ONSIM is the worlds most advanced mobile network, trusted by 7,500+ businesses in 39 countries.
Seamless network-level call & sms compliance recording that can't be bypassed. No apps or diverts!
Get a UK virtual landline number on your mobile from £5/mo — no app, no VoIP, no engineer visit. Local 01/02 and national 03 numbers available.
We're the first network in the world to offer a comprehensive API, offering unprecedented control of your mobiles.
Want to see current spend? Attempted calls? Or perhaps limit a user to only roam to or call certain countries? We've got you covered.
Native service in UK, NAM, EU with no roaming charges or limits. Traditional roaming in 195+ other countries.
Use AI for transcription, summarisation, coaching, compliance, sentiment analysis and more on native mobile calls.
Customers
FAQs
With all revolutionary technology there will always be lots of questions. The section below covers the most frequently asked, but please contact us if there is anything else you would like to know.
Mobile networks don't innovate. They've offered the exact same service since the 70's and whilst the phones we use have changed dramatically, the networks they rely on have not kept up. We're on a mission to disrupt the mobile industry and improve it for all.
Yes, all our unique features only work when you use our SIM's & network. You can port your existing mobile and landline numbers as you would to any other telecoms provider.
In the UK our network covers more than 99% of the UK population and 90% of the landmass and it's powered by the UK's leading network, winner of the overall performance category for RootMetrics' tests 9 years running. We also have WiFi Calling for low coverage areas. When our users travel to other countries we will sometimes change the network to give access to local services and remove roaming restrictions/charges.
Yes - you can port (or transfer) your existing landline or mobile number to use on the ONSIM service just like any other mobile network or telecom service provider.
It's your choice. Unlike other mobile networks ONSIM customers can display either a landline (01,02,03,08) or a mobile (07) number to the person they are calling. This is especially useful for hiding your personal mobile for work.
No - our service is SIM based it doesn't even have to be a 'smart' phone. This makes it more reliable and the call quality is far better than using a VoIP App.
The ONSIM blog is our narrative on the mobile industry, mobile tech and points of interest for our wide array of customers. We hope you find it useful and informative.
Two ways to record business calls on a mobile in the UK, an app on the device or at the network level via a mobile operator, with the honest trade-offs of each and what to look for when comparing providers.
A practical UK guide to call recording law. What private individuals can do, what businesses have to do, and the extra rules for FCA-regulated firms and businesses taking card payments.
Virtual landline or Landline SIM? Both give you a UK 01/02 number without a fixed line, but they work very differently. Here is how to choose.
The official story is modernisation. The fuller picture: £6 billion in copper, rising exchange costs, and a commercial case BT rarely mentions.