Whether there is a fee depends on the type of service you are using. Please see the breakdown below:
📱 Landline SIM - Mobile Numbers
Port-in Fee: £0 (Completely Free)
Failed/Subsequent Ports: £0 (No charge)
Status: Mobile porting is always free of charge at ONSIM.
📞 Landline SIM - Landline Numbers
First Port-in: £0 (Free)
Subsequent Ports: £20 + VAT
Failed Ports: £20 + VAT
Note: We cover the cost of your very first landline port-in for this service.
☁️ Virtual Landline - Landline Numbers
Port-in Fee: £20 + VAT (per number)
Failed Ports: £20 + VAT
Status: All ports into the Virtual Landline service are chargeable.
| Service Type | Number Type | Port-in Fee |
| Landline SIM | Landline Number | Free (for the first port) see above |
| Landline SIM | Mobile Number | Free |
| Virtual Landline | Landline Number | £20 + VAT |
💡 Why did I get charged?
Fees are only applied to Landline SIM (after the first port) and Virtual Landline services. To avoid failed port fees on landline services, please ensure your address and name details match your current provider's records exactly.
📖 Step-by-Step Porting Guides
Ready to start your transfer? Select the guide for your service type below:
⚠️ Pro Tip: To avoid the £20 failed port fee, please ensure your account details (Name, Address, and PAC/Postcode) exactly match the details held by your current provider for the number.