How to Make and Receive Calls from any Country*

eSIM or Dual SIM? Information on SIM card choices for Travellers.
Calling Account Roaming Feature Explained Here.
*Roaming is available in the vast majority of countries with Mobile Network Coverage.

how does a calling account use global roaming? what type of phone do i need?


Direct Calling

With a Calling Account you do not need to have a Cell Phone or an internet connection to make calls!

If you are at home or abroad, you can use an ordinary landline phone connected via the local PSTN and dial a Country Access Number – this can be a Local Number or a Freephone Number. You will need to check with your Calling Account provider to see which countries have Local Access Numbers available.

Most people now use a Mobile Phone, or cellphone, and for this to operate in any country, and assuming Wi-Fi is not available for Internet Calling, you will need a Voice enabled SIM card – which may be provided by your own or another Mobile Network Provider. 

If you are out of your own country, the SIM card can be changed to another International SIM card provided by a different Mobile Network – this means a new Number or “id”for your cellphone.

Phones operating Dual SIM cards are particularly useful because the additional SIM can be with another Network i.e. not your Home Network, and comes with a second private or personal number. 

Internet VOIP Calls

For Internet Calling a second personal number can often be obtained from your Calling Account provider.

What is a SIM card?
What types of SIM card do i need when i am overseas?


SIM stands for Subscriber Identity Module, and it’s just a simple memory chip that holds identity information about cellphone users. 

All Mobile Phones need a SIM card – this is the way that Mobile Network operators like Vodafone etc allocate you a telephone number or “id”  – short for “identity” – so that calls can be routed and billed correctly to and from your mobile phone or cell phone.

Most SIM cards are Voice and Data – which means you can make and receive voice calls through the Mobile Network and access the Internet.  Data Only SIM cards means that the Operator’s Voice Network is not used, but the device or cell phone has Internet Access and sometimes can accept incoming SMS or text messages.

To use all the Calling Account features, you will need access to the Internet so either you need to use any available wi-fi for example – or an International Data SIM.

A phone with Dual SIM capability is a good choice to utilise the features available with the modern Calling Account. 

The image below shows the various types of SIMCard now available and how they have evolved in size from Mini to Micro to Nano and now eSIM. You need to check what type of SIM you have in your handset

SIMCard Types
Mini, Micro, Nano and eSIM

Wi-Fi a cheaper Option for phonecalls?
What are international SIM cards?

using mobile phone with laptop
using mobile phone with laptop

Newer and more expensive  Smartphones use eSIM, which is not a real SIM card, but rather an integrated chip.  

A SIM card is a chip that is physically installed into or removed from your phone configured with your carrier’s plan. An eSIM (embedded sim) is built-in to your phone and downloads your carrier’s plan indirectly.

This allows users to choose their Network Service Provider and can instantly be activated if you switch Networks.

International SIM Cards or Travel SIM Cards replace the SIM card you would use with your Home Network, and they enable international Roaming. 

This means that you can continue to use your cell phone to make direct calls from other countries, but with a different pricing to calls you would make at home.

Some Mobile Networks allow International roaming calls from one or several other countries without the need to replace your SIM card, but very often the cost of making and receiving these roaming calls is much higher than if you were calling from home.

With a Calling Account, and access to the Internet which may also be FREE from Wi-Fi in your hotel or other area you can use a cellphone or tablet or laptop to make and receive calls from abroad at the normal call rates and use all the Calling Account features available.



If you have a UK Network provider (Vodafone, O2, EE and Three are the main four), from 2022 Network Operators will not be allowed to block any handsets provided as part of the contract – more about this on our favourite Blog Site here.

Many customers have Mobile Phones that are “locked”. This simply means that your Network Provider controls your Internet access and how you make calls on your phone, and you cannot switch to another – potentially cheaper – provider: if you try to insert a SIM card which does not belong to your Mobile Network, it will not function.

So what can you do?

Basically you have two choices if your Network Operator cannot provide the Roaming service you want.

Firstly, you can see if the phone can be “unlocked”. This can be a difficult process, but it may be possible depending upon the contract you have.

Secondly, you can either purchase or hire another “unlocked” mobile phone which will accept any SIM card package. There are reasonably cheap options available and  a rental deal can be an economic solution  and save you a significant amount of money in the longer term, especially if you plan to use your Mobile phone extensively while you are abroad. 

We recommend that you check out the  International  SIMCard provider  we feature in our Video below. They provide worldwide solutions both for Individuals and Corporate customers resident in any Country.


We recommend the OneSimCard products: you can also rent mobile phones from OneSimCard if your phone is locked.

Please watch the Video and then click on “Start Saving”

OneSimCard - save up to 85% on your cell phone calls while abroad