Comparison guide
Virtual Landline vs VoIP: Which Is Better for UK Small Businesses?
Many UK businesses searching for a virtual landline end up looking at VoIP phone systems too. The problem is that they are not the same thing, and the wrong choice can leave you paying for features you do not need or forcing your team into a clunky calling setup.
What is a virtual landline?
A virtual landline is a UK business number that is not tied to a physical desk phone or copper line. Calls might be forwarded to a mobile, delivered through a VoIP app or handled in a more mobile-native way via SIM/eSIM.
In practice, many businesses use the term when they really mean “I want a proper business number that rings on my mobile”.
What is VoIP?
VoIP stands for Voice over Internet Protocol. Instead of calls being handled as normal phone calls, they are carried over the internet through apps, softphones or IP desk phones.
VoIP can be powerful, but it usually brings more complexity, more setup work and more dependency on data, Wi-Fi and app behaviour.
The short answer
If you want a business number on your mobile with the least friction, a virtual landline is usually the better starting point. If you need extensions, complex call flows, lots of users and integrations, VoIP may be the better fit.
| Feature | Virtual Landline | VoIP |
|---|---|---|
| Best for | Sole traders, small businesses, mobile teams | Desk-based teams, multi-user phone systems, heavier call routing needs |
| Setup effort | Low | Medium to high |
| Uses your normal mobile dialler | Sometimes, depending on delivery method | Usually no |
| Depends on app or data connection | Not always | Usually yes |
| Can be very low cost | Yes | Less often |
| Advanced team features | Limited on simpler plans | Usually strong |
Choose a virtual landline if…
- You want a professional UK business number quickly.
- You mainly need inbound calls to ring on your mobile.
- You want to avoid app rollout and VoIP complexity.
- You care about keeping costs down.
Choose VoIP if…
- You need multiple users, extensions and advanced routing.
- You are comfortable running calling through apps or desk phones.
- You need integrations with CRM or helpdesk tools.
- You are willing to trade simplicity for features.
Choose Landline SIM if…
- You want a mobile-first setup with less friction than VoIP.
- You want outbound calls to show your landline number.
- You want business calling to feel like a normal mobile call.
- You want a cleaner upgrade path than basic forwarding.
ONSIM’s position, in plain English
If you just want a virtual landline that rings on your existing mobile, ONSIM Virtual Landline is the simple answer.
If you want something closer to a proper mobile business phone system, without relying on a VoIP app, ONSIM Landline SIM is the better fit.
FAQs
Is a virtual landline the same as VoIP? v
No. A virtual landline is a broad category for a UK business number that is not tied to a physical phone line. Some virtual landline services use VoIP, but others use simple call forwarding or SIM-native delivery.
Which is better for a mobile-first business? v
If your business runs primarily on mobile, a simple virtual landline or SIM-native setup is often a better fit than a VoIP app, because it usually involves less friction and fewer reliability issues on the move.
Is VoIP cheaper than a virtual landline? v
Not always. Basic virtual landline services can be cheaper than VoIP, especially if you only need a business number and inbound calls. VoIP can become more expensive once you add users, numbers, features and support.
Can I make outbound calls showing my landline number? v
With many virtual landline products, no. With VoIP, often yes. With ONSIM Landline SIM, yes — without using a VoIP app.