Business Phone Lines (POTS) and PRI still account for the majority of the voice communication going on in business today. Most businesses start out with POTS, or business phone lines, until they graduate to PRI.  This article covers the benefits and limitations of both services and when it is a good time to convert from POTS to PRI.

Differences Between Business Phone Lines and PRI

business phone service

Business Phone Lines, also known as analog phone lines, are individual phone lines that can be used by a business. They are delivered over twisted copper pairs by phone companies like CenturyLink, AT&T, Verizon and Integra.

A business phone line has its own supply of electricity, allowing it to function even during a power outage.  Each business line has its own individual phone number.  In a POTS environment, if you hire a new employee and need a new phone number, you need to order another phone line.

When it comes to State and Federal taxes, business phone lines are the red headed step child of telecom, .  A typical business phone line costs around $30 a month but that figure escalates to $40 to $50 when you add all the taxes and surcharges.  If you have eight business lines, the taxes and surcharges alone could be as high as $160 a month.

POTS lines are also the target of third party billers.  Third party billers are the ticks of telecom.  If you substitute your dog for your phone bill, just imagine the way you feel when you discover a tick on your dog.  That’s the way you will feel when you come across an erroneous third party charge on your phone bill.

First you’ll want to know what it is for (never anything you’d want) and how long you’ve been paying it (probably months) and who ordered it (probably you but never on purpose).

Business Phone Lines and DSL seem to be the most economical solution in the beginning.  You’re quoted a low dollar figure for the monthly service and it seems very reasonable.  Then your first bill arrives, with all the add ons and the install charges and somehow the $200 bill you were expecting turned into $600.

Another thing about Business Phone Lines: they seem to multiply.  I don’t know how many clients I’ve met with that had lines and numbers that they don’t remember ordering and didn’t know if they used.  They end up needing their phone vendor to test each phone line to determine which ones they use and which ones to disconnect. Whereas obtaining an easy business phone number helps you to manage your business more professionally.

PRI is a more advanced business phone service.  It’s a circuit that delivers the equivalent of 23 phone lines to a business.  It allows for the use of DID’s, which are phone numbers that share the channels or call paths on a PRI.  With PRI, a business can have more phone numbers than call paths.  That practice allows a business to oversubscribe their PRI, meaning having more users than call paths.  This works, because in most businesses, the employees don’t all use the lines at once.

PRI’s cost between $400 and $500 per month.  You need a  T1 card in your phone system to utilize a PRI.  The surcharges and taxes are substantially less on a PRI than they would be on 23 POTS lines.  For instance, the CALC charges for 23 POTS lines in Phoenix, AZ would be $139.61 per month.  They’re only $30.35 on a PRI.

At what point should a business with POTS lines graduate to PRI?  When the business requires more than ten POTS lines.  It’s simple math, eleven phone lines would cost at least $440 a month and a PRI is right about the same amount, but the PRI is much more functional.

Why do businesses hold onto their business phone lines much longer than they should?  Probably the number one reason is that they don’t want to enter into a term agreement.  Most likely though, they’re already in a term deal and don’t know it.  Some providers, like CenturyLink, offer lower POTS pricing, with some sort of termination liability, but don’t require a signature or paperwork.

Another reason businesses hold onto their business lines is that they only remember the price quoted to them for the service and base all their future cost comparisons to that amount.  Meanwhile that figure doesn’t exist.  They’re not including all the tax and surcharges and the subsequent rate increases.

A third reason a business will hold onto their business phone lines (POTS) is that they don’t have a person to maintain their phone system.  POTS is simple and any other technology could seem too intimidating to someone with only a basic understanding of telecom.

Businesses should develop a relationship with a telecom agent.  They can help a business understand what’s what with their current services and bills and compare that to what’s available.  An agent has experience with multiple phone system technicians and could recommend one, should a business be looking for one.

A bad idea would be to ignore the back pages of your phone bill and keep paying it month after month.  Ignorance is not bliss when it comes to telecom.  Know your services, what you’re paying and your alternatives.

Final Thoughts

The decision between business phone lines and PRI (Primary Rate Interface) technology depends on factors like scalability, reliability, and cost. Understanding these differences helps in selecting the best option for your organization’s communication needs. Whether prioritizing simplicity or advanced features, informed decision-making ensures your business stays competitive and efficient.

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