Communication is central to every successful business. You need a reliable way of reaching co-workers, networking associates, and customers. Until recently, traditional landline phones have met this need.
But the times are changing. Modern businesses look to the latest innovations to deliver flexible and reliable communication. That’s where trunk lines come in handy. With this technology, you can say goodbye to bulky landline infrastructure—all the functionality you need comes via the Internet.
But what is a trunk line, and what benefits can it bring to your business? We’ll discuss that and more in this article.
What is a trunk line?
Trunk lines, also known as SIP trunks, can make and receive calls via the Internet, working alongside a technology called Voice over Internet Protocol (VoIP) to deliver calls.
Calls made through trunk lines have additional functionality compared to traditional landline phones. Alongside voice calls, users can set up video calls and send instant messages.
How does a trunk line work?
Trunk lines connect PBX systems to the Internet using a SIP provider. The process of making a call through a trunk line can be split into three steps. These are:
- You initiate a call on your phone system. A technology called voice data conversion converts your voice into data packets.
- Voice packets are transmitted via the Internet to the recipient.
- When the data packets reach the recipient, they’re reassembled into voice signals.
Benefits of a trunk line
So, how exactly can a trunk line help you? Let’s look at some of the top advantages of using the technology.
More cost-effective
There are many costs associated with using a traditional landline phone. Alongside the handset, you need to manage and install infrastructure and copper cables. If your infrastructure is damaged, you’ll need to pay for repairs. It’s not hard to see how these costs can add up.
When you use a trunk line, there’s no physical infrastructure to take care of. You can make uninterrupted calls, provided you have a stable Internet connection. What’s more, any errors with your system will be handled by your SIP provider.
SIP also often offers a variety of payment plans. You can find an affordable package that suits your needs.
Higher call quality
Traditional landline phones can be highly susceptible to interference. Faulty wiring, weather conditions, and conflicting signals from electronic devices can all damage your call quality. This makes it more difficult to build stronger customer relationships or collaborate with teammates.
Trunk lines deliver a higher quality of service so that businesses can communicate smoothly. Firstly, the technology cuts out physical infrastructure, making it less susceptible to external interference. Some VoIP providers also offer HD voice functionality, delivering higher-quality audio that minimizes background noise.
More flexibility
Today, businesses make flexibility a top priority. You’ll want a communication solution that can keep up with the varied needs of your team. Trunk lines mean that employees can make calls from any location as long as they have an Internet connection. That means they can stay in the loop whether they’re commuting, at a work event, or otherwise out of town.
Of course, it doesn’t just apply to employees who are on the go. More and more organizations are tapping into the advantages of remote work—in the US, around a third of workers who can work from home do so all the time.
For remote work to be successful, employees must be able to communicate as smoothly as those working in the office.
Trunk lines provide the flexibility businesses need to take full advantage of remote work. Employees can use SIP simply by hooking up to their home Wi-Fi system.
At the click of a button, they can make calls easily using a business phone number. With fewer communication barriers, your organization can build a diverse team of global talent.
Easier scalability
An organization’s needs are never static. Whether you scale up or slim down your operations, your communications solution must adapt alongside your needs.
A traditional landline system makes scalability more challenging. If you expand your office space, for instance, you’ll need to install additional infrastructure.
But with trunk lines, scalability is much more hassle-free. You can scale up or down as needed without the need to install physical infrastructure.
Instead, you can simply switch subscription packages whenever you need. For example, let’s say you wanted to upgrade to a multi-line phone system. You can do so at the click of a button.
Choosing a SIP provider
There’s no denying that trunk lines bring many benefits to businesses. But as with all technology solutions, you need to choose the right provider. Here are some tips to help you find the best trunk line solution for your business:
Consider your needs and budget
Before searching for a SIP provider, take a look at your business’s communication needs. Every organization is different and will have a unique set of requirements.
The questions listed below will point you in the right direction:
- What’s your expected monthly call volume?
- What are your communication pain points? What features would help to relieve these issues?
- How do you expect your business to change over the next few years? How will your communication needs develop?
Answering these questions will paint a clearer picture of the SIP solution that you need.
Lastly, consider your budget. Use financial data software to get a full picture of your finances. As mentioned, SIP providers often offer a variety of payment plans. What features do you need, and what is the most you can realistically pay for them?
Security and compliance
Data privacy and security should be top priorities for businesses. When you contact customers, you transmit lots of sensitive content, from contact details to credit card information. This information could do lots of damage if it fell into the wrong hands.
Globally, many data privacy laws regulate how businesses collect data. Often, these laws outline specific steps that organizations should take to protect data.
Make sure your chosen SIP provider has taken steps to protect communications data. Ensure that each call log is encrypted and that you have options to control network access.
In particular, look for certificates that signal compliance with relevant legislation. If your organization collects patient health information in the US, look for certification with the Health Insurance Portability and Accountability Act (HIPAA). If you collect data from customers in the EU, you’ll want General Data Protection Regulation (GDPR) certification.
Support multiple forms of communication
Versatility is arguably the biggest advantage of trunk lines. You’re no longer confined to simple phone calls; you can use many other forms of communication. That’s why it’s important that your chosen solution allows as many communication methods as possible.
Ultimately, you should be able to communicate with customers and co-workers using their preferred methods.
Make sure your SIP provider supports the following communication methods:
- Voice calls: It may sound basic, but you should look elsewhere if a provider can’t guarantee voice calls of the highest quality. Alongside this, make sure a solution allows call forwarding and the ability to put calls on hold.
- Video calling and conferencing: A provider should enable smooth video calling and conferencing that can accommodate large numbers of callers.
- File sharing: Users should be able to share important documents quickly and easily. File sharing should be protected with the latest encryption technologies.
- Email integration: SIP software should integrate easily with popular email providers so that users can send and receive emails from a centralized browser window.
Final thoughts
Is a trunk line the right solution for your business? That’s a question only you can answer. In many cases, SIP trunking represents a cost-effective and scalable solution. You can cut out expensive and bulky infrastructure and opt for a more reliable Internet-based alternative.
But there’s a key caveat. You’ll need a strong and stable Internet connection. If you suffer from frequent loss of Internet, a trunk line won’t be the solution for you.
If you do opt for a SIP solution, remember the points listed above. Begin by considering your communication needs, and choose a provider that puts a strong focus on data security. The ability to use multiple forms of communication is essential, so make sure your trunking solution enables versatile communication.
FAQs
What is a trunk line?
Trunk lines use the Internet to make calls. Unlike traditional landline phones, these services don’t require any physical infrastructure.
Is SIP trunking the same as VoIP?
SIP trunking is a technology that complements VoIP. SIP uses protocols that enable users to make calls across the Internet using VoIP technologies.
What are the advantages of trunk lines?
There are many advantages of SIP trunking. For example:
- This method is often more cost-effective than traditional landlines. Users can choose a payment package that suits their financial needs.
- Trunk lines are much easier to scale than traditional landlines. A user can expand their operation easily without needing to find new infrastructure.
- SIP trunking enables various forms of communication, including audio calls, video calls, and email.
Updated May 27, 2025
