ONSIM LTD – Regulatory & Compliance Summary

Last updated: 25th November 2025
Company name: ONSIM LTD
Company number: 08429703
Registered in: England & Wales
Registered office: 86-90 Paul Street, London, EC2A 4NE
VAT number: GB163518900

1. Telecoms Regulatory Status

ONSIM LTD provides publicly available telephone services (PATS) in the UK.
Our services operate over licensed UK mobile network infrastructure and allow customers to make and receive calls using both mobile and geographic (landline) numbers.

Under the UK’s General Authorisation Regime, PATS providers do not require an individual licence from Ofcom.
ONSIM operates legally and compliantly under the Ofcom General Conditions of Entitlement, which apply to all UK communications providers.

ONSIM does not install physical telecoms infrastructure (e.g., masts, ducts, poles).
Therefore, we are not required to appear on Ofcom’s Register of Persons with Powers under the Electronic Communications Code.
This register applies only to operators deploying physical networks that require statutory land-access rights.

2. Ofcom General Conditions Compliance

ONSIM complies with the relevant Ofcom General Conditions, including but not limited to:

GC A1 – Fair and Transparent Contract Information

Clear terms, pricing, cancellation rights, and treatment of vulnerable users.

GC C1 – Complaints Handling

ONSIM maintains a formal complaints process and is registered with an independent Alternative Dispute Resolution (ADR) scheme Ombudsman Services.

GC C7 – Number Portability

Customers can port numbers in and out of ONSIM.
We support geographic (01/02) and mobile (07) porting in accordance with Ofcom rules.

GC B3 – Emergency Services Access (999/112)

Emergency calls are supported.
Both the customer’s mobile (location) and registered landline calling information are delivered to the Public Safety Answering Point (PSAP) for correct routing and caller identification.

GC A3 – Network Resilience & Service Reliability

ONSIM services operate using established UK mobile network infrastructure to ensure continuity, reliability, and high call quality.

3. Numbering & Calling Line Identification (CLI)

  • ONSIM assigns and manages UK telephone numbers in accordance with Ofcom’s numbering plan.
  • CLI presentation follows Ofcom guidance.
  • For customers using a geographic “landline” on a mobile SIM, the landline number is correctly presented on outbound calls and is fully return dialable.

4. Data Protection & Security

ONSIM complies with:

  • UK GDPR
  • Data Protection Act 2018
  • Telecommunications (Security) Act 2021, where applicable

We maintain strict controls around the processing of call data records, customer information, and location data where required for emergency services.

5. Complaints & Dispute Resolution

ONSIM provides a clear internal complaints process.
If a complaint is unresolved after 8 weeks, customers may escalate free of charge to:

Ombudsman Services: Communications
(ONSIM LTD is registered with an ADR scheme as required by Ofcom.)

6. Summary of Regulatory Position

✔ Fully registered UK company
✔ PATS provider operating under Ofcom’s General Conditions
✔ Emergency services (999/112) supported — mobile and landline data delivered to PSAP
✔ Number porting compliant (inbound and outbound)
✔ ADR scheme membership (Ombudsman Services)
✔ Not required to be on the Electronic Communications Code register - (as we do not deploy physical telecoms infrastructure)

If you have any questions about our compliance or legitimacy, please feel free to reach out to our team support@onsim.uk or call us on +44 333 880 4008.