Non-Fixed VoIP: Everything You Need to Know

Over the past decade, voice over Internet Protocol (VoIP) has risen steadily in popularity as a powerful and inexpensive alternative to traditional phone lines. Between 2010 and 2018, the number of VoIP business lines in the U.S. rose from 6.2 million to over 40 million. One of the most frequently asked questions regarding VoIP is the difference between fixed and non-fixed VoIP phone numbers so I have put together a comprehensive guide to help you decide whether fixed or non-fixed VoIP is right for your organisation.

What Do Fixed and Non-Fixed VoIP Numbers Have in Common?

Before we dive into the differences between the two types of VoIP numbers, let’s take a look at what they have in common. Both fixed and non-fixed VoIP numbers:

  • Rely on the internet to make and receive calls
  • Use the same VoIP devices
  • Can be configured to support text messaging capabilities
  • Offer the same range of VoIP-related benefits

Both fixed and non-fixed VoIP numbers tend to lower the cost of communication when compared to traditional phone lines. In fact, the average business saves between 30% and 50% of communication costs by switching to VoIP. However, depending on whether you’re calling with a fixed or non-fixed VoIP number, customers may be more likely to be suspicious of your calls. Moreover, the speed at which you reach emergency services may be impacted.

So, what are the major differences between fixed and non-fixed VoIP numbers? And why would a business choose one over the other?

What Is a Fixed VoIP Number?

A fixed VoIP number is linked to a physical address, such as an individual’s home or work address. Fixed VoIP numbers are assigned by a VoIP service provider with a broadband network linked to the common public switched telephone network (PSTN). While fixed VoIP numbers are internet-based, they are similar to traditional phone lines in that they require a physical address to be provided in exchange for service. Because fixed VoIP numbers require an address, and therefore an owner, they’re regarded as more credible than non-fixed VoIP numbers. This affects whether your customers will feel inclined to pick up calls from you.

Moreover, scammers tend to prefer non-fixed VoIP numbers because the absence of an address requirement makes it easier to mask their identity. VoIP service providers also tend to charge for fixed VoIP numbers rather than offer free services with quick signup. One key advantage of fixed VoIP numbers is that, unlike non-fixed VoIP numbers, they send the exact location of a dialler to public safety answering points (PSAPs), allowing the call to be traced in an emergency.

What Is a Non-Fixed VoIP Number?

A non-fixed VoIP number, otherwise known as a virtual phone number, isn’t linked to a physical address. Non-fixed VoIP numbers have the same calling capabilities as fixed VoIP numbers, and can likewise be used for residential or business purposes. While non-fixed VoIP numbers aren’t tethered to a geographical location, accounts can be created to serve any desired address. This allows businesses to contact customers all over the world. In addition to establishing a local presence, non-fixed VoIP numbers can bring together remote teams and unify global communications.

Non-fixed VoIP numbers are easier to put in service than fixed VoIP numbers. Platforms such as Google Voice and Skype offer non-VoIP numbers in return for as little information as a name, email address, and payment information whenever relevant, although these services are usually low-cost or free. Calls made through non-VoIP numbers can’t be traced easily by emergency services. When implementing a non-fixed VoIP solution for your business, reminding your employees of this limitation can make a difference during emergencies.

Why Do Scammers Prefer Non-Fixed VoIP?

Nearly half of illegal calls rely on VoIP technology. That’s because non-fixed VoIP numbers are generated easily—sometimes requiring nothing more than email confirmation—and don’t need to be linked to an account holder’s address. Caller ID information can be spoofed, offering anonymity or aiding impersonation. A non-fixed VoIP number is a perfect tool for chain-dialling with a basic script while masking the identity of the caller and costing the spammer little to nothing.

Prolific spam calls have given rise to the development of countermeasures. APIs now exist that identify what type of number an individual is calling from based on multiple data points that are combined to form a reputation score. Numbers that are likely to represent a spam call are flagged and blocked.

Pros and Cons of Fixed VoIP


  • Your business appears authentic. Fixed VoIP numbers are less associated with spam calls, lending credibility to calls made on behalf of your business
  • You gain access to more advanced features. Fixed VoIP lines generally offer a more advanced set of calling and call routing features
  • Your location is retrievable during emergencies. Your employees don’t need to worry about switching to their cell phones when dialling


  • You will require more setup time. VoIP service providers generally require more information from users to set up a fixed VoIP number
  • You may pay more. Advanced feature sets typically come at a cost. Long-distance and international calls may also be more expensive

Pros and Cons of Non-Fixed VoIs

  • Pros:
  • You extend your business’s reach. Non-fixed numbers aren’t bound to any geographical location, letting you reach customers wherever they may be
  • You spend less time on setup. Platforms that offer non-fixed VoIP numbers usually require little more than a valid email address
  • You typically pay less (or nothing at all). Basic calling capabilities are often free, regardless of whether you’re making a local, long-distance, or international call


  • You may appear unprofessional. Spammers tend to rely on non-fixed VoIP numbers. This can make calls made on behalf of your business seem less trustworthy
  • Your location isn’t easily traceable. Emergency personnel won’t be able to track your location when calling with a non-fixed VoIP number

Why Do Businesses Choose Non-Fixed VoIP?

There are many reasons why a business will opt for a non-fixed VoIP number. Here are a few of the most common reasons why a business will use this option. They want to establish a local presence.

They Want to Collaborate Remotely

Regardless of where your employees are located, non-fixed VoIP numbers can bring your remote teams together and keep them connected. Non-fixed VoIP is easy to set up, easy to use and accommodates a wide range of hardware options. Depending on the VoIP service provider you choose, you can gain access to the advanced features typically associated with fixed VoIP, including virtual faxing, audio and video conferencing, business SMS and MMS, and more.

They’re on a Budget

One of the biggest advantages of non-fixed VoIP is its cost-effectiveness. Because non-fixed VoIP numbers are easy to set up, accommodate flexible hardware options, and are typically cloud-based, startup costs and phone plans are often very affordable. Fixed VoIP systems, on the other hand, tend to charge for more flexible features and add-on business tools.

Why Do Businesses Choose Fixed VoIP?

Fixed VoIP numbers offer several benefits over non-fixed options. The most common reasons why a business chooses this option include:

  • They want to appear authentic
  • Fixed VoIP requires an address. If a business is well-established in a local area, opting for a fixed VoIP system adds to their authenticity when serving customers in their community

While non-fixed VoIP numbers were once associated with scammers, systems have been developed and routinely implemented to counteract fraudulent activity, improving the reputation of non-fixed VoIP. For example, APIs exist that allow users to determine whether a phone call is likely to be a spam call based on a comprehensive list of contributing factors.

One way to make sure calls made from your non-fixed VoIP number don’t get caught in spam filters is to register that number through free online business directories such as Google My Business, Yelp, and Bing Places. That way, your business information is displayed when customers type your phone number into one of these directories. As a bonus, many phones will automatically match phone numbers to business information found online, improving your pick-up rate.

Just like non-fixed VoIP, fixed VoIP can be used for personal or business use. When it comes to replacing a traditional phone system for your business, fixed VoIP provides a high-quality, reliable communications system that incorporates a variety of business productivity tools.

While non-fixed VoIP has been associated with platforms such as Google Voice and Skype—which offer quick signup and free or low-cost basic calling capabilities—many VoIP service providers now target business collaboration.

Depending on the VoIP service provider you choose, non-fixed VoIP systems now offer sophisticated features such as audio and video conferencing, virtual faxing, auto-attendant, business SMS and MMS, and more.

Fixed or Non-Fixed: Which One Is Right for My Business?

Every business has different needs. These needs may also change over time. While a non-fixed VoIP system may be better suited for a growing business over the short term, a fixed VoIP system may offer unique benefits when well-established within a local community.

A fixed VoIP number is well-suited for stable businesses that are known within the local area. For example, established enterprises with headquarters in one location may prefer fixed VoIP to capitalise on its local presence. Fixed VoIP also offers call tracing during emergencies.

A non-fixed VoIP number is perfect for businesses that are still growing or new to the scene. Businesses with employees that work remotely or travel frequently will pay less in long-distance or international calling costs and enjoy flexible hardware options. Non-fixed VoIP is also easier and faster to set up than fixed VoIP.