| 5 min read

What are Inbound Numbers?

Inbound Voice is a cloud-based telephony service for both geographic and non-geographic numbers that provides online access to a full range of call routing, monitoring and management tools; supporting your organisation to provide high quality customer service.

5 min read


An introduction to inbound voice and inbound numbers (UK)

Inbound numbers are important for organisations as many people still prefer calling a business to receive support, make a purchase, or to get information. So, using a telephony option such as inbound numbers to provide the best service for your customers is key, and there are a range of numbers that can support your business.

1. Types of inbound numbers

Business phone numbers are essential to provide a presence and allow customers to communicate with your business. There are a range of numbers which a business can use to enable this communication, as highlighted below.

What are Non-geographic numbers, or NGN numbers?

Non-geographic numbers, or NGN numbers, are numbers that are not linked to any specific location, which means calls can be routed to virtually any destination, and this routing can be adjusted depending on a range of factors, like the time of the call.

There are 3 types of NGN numbers:

Cost Benefits
Shared cost

The cost of the call is split between you and the caller, where you may receive a share of the revenue. There are a range of tariffs available which vary by country, and by asking the customers to pay a share of the cost, you indicate the value of the service you’re providing and reduces the number of junk calls you receive.

Resilience and Flexibility

Calls are free of charge for the caller, as the service provider pays for the full cost of the call, which makes it ideal for customer service applications or advertising campaigns. These can be used nationally, within your own country, or be extended into other countries.

Easy to Manage
Premium Number

The caller pays the entire cost of the call and you receive a share of the revenue, where you can set the rate the caller pays by selecting from a range of pre-defined tariffs.

What are Geographic numbers?

Geographic numbers are local numbers (effectively the opposite of geographic numbers, or NGN numbers) that represent a geographical location, which allows customers to identify your organisation with a specific location. This can be available in a country where you usually operate nationally, or in your sites abroad (if you do not have a cross-border site you can give your company a virtual presence overseas instead).

What are Universal International Freephone Numbers (UIFN) numbers?

A Universal International Freephone Numbers (UIFN) is a global toll-free number that can be dialled from over 60 countries around the world. These calls may be routed internationally to the destination of the customer’s choice.

What are International Toll-Free Number (ITFS) numbers?

An International Toll-Free Number (ITFS) is a domestic Freephone number that varies by country, where the calls made to an ITFS are toll free for the caller.

To find out more about the inbound numbers we offer at Colt and how they can benefit your organisation, please click here.

2. Common inbound numbers explained

0808 Numbers are Non-geographic Freephone numbers in the UK and most European countries. These are commonly used by businesses as it allows customers to call them for free, which encourages them to contact them (e.g. sales lines). They are free for the caller as the receiver pays for the full charge of the call.
0330 Numbers are Non-geographic shared cost numbers in the UK. They are used by businesses as it gives them flexibility to have a number which is cheap to call, without being linked to one specific area. They are charged at the national rate for the caller.
0808 Numbers are Non-geographic UK Freephone numbers which function similarly to 0800 numbers. They are used by businesses as it gives them flexibility to have a number which is cheap to call, without being linked to one specific area. They are free in the UK, as the receiver pays for the cost of the call.
0844 Numbers are non-Geographic service numbers. Used for contacting organisations and the service charge involved helps pay for the service being provided (e.g. ticketing services). These are charged at special rates which tend to be higher than normal calling costs.
0906 Numbers are premium rate UK numbers that are more expensive than traditional numbers. These numbers are used by companies looking to monetise a service they offer to their customers (e.g. TV voting or competitions). These numbers are the most expensive numbers to call in the UK and can cost over £2 per minute.
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3. Our inbound numbers solution

At Colt, we have a range of inbound numbers to support your organisation, including all of the numbers mentioned in this guide:

  • Non-geographic numbers / NGN numbers
  • Geographic numbers
  • UIFN numbers
  • ITFS numbers
  • 0800 numbers
  • 0330 numbers
  • 0808 numbers
  • and much more

You can be sure that we can solve all your inbound voice needs. With us, you benefit from a global network in 28 countries, with third-party support in 142 countries.

All of this is available through us as a single supplier which will help you to consolidate your inbound voice services, reduce your costs, and give you a single point of contact for all your needs.

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Business Phone Numbers

Inbound Business Phone Numbers

Deciding what type of business phone number your organisation needs can be a tricky decision. There are plenty of different options that serve a variety of purposes, so it’s important that you find the right one best suited for your organisation.


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