IoT SIM card providing multi-network connectivity across all four UK mobile networks for reliable business IoT deployments

Welcome to KeySIM

The UKs IoT SIM Card Specialist

Start Your IoT Project Explore IoT Features
83.9M+

MB transited in 2025–26

500+

UK Organisations

4

UK Networks Supported

400+

Global Networks

As seen in
Mobile News Broadcast Tech
Powering Channel 4's Hunted

KeySIM provides multi-network IoT SIM cards for UK organisations that require reliable, controllable connectivity.

Founded to address the limitations of traditional single-network solutions, KeySIM gives businesses the ability to connect devices across multiple mobile networks without restriction.

Today, KeySIM supports over 500 organisations across the UK, delivering connectivity for retail, healthcare, infrastructure and critical services.

Explore Our IoT SIM Connectivity Options

Not every IoT deployment is the same. Find the right connectivity technology for your devices.

Multi-Network IoT SIMs

Standard 4G/5G IoT connectivity that auto-switches between EE, Vodafone, O2 and Three for the strongest signal anywhere in the UK.

View IoT SIM cards →

M2M SIM Cards

Reliable device connectivity for payment terminals, CCTV, fleet and remote infrastructure.

View M2M SIM cards →

NB-IoT SIM

Low power, long-life connectivity for static sensors, meters and devices that send small amounts of data.

View NB-IoT SIM cards →

CAT-M SIM

Mobile IoT connectivity for asset tracking, telematics and devices that move or communicate frequently.

View CAT-M SIM cards →

Fixed IP SIM

Secure remote access to routers, CCTV and field equipment via private or static IP addressing.

View Fixed IP SIM cards →

Multi Network SIM

Unsteered access to all 4 UK networks on a single SIM, with remote network steering, UK breakout and stable fixed IP.

View Multi Network SIM →

Multi-Network Connectivity

Access to all four UK networks on a single SIM

There is no default network steering. Devices connect to the strongest available network in real time, improving uptime across varied locations.

EE
Vodafone
O2
Three
+ 400 global networks

Manage every SIM from one dashboard via the KeyOnline portal →

Not sure which SIM is right for your deployment?

Our team can advise on the right technology, pricing and setup — no obligation.

Contact the team Request a trial SIM
Trusted in Critical Environments

Connectivity Where Failure Is Not Acceptable

York Rescue Boat uses KeySIM to maintain connectivity during live rescue operations. In environments where connectivity failure is not acceptable, devices must remain online regardless of network conditions. KeySIM enables this by allowing devices to access the strongest available signal at any given time.

KeySIM

York Rescue Boat × KeySIM

How multi-network IoT SIM keeps crews connected on the water

Read the full case study →

What Our Clients Say

Trusted by UK Organisations
Across Every Sector

View all case studies →

Reliable connectivity across our store estate is essential. With locations spread widely across the UK, having access to multiple mobile networks on a single SIM provides the resilience we need to keep our systems operational.

SC

Shaun Chrimes

Head of IT & Information Security

Retail
Read case study

KeySIM has provided a reliable and flexible connectivity solution supporting teams where Ethernet networks were temporarily unavailable.

SS

Steve Senter

Technical Infrastructure Manager

Healthcare
Read case study

Having venues in a variety of locations means connectivity isn't always consistent on a single network. KeySIM's multi-network SIM gives us the flexibility to keep our systems connected where it matters.

CM

Chris Mountjoy

Director of IT

Hospitality
Read case study

KeySIM in the Press

KeySIM strikes remote SIM deal with Wired Broadcast

Mobile News | March 2024

Read the full article →

KeySIM featured in Broadcast Tech for powering Channel 4's Hunted

Broadcast Tech | October 2025

Read the full article →

York Rescue Boat upgrades emergency communications with IoT SIM connectivity

York Rescue Boat Case Study

Read the case study →

Network Growth

A 64× increase
in five years

KeySIM network usage has grown consistently as adoption across the UK has accelerated — from 1.3M MB in 2020–21 to 83.9M MB in 2025–26.

KeySIM operates its own UK network infrastructure as a RIPE NCC member (AS207652), providing managed IoT connectivity across the UK and Europe.

2020–21
1.3M
2021–22
10.2M
2022–23
22.0M
2023–24
24.2M
2024–25
40.7M
2025–26
83.9M

MB transferred

About KeySIM

Built by specialists with decades of connectivity experience

GR

Graham Robinson

Managing Director

CIMA-qualified accountant. Previously managed deployment of 30,000+ IoT SIMs.

JA

James Adam

Chief Technical Officer

30+ years' experience building connectivity software in the security industry.

MI

Marek Isalski

Infrastructure Director

35+ years' experience across ISP and infrastructure environments.

Credentials & Partners

Infrastructure you can trust

RIPE NCC Member (AS207652)

Own UK network infrastructure — not a reseller

RIPE NCC Member

Hardware Partner — Solwise

Compatible with a wide range of industrial IoT routers

Visit →

IoT SIM — Frequently Asked Questions

A multi-network IoT SIM card can connect to multiple mobile networks — EE, Vodafone, O2, and Three in the UK — automatically, with no network steering. Devices connect to the strongest available signal in real time.

Yes — KeySIM offers fully flexible Pay As You Go (PAYG) IoT SIM cards with no minimum contract requirements. You only pay for the data you use, with transparent pricing and no hidden fees. See our PAYG pricing here.

A Private Fixed IP address is a static, dedicated IP address assigned to your IoT SIM card that never changes. This allows secure remote access through VPN connections without exposing devices to the public internet. Learn more about Fixed IP SIM.

KeySIM supports EE (2G/4G/5G/NB-IoT/CAT-M), Vodafone (2G/4G/5G/NB-IoT/CAT-M), O2 (4G/5G), and Three (4G/5G). Our multi-network SIMs can also roam on 400+ networks globally. View the full global roaming list.

KeySIM is trusted by over 500 UK organisations across sectors including retail, healthcare, hospitality, construction, and emergency services. Read our IoT SIM case studies.

KeySIM offers several IoT SIM types: M2M SIM cards for payment terminals, CCTV and fleet; NB-IoT SIM for low power, long-life static devices; CAT-M SIM for mobile devices needing lower latency; Fixed IP SIM for secure remote access via private IP addressing.
View all FAQs →

Ready to Get Started with our IoT SIM?

Join over 500 UK organisations using KeySIM for reliable multi-network IoT connectivity. Flexible PAYG pricing with no minimum contracts.

Contact Our Team Request a Trial SIM View FAQs