Friday, March 29, 2013

HOW TO: Setup two-line phone wiring using two Ooma systems

As you may know, Ooma is a VoIP phone service provider with a slightly different business model than other similar services (such as Vonage). With Ooma you simply purchase the Ooma system up-front ($150 for their current "Telo" system), and then the actual phone service is free forever. The only ongoing fees you pay are taxes and other government fees (about $40 to $60 a year depending on where you live), but there is no cost for the basic service itself. If you are lucky enough to have an older Ooma system (called an Ooma "Hub"), then you may not even have to pay the yearly taxes or fees.

Ooma also offers a "Premier" service that provides several enhanced features, the most useful being their "Instant Second Line" feature, for about $10 a month. The Instant Second Line isn't exactly the same as having a true second line though. In this article we'll review the differences between the Instant Second Line and an actual second line, and then go over how you can setup two independent Ooma systems to get full two-line functionality and save money at the same time.

Feature comparison
First, let's review the differences between the Ooma Instant Second Line and just having two independent Ooma systems:

 Ooma "Instant Second Line"
 Two independent Ooma systems
  • Requires using only cordless phones purchased from Ooma or purchasing the Linx device to use your own phones.
  • Can place two outbound calls at the same time, but both will show as coming from the same phone number.
  • One phone number for both lines.
  • Can receive two calls at the same time through the same number.
  • Three-way calling through the Ooma service.
  • All calls go to the same voicemail.
  • Requires Ooma Premier monthly service subscription.
  • Only requires one Ooma system.

  • Allows the use of any standard two-line telephone. Creates a standard two-line wire setup that flows back through your house and is accessible through any regular phone outlet.
  • Can place two outbound calls at the same time and have them come from different phone numbers.
  • Two phone numbers, one dedicated for each line.
  • Can receive two calls at the same time but on two separate dedicated numbers (you can also have call waiting on each line allowing people to still call each line even when it is in use).
  • Three-way calling through the conference call feature of your two-line phone.
  • Each line has it's own separate voicemail system.
  • No additional monthly service subscription required.
  • Requires purchasing two Ooma systems.

As you can see, having two separate Ooma systems provides much greater functionality and flexibility than using the Instant Second Line feature. You can use one phone number for your business, your kids, or whatever and have it completely separate from the other number. Using two separate Ooma systems is essentially the same thing as ordering two phone lines from the telephone company. To top it off you also avoid having to pay for the Ooma Premier service!

The setup
Setting up two separate Ooma systems to work with two-line phones is actually quite simple. The key piece of equipment that you'll need is a two-line coupler. A two-line coupler has two RJ-11 cables that feed into a single RJ-11 jack. It combines the single-line phone signal from each of the cables and converts it into a standard two-line phone jack. One cable becomes "line 1" and the other cable becomes "line 2" on the combined phone jack. You can buy the two-line coupler at some local electronics stores or you can just order it online for about $5 from Amazon.
Two-line Coupler
The easiest way to set this up is to position your two Ooma systems near your router and connect each Ooma to a free port on your router. Then connect the two-line coupler to the phone port on the back of each Ooma system.
Wiring Diagram (click to enlarge)
You will have to experiment with the cables to determine which Ooma system is going to be providing "line 1" and which will be providing "line 2" on your combined outlet. For instance, if you know that you want a certain phone number to be your "home phone" and be on "line 1" of your phones and you want the other number to be your "business phone" and be on "line 2" then you will have to test the setup and possibly reverse the two-line coupler cables if the numbers are the opposite of what you want.

Once you have the two Ooma systems connected through the two-line coupler all that's left to do is connect a two-line (four-wire) phone cable between the two-line coupler and any phone jack in your home. Before doing this make sure that you disconnect the actual phone company's circuits from your inside wiring. This usually can be accomplished by opening the telephone network interface box on the outside of your home and simply unplugging the test jack inside. By doing this you are isolating your home's telephone wires from the local telephone company's network. This is necessary to prevent power from remaining on your internal phone wiring which will interfere with the operation of your Ooma system.
The freedom to use any one- or two-line phone!
After you have the Ooma systems connected to your home's wiring you can plug a two-line phone into any other phone outlet in your home and have access to both Ooma lines. You can also just use single line phones anywhere that you don't need access to both lines and those phones will just access "line 1".
Triple Jack Modular Adapter
If you need to also place a phone in the area where the Oooma systems are setup you can connect a standard dual or triple jack modular adapter to the two-line coupler. You can then plug a phone into one of the adapter ports and the cable that connects to the wall outlet into another adapter port.
The final setup using both a newer Ooma Telo system and an older Ooma Hub system
If you have just a single Ooma system with the Premier service you will pay the initial $150 purchase price for the system and then $60 for at least one Ooma provided cordless handset plus $120 a year for the service and $40 to $60 a year in taxes and fees (we'll use $50 as an average for the taxes and fees). Your first year cost is ~$380, with each subsequent year costing ~$170.

If you purchase two Ooma systems and set them up as described, without the need for the Premier service, then you will pay the initial $300 purchase price (for two systems), plus $80 to $120 a year in taxes and fees (again, we'll use $50 a year per system as an average for the taxes and fees, so $100 a year for both systems). Your first year cost is ~$400, with each subsequent year costing just the ~$100 in taxes and fees. Using this method you pay only $20 more the first year and then save ~$70 a year and end up with two true phone lines with their own numbers and full compatibility with regular two-line phones throughout your whole house.


  1. Thank you. This is a great post. However you still have to give out two numbers. I wonder if there is a way to give one number and use call hunt...

  2. Can you do the same sort of thing using the Ooma Linx as your second device instead of another Ooma Telo?

  3. Getting the Linx may prove to be a better option since QoS (quality of service) can be managed by the Telo, which isn't addressed in this article. Running two Telo's in tandem, as in the diagram, would require QoS to be supported by the modem/router. When I renewed Premiere service for $99 (via chat with customer service), they sent me a Linx no charge.