National Roaming allows SIM cards to use more operators in a country. This can be a big advantage to be certain of good coverage in a country. If your device is at a location with poor reception, it can switch to the best network. In case of a network outage, it switches to another network for continued service. Or if you use 2G hardware and your operator discontinues the 2G service, you can avoid problems. By having more networks available you can switch operator without any hassle.

What is so special about national roaming?

National Roaming works as if you're using cellular services abroad. You’re not on your home network but roam freely on other networks. It’s a way of saying your SIM card has no home network, but can use any. There are some regulations around national roaming and good reasons for it.

To deploy a mobile network, the Mobile Network Operator (MNO) needs frequency licences from the government. This allows the MNO to use certain frequency bands and prohibits anyone else from using it. 

These licences are up for auction and expensive, because of the limited capacity. This puts out a threat for a monopoly in the market. Because of its costs, only a few companies can afford the licences and this limits competition. Governments try to counter this in two ways. 

First, in smaller countries demand a nationwide roll-out. This prevents scenario in which operators create their own territories. For example, MNO A captures the market in the Northern part and MNO B on the South part of a county. Avoiding having to compete for customers. 

Second, it’s not allowed to share users on each other’s networks. With exceptions for governmental usage and emergency services.

These conditions prohibit national roaming, and that is why any national roaming SIM has to be a foreign SIM. 

How is National roaming offered?

Olivia Wireless offers SIMs that come with an International phone number. Not linked to a specific country, this allows for using many networks per country. Other operators might deploy SIMs from a small subsidiary mobile network they own. This doesn’t allow to roam in a less important small area, but it will in countries that matter to customers.

National Roaming offers you the best coverage in any country and can be very helpful. It is another way to assure quality for your IoT deployment.