Choosing the best SIP provider for your business can impact more than just your bottom line. The quality of your calls, the types of customer service you can deliver, and even the success of your marketing campaigns can be impacted by your SIP service. 

But selecting the best SIP provider for your organization can be confusing. Since SIP is a protocol, aren’t the offerings basically the same? Not quite. Key differences lie in who owns the network, the quality of support, and the cost and range of service options.

The SIP trunking industry in 2024

As the world reels from the waves of the pandemic, more and more businesses are looking for ways to improve their communications and flexibility. 

With hybrid and the work from anywhere on the rise, employees are away from their organization’s on-site networks, PBXs, and connections. This is driving communications’ digital transformation, and enterprises shifting from on-prem to cloud-based communications should consider the following when selecting a SIP provider. 

Seven criteria to evaluate SIP providers

According to Gartner subsidiary, SoftwareAdvice.com*, purchasers of SIP services base their satisfaction with their service on the quality of their:

1. Network reliability and quality
2. Support
3. Pricing and rates
4. Geographic coverage
5. Number availability
6. Scalability
7. Emergency services

Each of these categories is handled differently by different providers, but there are some baseline requirements that every business seeking a SIP provider needs to consider.

How to choose a SIP trunk provider

Use these seven criteria to evaluate a potential SIP provider.

1. Network reliability and quality

The most important aspect of your SIP trunk is the quality of the network that supports it. As part of the coverage each supplier offers, it’s also important that the quality and latency of your calls are as good as if you had an office right next door. Therefore, your SIP provider should be a Tier 1 carrier. A Tier 1 carrier owns the network and is directly accountable to you (getting you as close to the PSTN as possible).

Most SIP providers are resellers. They are Tier 2, which means they buy their SIP service from a carrier, or even Tier 3, which means they’re a reseller that buys their SIP service from another reseller. Those levels of distance from the original carrier create a lack of accountability. When clients of a Tier 2 reseller open a support ticket, the Tier 2 reseller can only call the carrier and open a ticket of their own. In the case of a Tier 3 reseller, the first reseller opens a ticket with another reseller, who then opens yet another ticket with the actual carrier. The customers of Tier 2 or 3 carriers can never directly contact the company that is responsible for resolving network issues.

When your provider owns the network, its support department is able to respond to your issues immediately. If you have a problem, the support personnel are already aware of it because it happened on their network, and they are already working to restore your service. 

So remember to: choose a SIP trunking provider that is also a Tier 1 carrier.

2. Support

From a customer’s point of view, the quality of support sets one provider apart from another. How quickly a support ticket is handled, and how well the issue is resolved, can make or break your relationship with your own customers.

A good support team should have an acute focus on operations and be committed to customer success. Look for a provider with a customer service department that is organized around support functions, such as network outages, billing, local number porting, etc. These providers will have support staff that is specially trained in each type of problem and therefore has the qualifications necessary to either immediately resolve your issue or to quickly recognize that escalation is needed.

In addition to being able to reach a first level expert who is trained to resolve your particular problem, you should also have the power to escalate when you feel an escalation is necessary. To that end, look for a provider that gives you access to higher level support managers. 

Lastly, read and understand your service level agreement closely. Be sure that you are getting the best support the industry has to offer, because if your phone service goes down, your business is suffering. 

So remember to: look for a Tier 1 carrier and ask if they have customers with service needs as great or greater than your own.

3. Pricing and rates

Pricing of SIP services can vary greatly, and many providers offer rock-bottom rates. However, your phone service is your connection to your customers, so shopping based solely on price can backfire. 

Uptime and reliability should be considered, too. Some traps that can raise prices are setup fees and monthly fees. Your provider should set up your service for free and your fees should be defined in your contract. You only want to pay for what you need, so look for a provider that offers multiple plans so you can choose one that fills your needs and no more. Most businesses need unlimited calling, but companies without significant long-distance needs will save more money by choosing a metered trunk. 

Typical plans offer options such as international and toll-free calls at good rates, operator services, and enhanced 911. 

So remember to: look for multiple plan options so you can choose one most suitable for your needs. Choose a provider that has flexible plans that serve your needs. If you require toll-free service, make sure that it’s included.

4. Geographic coverage

You know your business and its geography. Make sure that your plan matches your customer base.

A SIP provider that has rate centers around the US can provide the best geographic coverage. A rate center determines the boundaries for local calls, so a provider with many rate centers can provision local numbers for you all over the nation.

Rate centers determine the area codes and prefixes of your phone numbers, so using a SIP provider with many rate centers allows you to select geography to associate with your number. For instance, maybe your sales department is located in Los Angeles but you want a local area code for your Boston market. A provider with rate centers in both areas can give you that Boston number. Or maybe you’re relocating parts of your company to a new region but do not want to change the phone numbers on your marketing collateral; in that case, you need local number portability, and a SIP provider with many rate centers can provide that. 

So remember to: seek a company with robust global coverage and be sure that your provider can grow with your business’ geography.

5. Number availability

The first question you should ask your prospective SIP provider is whether they support number porting. Porting is the ability to take your number with you, and whether you are simply moving your existing numbers to your new provider, or moving sections of your business after you’ve signed a SIP contract, your SIP provider needs to let you take your existing numbers with you.

You also want the ability to get new numbers quickly. Your SIP provider should have a nationwide inventory of phone numbers that can be activated and automated in a short time span to meet your changing business needs. 

So remember to: be sure that you can take your existing numbers with you. Find out if the SIP provider can offer numbers that meet your requirements, and ask whether both new and ported numbers are serviced.

6. Scalability

As your business grows and expands into new territories, it becomes more and more important to control your operations without creating extra work. A good SIP trunk provider will give you the ability to control your communications stack in every country you’re present in, all while supporting you from your initial setup to implementing new features and working with APIs. 

Regardless of where your business is today or where it’s going tomorrow, using these qualities to assess a potential SIP provider can help you prepare for long-term success. Find a provider who can grow with your company by adding trunks and phone numbers on demand. How fast you can get additional trunks added will depend on your provider’s responsiveness, so choose a provider who can add a trunk in days, not weeks. Also, your provider should be able to install and tune your new SIP trunks remotely with no impact on your business operations. 

So remember to: find out how quickly your requests for additional trunks will be completed, and be sure your provider can add trunks remotely.

7. Emergency services

Enhanced 911 (E911) is a standard business need today; in 22 states, E911 is required or soon to be required by law. Your SIP provider should be able to deliver all calls to a local emergency call center, along with location information about the source of the call. 

So remember to: know the E911 requirements of your state when you begin searching for a SIP provider, and look for a SIP provider that can service E911.

Start searching for your perfect-fit SIP provider

You’ll get the greatest benefits from your SIP trunk if you lay a strong foundation by choosing a high-quality provider with a knowledgeable support staff that can fix problems, not just open tickets. Your plan needs to suit your geographic needs: be sure you can get the numbers you want with the area codes that make sense for your business, both now and in the future.

Your SIP trunking service has to be able to grow with you. That’s not a technology issue—SIP trunks are easy to add—but you need a provider that can handle your change requests promptly. And don’t forget the enhanced 911. E911 may be a law in your state or it may not, but if there’s an emergency at your location, you want first responders to be able to find you as fast as possible.

Lastly, your plan has to support your spending strategy. Look for value, but don’t just buy the cheapest plan: those savings will cost you money and your reputation if your provider’s support staff can’t resolve a problem that keeps your customers from reaching you.

Learn more about our global SIP

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* Harris, Daniel. Top Considerations for Selecting and Implementing a SIP Provider. Industry research, Stamford. Software Advice, 2015.