An eSIM (embedded SIM or digital SIM) is a programmable chip built into smartphones that replaces physical SIM cards. Instead of inserting a plastic card, you download a digital profile from eSIM providers to activate cellular service.

For business VoIP, eSIM works by using SIP software built into iPhone and Android phones to register with your voice platform, enabling native dialer calling without apps or dependency on data plans.

The phone connects through the cellular carrier's QoS-engineered network for voice quality while routing calls back to your UC system.

Most modern iPhones and Samsung Android phones support eSIM technology. A detailed compatibility list is available for specific models.

For business eSIM services, the cellular network varies by country – in the United States, AT&T provides the radio access network; in Puerto Rico, Claro operates the network; other countries use different eSIM carriers.

The network profile automatically roams to the correct carrier, but SIP traffic always connects back to your home VoIP platform regardless of location.

eSIM is digital and programmable – you activate service by downloading a profile rather than inserting a physical card. Physical SIMs require shipping, manual installation, and swapping when changing carriers.

For business deployments, eSIM enables faster provisioning, remote activation, and the ability to combine multiple phone plans on multi-SIM devices. However, physical SIMs can still be used if devices don't support eSIM – the service works with both formats.

To get an eSIM, your eSIM provider (ECG in this case) sends a QR code or activation profile. Scan the code in your phone's settings to download the eSIM profile and activate service.

How to transfer eSIM depends on the device – newer iPhones support eSIM transfer via Bluetooth proximity, while older devices require deactivating the eSIM on one phone and reactivating it on another using a new QR code from your eSIM service provider.

Yes, the eSIM business service works in over 20 countries with international roaming. This means you can provide national telephone numbers to users operating in different countries – smartphones connect through the mobile cellular IMS network back to your voice platform.

Users in many countries can roam to others while maintaining their business calling, texting, and UC features through your VoIP system.

Yes, smartphones get data plans to complement voice services. Unlimited plans are available as well as lower-cost plans with limited bandwidth per month.

You can tune the exact feature package to balance cost and functionality for your business eSIM deployment, providing e sim plans that match your users' needs.

No, ECG provides connectivity to an existing global MVNO, delivering the link for voice calling and a path for data.

You don't need to negotiate carrier agreements, build infrastructure, or handle the complexity of becoming a mobile network operator – ECG handles the eSIM supplier for business relationships, letting you focus on your VoIP service.

Fixed-mobile convergence (FMC) integrates desk phones, mobile devices, and VoIP systems into a unified service. Users have one business phone number that works across all devices. FMC caller ID displays your business number when making calls from smartphones, not users' personal mobile numbers.

This maintains professional identity and ensures callbacks reach your UC system, not personal devices, while providing seamless mobility without call forwarding or simultaneous ring.

Yes, you can provide custom network profiles displaying your company name on the phone screen and in line descriptions.

For example, if your company is called "Magic," users see "Magic" instead of Verizon, T-Mobile, or AT&T, reinforcing your brand identity on every call they make through your business eSIM service.

Yes, you can create your own competitive service based on your voice offerings with full mobile connectivity.

It's up to you to design the product – combine it with SIP trunking, business desk phones, contact center features, or WebRTC capabilities.

ECG provides the eSIM and fixed-mobile convergence foundation; you differentiate through your unique service packaging and vertical market focus.

Emergency calls always route through the radio network operator (the local cellular carrier) to guarantee callers the fastest possible access to emergency services.

This ensures FMC phone calls to 911 or 112 work reliably regardless of your VoIP platform's configuration, meeting regulatory requirements and providing proper location data to emergency responders.

The best business travel eSIM and most secure eSIM for business use depends on your requirements. ECG's solution uses encrypted SIP connections from phones to your VoIP platform, keeping business communications private.

Since calls route through your UC system, you maintain full control over call recording, compliance, and security policies – unlike consumer eSIM services, where the carrier controls everything.

For leading IoT eSIM providers or specialized vertical deployments, ECG can recommend configurations that meet specific security and operational requirements.