eSIMs are small, programmable chips embedded into a device’s motherboard. ESIMs are very convenient to update, especially if your device is in a hard to reach place!

The key thing that makes eSIMs so powerful is that they do not come with a single operator package pre-programmed onto them. Instead, eSIMs start off blank and have packages installed onto them as and when they’re needed. These packages can be uninstalled and replaced at any time, meaning you could install a Vodafone SIM package onto an eSIM and then later decide to uninstall that package and replace it with another operator like EE.  Many devices allow you to have multiple eSIMs loaded at the same time.

Most of the major UK mobile networks are now providing eSIMs, mainly with monthly contract plans rather than PAYG, and most new smartphones are being designed to support them. It's becoming increasingly common for cellular routers to natively support eSIMs, including the RUT241, RUT9** series, RUTM** series, and RUTX series to name a few from the Teltonika range here at Solwise.

What are the benefits?

Through eSIM, you can purchase SIM packages from multiple networks and use whichever one happens to be strongest in the area you’re currently located. This is particularly useful if you travel to different places, where the performance of a single mobile network can fluctuate. eSIMs can also be used for travelling outside of the UK, with local SIM packages downloaded to an eSIM rather than relying on expensive data roaming charges from a UK SIM network.

eSIMs also pose a great advantage when it comes to sailing internationally while using a mobile router. Instead of physically swapping out one SIM card for a new local one when moving from one country to another, a new local SIM package can be programmed onto the eSIM instead. This means you don’t have to worry about placing the router somewhere easy to access and potentially hindering its performance (since it works best when high up and out of the way).

What Solwise equipment can eSIMs be used with?

We have a growing number of eSIM supporting Teltonika routers.  The key advantage of these routers is that they come with the eSIM pre-embedded onto the motherboard so you don't need to do anything yourself to set it up. Instead, you just need to access the router's web interface and enter your eSIM package's activation code (note that the router will need a separate internet source for this to work, such as another router going into its WAN port). It is worth noting that all the eSIM routers also offer a standard SIM slot, or two, for backup.

Among the several eSIM-supporting Teltonika routers is the RUT241-eSIM, which is a reliable 4G router suitable for various applications. There is also the RUTM30, a cost-effective 5G router, and the OTD500, a 5G router designed for outdoor installation (eSIM can be particularly beneficial with this router because it allows the SIM to be changed without needing to physically access the router, which may be mounted up out of the way). Additionally, the dual-modem RUTM52 is another 5G router that supports eSIM. This can be especially powerful because its dual-modem design allows you to use the eSIM alongside a physical SIM card.  

See the full range of eSIM routers, including those mentioned above and more, on our Mobile Routers page - there is an eSIM filter tag to narrow them down.

Updated: 27.01.2026