When you buy a phone number that uses Voice over Internet Protocol (VoIP) to make calls, you’ll have to decide between fixed or non-fixed VoIP.

Put simply, fixed-VoIP is tied to a specific physical location. A non-fixed VoIP number is not tied to a place at all — it’s tied to a user. You may have also heard non-fixed VoIP numbers referred to by other common names like:

• Virtual phone numbers.
• Internet phone numbers.
• Cloud phone numbers.

Unlike traditional phone numbers, which are linked to a landline or a specific geographic area, non-fixed VoIP numbers operate over the internet and can be used to make and receive calls from anywhere in the world with an internet connection.

To get a fixed VoIP number, you’ll have to give a physical address for emergency services geolocation and meet additional regulatory requirements.  This makes fixed VoIP numbers a better option if you operate from a single location and must stick to local regulations or require access to emergency services.

To get a non-fixed VoIP number, you just need an email address, the internet, a few bucks, and a tiny bit of ambition. You’ll be able to start making calls almost immediately.

5 Scenarios to use non-fixed VoIP

I fall into the camp of people who think you should use non-fixed VoIP unless you absolutely need to have a fixed VoIP number for compliance. It’s cheap, it’s easy, it’s flexible, and in the scenarios I am about to cover, it’s just the better all around option for businesses and their customers.

There are a ton of great business VoIP phone services to replace or upgrade an aging system, as well as free VoIP services for individuals. In both cases, you will have the option to select a fixed or non-fixed VoIP number. If you are new to this tech, check out our guide to VoIP so you can make an informed buying decision.

1. Local presence in target markets

Most people don’t pick up calls from numbers they don’t know, but if the area code is the same or close by, it increases the chances of someone picking up.

With a non-fixed VoIP number, you can create a local presence in your target market by purchasing numbers with area codes in your target market. You don’t have to have a physical office in the area, but you can make it seem that way to customers and clients.

You can probably see how this could be a scammy tactic, not really that different from spoofing your caller ID number. That’s true, and scammers certainly use local area codes in order to get callers to pick up.

But plenty of legitimate businesses use this tactic for perfectly good reasons. Let’s say a doctor’s office has outsourced after-hours communication to a virtual contact center. They want to set those customer service reps up with a local number so that patients pick up the call, don’t block the text message, or listen to the voicemail.

When it comes to cold calling, using “local” non-fixed VoIP numbers is a way to increase contact rate. Potential customers are much more likely to pick up the phone if they see a call coming from a local number for all the same reasons we’ve discussed.

2. Remote and hybrid teams

If you have remote work or teams distributed across different locations, non-fixed VoIP numbers are likely your best choice. Maybe you need a single fixed VoIP number for the office (or offices), but assigning non-fixed VoIP numbers to employees gives them a consistent business contact number, regardless of where they are located.

This kind of flexibility can make a real difference. It ensures team members stay accessible to both clients and colleagues. With a lightweight VoIP solution like OpenPhone, employees can add a separate business line to their mobile phone. That means your team can maintain professional communications without disclosing their personal contact information.

Also, your non-fixed VoIP numbers can easily come with you if your business ever needs to move to a new location. Not having to deal with regulations and location verification can allow for a smoother transfer of your operation to a new site without disrupting your communication system.

3. International calling

If your team is based in the U.S. and makes a lot of calls outside North America, going with non-fixed VoIP numbers could save you a bundle.

How much? You can save something like 80-90 percent on the cost of international calling by using VoIP instead of landline phones.

Getting non-fixed VoIP numbers in the countries where you regularly do business is relatively easy. This lets you avoid the hefty costs associated with international calling minutes.

Because you’re not concerned about running up a huge phone bill, your team can make more frequent outgoing calls to different countries. That kind of increased contact can help you progress faster on big goals like market penetration, improved service for international clients and more sales leads.

For incoming lines like customer support, you can establish multiple local or toll-free numbers in each country where you work. That makes it easier for customers to reach out for support without paying long-distance charges.

4. Marketing campaign tracking

For marketing campaigns, the ability to track your performance is critical to success. For call centers, non-fixed VoIP numbers make tracking possible by letting you monitor your campaign’s progress precisely.

You can assign different non-fixed VoIP numbers to various campaigns and use the numbers to monitor their effectiveness.

By analyzing call volume and origin for each number, you can get insights into which campaigns are performing well and which calling areas are most responsive.

This information is critical for measuring which interactions truly contributed to revenue, and ensuring your efforts are targeted and efficient — key ingredients for maximizing the ROI of your campaigns.

5. IT failover solutions

Non-fixed VoIP is ideal as a failover option because of its flexibility and ease of deployment. In the event of an outage, teams can access non-fixed VoIP numbers from any internet-connected device, whether they’re in the office, at home, or on the road.

This flexibility allows for uninterrupted communication and immediate failover, which is especially beneficial for managing business continuity with remote workers or those needing fast, adaptable solutions.

Setting up non-fixed numbers is quick and typically requires minimal infrastructure, so businesses can activate them on short notice without the need for physical equipment. This makes non-fixed VoIP a good choice for smaller businesses or those with fluctuating communication needs.

One thing I want to mention is that a fixed VoIP line may be the better contingency option for some businesses. Fixed VoIP is tied to a specific address, which enhances reliability, simplifies call authentication, and ensures accurate location data for emergency services. For businesses requiring a highly secure, location-specific failover system, fixed VoIP is the better failover strategy.

Can you trace a non-fixed VoIP number?

The short answer is — yes, but you might need the help of law enforcement.

Whereas fixed VoIP numbers are easily traceable because they’re tied to registered physical addresses, tracing a call from a VoIP number that’s not fixed is going to be close to impossible for the average person, especially if the caller has taken steps to mask their identity.

VoIP providers maintain logs and records of incoming and outgoing calls, which could include IP addresses, call times, and durations. But accessing this information is complicated because privacy laws in many places protect this kind of data. There are specific limits concerning who can access it and under what circumstances.

Unless you work in law enforcement, you’d need to overcome some significant legal hurdles, like demonstrating a legitimate need for the information that outweighs data privacy expectations. Still, legal and procedural requirements can make it a slow process.

Authorities need a court order or warrant before forcing a VoIP service provider to release call records or logs. That process involves showing probable cause or a reasonable suspicion relevant to an ongoing investigation or criminal activity.

And even with legal authorization, the technical process of tracing a call through various servers and potentially across borders can be complex and time-consuming. Non-fixed VoIP calls can easily travel across international borders, involving service providers and data centers in different countries.

Of course, each country has different privacy laws and regulations about data access. This makes international cooperation and legal compliance another potential hurdle for any efforts to trace non-fixed VoIP calls.

Should you choose non-fixed VoIP numbers?

Yes, unless you have a compelling reason not to, such as meeting emergency call compliance. Beyond the regulatory reasons, if you truly believe that the greater degree of trust in a fixed VoIP number will benefit your business, do it.

But for the average user, a non-fixed VoIP number is cheaper, more flexible, and easier to set up. In the scenarios I covered in this post, non-fixed VoIP is actually better than a fixed line.

If you need to scale your operations, penetrate new markets, level up your customer service, or make your operations more resilient, choosing non-fixed numbers is usually the way to go.

Learn more about securing your VoIP phone system for the future and what you should expect to pay for VoIP.