when coverage is available.

Is SMS/MMS supported?

SMS is enabled by default when Extend is used in conjunction with a mobile number. SMS and MMS can be optionally enabled for wireline (geographic) numbers in the U.S. only.

How can I prevent roaming charges?

To ensure you don’t incur roaming charges when traveling outside of Home and Home Away Countries, put your device into airplane mode and then reenable WiFi. Alternatively, you can disable mobile data through your phone’s settings and then refrain from making calls, answering calls, or sending text messages while roaming. Receiving inbound text messages does not incur roaming charges.

Can I allocate a new number or port an existing number to use with Extend?

Extend leverages the number already assigned to a subscriber within their UC platform. You can work with your existing number provider for number allocation and port requests. If your number provider is separate from your Extend service provider you will need to contact your Extend provider to inform them of any number changes.

Can I port my employees’ mobile numbers to Extend?

As with allocating new numbers, Extend only supports ‘port ins’ for UK mobile numbers. In the US, most of our resellers support the ability to ‘port in’ US-based mobile numbers to their wireline service. The ported number technically becomes a wireline number but it retains the ability to send/receive SMS/MMS messages and is therefore a mobile number for all practical purposes. In the rest of the world it is not possible to port a mobile number to Extend or a wireline service provider.

How do I obtain an Extend SIM?

This depends on your UC platform and Extend reseller. Some platforms, such as Microsoft Teams and Cisco WebEx Go, provide an eSIM directly via their end user portals (see below FAQs on Teams and WebEx integration). For other UC platforms, your reseller and IT department will collaborate to provide you with an eSIM (normally via email) or a physical SIM.

How do I install an eSIM?

Procedures differ based on the device make and model. See the following instructions for popular devices:

Google Pixel
Samsung
iPhone – The eSIM Quick Transfer option is not supported. Please follow the steps for scanning/clicking a QR code.

Note: If you are subscribed to the 2nd Line (Background Data) plan then you must ensure that mobile data defaults to your other SIM as the Background Data plan only supports data during active calls.

While not required by all devices, we recommend restarting your device after adding a SIM.

What if I need a replacement SIM?

Contact your IT department. They will coordinate with their Extend reseller for a replacement.

If installed as a 2nd SIM, how do I select the Extend line for making/receiving calls and texts?

Procedures differ based on your smartphone make and model. See the following instructions for our currently supported devices:

Why doesn’t call waiting work when I have Extend installed as a 2nd SIM?

Current dual SIM capable devices implement a standard referred to as Dual SIM Dual Standby (DSDS). This standard makes use of a single radio within the smartphone to ‘listen’ for calls on both SIMs. The upside to this approach is a minimal impact to your battery. The downside is you will not receive a call waiting notification on a line (SIM) if you have an active call on the other line (SIM). The exception to this rule is if you have activated and are using Voice over WiFi on one of the lines. Call Waiting will work as usual on a per line basis (i.e. you will receive notification of an incoming call on the same line (SIM) as an active call).

Why can’t I make an outbound call on my Extend line?

Please verify the following. If you are still experiencing an issue, contact your IT department.

Verify that you have a signal on your Extend line. A device restart or entering/exiting airplane mode may help.
For iPhone users, ensure you have enabled VoLTE on your device:
Dual SIM Installation: Go to Settings> Cellular (or Mobile Data in the UK) > [Select the Extend Line]> Voice & Data, Ensure VoLTE slider is On.
- Single SIM Installation: Go to Settings> Cellular (or Mobile Data in the UK) > Cellular Data Options> Voice & Data, Ensure VoLTE slider is On.
- If Extend is being used as a 2nd SIM, ensure you have selected the Extend line for your outbound call (see the selecting Extend line FAQ above)
Verify you are using a supported phone

Why is my UC Voicemail not picking up my unanswered calls?

Check whether you have SPAM filtering enabled via your device (e.g. Call Screen on Pixel devices) or a third party app. Many of these solutions will answer the call in the background and therefore prevent roll over to voicemail.

Does Extend support WiFi Calling?

WiFi Calling is supported in the UK for iOS 18+ devices. We will be adding support for additional countries and devices shortly so stay tuned!

What is WiFi Calling?

WiFi Calling allows you to make and receive calls and texts over a WiFi network. It enhances coverage within buildings and other areas where cellular signals have a hard time penetrating.

How do I enable WiFi Calling?

Procedures differ based on your smartphone make and model. Please see the instructions below. The status bar will indicate when WiFi Calling is active.

How do I use WiFi Calling?

You don’t have to do anything different. Based on your device and its configured WiFi Calling settings, it will choose when to make calls via WiFi and will display ‘Wi-Fi’ as part of the network name in the status bar. You will make and receive calls using the native dialer just like you would with cellular calling. Please be aware, however, that if you roam out of coverage of the WiFi network, any active calls will drop and have to be reestablished. The same is true for calls initiated via the cellular network.

How are WiFi Calling calls charged?

You can use WiFi Calling without incurring additional fees such as roaming charges. Outbound calls will, however, incur the same PSTN routing fees as if the call was placed via cellular (e.g. a call to an international destination costs the same regardless of cellular vs WIFi Calling).

Why don’t I see the WiFi Calling indicator?

Your phone determines when to leverage the WiFi network for calling. Some phones, such as iPhones, will default to using a cellular signal if one is available even if you are connected to a WiFi network. iPhones also have a WiFi Assist feature which will move data connections to cellular if WiFi quality is degraded. You can force your device to use WiFi Calling by enabling Airplane Mode and then re-enable WiFi. If the WiFi Calling indicator is still not visible then please validate your device has an active WiFi connection and that WiFi Calling is enabled.

Is WiFi Calling call quality the same as cellular calls?

WiFi networks do not have Quality of Service (QoS) mechanisms for ensuring voice quality like cellular networks do. You may experience poor audio quality and/or dropped calls if the WiFi network you are attached to is overloaded by other applications or users (e.g. the person next to you at the coffee shop is streaming Netflix).

How do I make an emergency call?

Dial the emergency number for the country you are currently in if you know it (e.g. 911, 112, 999, etc.). Otherwise, dial the emergency number from your home country. This will work in most cases. Your device will either automatically attempt to use a cellular connection or prompt you to make a selection between cellular and WiFi Calling (if enabled). You should always choose to use a cellular connection when available. This maximizes the chance your emergency call will be routed to the Public Safety Answering Point (PSAP) closest to your location, both domestically and while roaming internationally. If no cellular signal is available or you choose to use WiFi Calling, your device will place the emergency call via WiFi Calling (if connected). Emergency calls placed via WiFi Calling are only supported in your home country. All WiFi Calling calls, including those to emergency numbers, will drop if you lose internet connectivity. Your device will automatically provide location information to the PSAP when available but you should be prepared to provide your physical address to the PSAP operator when requested.

Can I send a text to an emergency services number?

Sending an SMS to an emergency number is supported in a limited number of jurisdictions. It is recommended you always place a voice call to receive emergency services rather than texting. If you send an SMS to an emergency number and SMS is not supported, you will receive an error response indicating it wasn’t deliverable.

Are iMessage and RCS messaging supported?

iMessage is fully supported. RCS is supported for mobile numbers and all U.S numbers. RCS is not supported for geographic (wireline) numbers outside of the U.S.

Microsoft Teams Integration

How do I enable Extend for my employees?

Step 1: Provide your Extend reseller with your Teams tenant ID

Step 2: Use the Teams Admin Center to 1) grant employees permission to install the Extend Teams App, and 2) enable the ‘SIP devices can be used for calls’ config item within the Calling Policy assigned to your employees. (Voice > Calling Policies).

Step 3: Provide your Extend reseller with the phone number and email address of each employee you wish to enable (along with service information such as subscription plan, roaming policy, etc.). Extend will automatically send a welcome email to the employee with instructions on how to use the Teams Extend pairing app to install an eSIM and link it to Teams.

Which Teams licenses are required?

Each Teams subscriber must have a Teams Phone license and PSTN number assigned.

How do I associate my Extend SIM with my Teams account?

You will receive a welcome email instructing you to install the Extend pairing app for Teams. Using your Teams application, select ‘Apps’ and then search for ‘Extend’. Click ‘Open’ on the Extend application and follow the on screen instructions that take you through allocating/installing an Extend eSIM and pairing it with your Teams account.

What if I receive an error code during the pairing process?

End User: Contact your IT department. They will ensure your Teams account is configured correctly for Extend (e.g. has a PSTN number assigned to it).

IT Department: Use Teams Admin Center to verify:

The ‘SIP devices can be used for calls’ config item is enabled in the employee’s Calling Policy (Voice > Calling Policies).
A ‘Primary Phone Number’ is set for the employee (Users > Manage Users > [Select Employee])

What if I get an error when using the QR code to install an eSIM during the pairing process?

Try refreshing the QR code using the Extend app. If that doesn’t address the issue, follow the manual installation instructions for your smartphone model (see the ‘how to install an eSIM’ FAQ above).

What if I receive a text indicating I’ve been signed out of my Teams account?

Certain events such as changing your Teams password will result in your Extend device being signed out. If this occurs, go to the Extend app within Teams and follow the on screen instructions to sign back in.

Which Teams features are available for my Extend line?

Teams features automatically invoked by the server (e.g. presence status updates) or manually via the Teams desktop and mobile clients (e.g. do not disturb) are supported. The following additional features may be invoked via DTMF using your phone’s keypad:

Teams Feature	Action
Enable Do Not Disturb	Dial 30
Disable Do Not Disturb	Dial 31
Call Forward Immediate	Dial 33
Call Forward Unanswered	Dial 34
Call Forward Ring Also	Dial 35
Disable Call Forward	Dial 32
Call Move to Extend	Active call on desktop or mobile Teams app Select Transfer Enter your DID Answer the call on your mobile via the Extend line NOTE: The “Busy on busy during calls” setting in the assigned Calling Policy must be set to “Off”.

Why do I receive two incoming call notifications?

Both the Teams mobile app and your phone’s native dialer provide an incoming call notification. To receive only one, turn off call notifications within the Teams mobile app: Profile -> Notifications -> Custom -> Calls.

Why do I not receive calls on my Extend line from Teams contacts that I’ve marked as Priority?

When you set your Teams status to Do Not Disturb, Teams will only allow calls from contacts marked as Priority. At this time, Teams only supports allowing Priority calls through to your native Teams devices (e.g. desktop client, mobile app, etc). Enabling Call Notifications via the Teams mobile app (Profile -> Notifications -> Custom -> Calls) will allow your Extend line to receive priority calls but it will also cause you to receive two incoming call notifications for all calls (one from the Teams mobile app and one from the native dialer).

Cisco Webex Go Integration

How do I enable Webex Go for my employees?

Step 1: Provide your Extend reseller with the phone number and email address of each employee you wish to enable (along with service information such as subscription plan, roaming policy, etc.)

Step 2: Use the Webex Control Hub to add the numbers you provided in Step 1) to your Webex tenant and select ‘mobile number’ as their type. Once added, assign those numbers to the Webex users you wish to enable for Extend.

Note: You can skip this step if you’ve given your Extend reseller authorization to make these changes for you.

Step 3: Once a number is assigned, Extend will automatically send a welcome email to the user with instructions for installing an eSIM via a QR code. Once the eSIM is installed, Extend will be active for the user and linked to their Webex account for calling.

Which Webex licenses are required?

Each Webex subscriber must have a Webex Calling Professional license and PSTN number assigned.

Which Webex features are available for my Extend line?

Webex features automatically invoked by the server (e.g. presence status updates) or manually via the Webex desktop and mobile clients (e.g. do not disturb) are supported. Use the Webex mobile app to initiate hold/retrieve and transfer functionality for active mobile calls or to uplift calls to a Webex video meeting. Use the DTMF keypad to invoke Webex feature access codes.

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