Cell carriers, let us have more than one phone on the same number

Everybody's got old cell phones, which sit in closets. Why don't the wireless carriers let customers cheaply have two or more phones on the same line. That would mean that when a call came in, both phones would ring (and your landlines if you desire) and you could answer in either place. You could make calls from either phone, though not both at the same time.

Right now they offer family plans, which let you have a 2nd "line" on the same account. That doesn't save much money for the 2nd, though the 3rd and 4th are typically only $10 extra. That's a whole extra number and account, however.

Letting customers do this should be good for the cell companies. You would be more likely to make a cell call. People would leave cells in their cars, or at other haunts (office, home or even in a coat pocket) for the "just in case I forget my cell" moments. That means more minutes billed.

The only downside is you might see people trying to share, both the very poor, or some couples, or perhaps families wanting to give a single number to a group of kids. While for most people the party line arrangement would be inconvenient, if it becomes a real problem, a number of steps could be taken to avoid it:

  • They know where the phones are. Thus don't allow phone A to make/answer a call a short interval after phone B if they are far apart. If they are 1 hour apart, require an hour's time.
  • To really stop things, require the non-default phones to register by calling a special number. When one phone registers, the others can't make calls. Put limits on switching the active phone, possibly based on phone location as above.
  • Shortly after registering, or making/receiving a call, only the active phone receives calls.

I don't think these steps are necessary, but if implemented they would make sharing very impractical and thus this service could be at no extra charge, or at worst a nominal charge of a buck or two. It could also be charged for only in months or days it's actually used.

This is a great service for the customer and should make money for the cell co. So why don't they?


I'm not convinced that customers using more minutes wouldn't cost the providers more than any marginal revenue - after all, within my "plan", marginal minutes cost me nothing extra, and going over is so expensive that it is to be strongly avoided.

Then there is the problem that all my old cell phones are also old technology and not compatible with my current service, including a couple of analog-only phones.

Yes, many of the old phones are not compatible, but thanks to eBay, there is a plentiful supply of only slightly older tech phones that work with your carrier at a low price.

And in fact, if carriers offered this service, they could make a nice penny doing trade-ins and reselling phones. Right now they upgrade you and leave the old phone to be put in the closet, which is a total waste.

Yes, you buy a bucket of minutes, but everybody's bucket size is based on what they observe as their usage pattern. If they find their desire for minutes goes up, they consider bumping the bucket, which the carrier loves.

Finally, this would be a competitive advantage. People would consider this in choosing carriers. Some people live with their cell always on their belt, but sometimes I forget mine, and if I could keep an old one in the car for such times, it would be highly useful, and would affect my choice of provider.

but what happens if you answer both cell phones at the same time? think of all the overhead in processing that the cell carriers wil have to do in order to provide a service that's marginally useful. also, the more cell phones you have, the more likely you are to lose one. do you really need 3 cellphones when the size of the phone you have now can easily fit in your shirt-pocket?

This is not a big problem. Lots of services today offer ringing multiple phones at once. I use it myself all the time. Call my number and it rings 5 different phones (but not my cell phone because that goes to voice mail immediately if off.) Not a problem. Whoever is first wins, or if the cell company wants to, it could just have all answerers be put in a conference call and bill lots of airtime.

I just don't see how this is marginally useful? I guess you never forget your phone. If you don't, you wouldn't see the value of this, but for those who sometimes go out without their phone, or even those who leave one phone downstairs in a charger while they are upstairs, we can see the value and it's high.

High enough that they could even charge more for it, ie. if I want to use the backup phone in my car they could bill me per minute on top of my pool of minutes, and let me decide if I want to answer or make calls from it. But I don't think they need to go that far to make this a revenue generating service, and some users would decline to use it if it came on those terms.

I think with this available lots of people would put a cell phone permanently in their car, either off or under the seat wired in to car power. Then, if they went out without their phone, they would be able to fix that.

I would doubt that the additional revenue would pay for the additional costs. One opportunity cost that this would raise is a security concern, at least for analog phones: two appearances of the "same" phone indicated fraud.

Development costs could be significant as carriers try to deal with "partial roaming" calls: two phones could simultaneously ring in, say, Dallas and Sydney. Ringback is supposed to be provided by the far-end (i.e. "the" ringing phone), with the voice channel set up prior to answering: choosing which target phone is the primary, and managing timing issues among the various targets would raise plenty of development problems.

If all you want is the "ring multiple phones" service as you already have it, then, well, don't you already have it?

You overestimate the difficulty. First of all, this is not two appearances of the same phone in any way, shape or form. Many companies already offer ringing two or more lines at once for a call. It's not just easy, it's a solved matter. I can do it myself, and ring both my cell phones at once in this fashion with no difficulty, and have done this. The only thing that actually stands in the way is accounting -- to do this I have to have two cell accounts, with two monthly fees, or two phones on the same account with a high monthly fee.

The other technical items are minor. You could implement this in short order by giving the other phone a 'number' that can't be called except by the forking agent which rings multiple phones, and map its caller-id on any outgoing calls and you would be done. However, that's a kludge to get it done in a a short time, doing it right is really not that much work.

Once again this is not only doable, I have already done it with my home computer. It's mainly a question of billing and caller-id manipulations.

Again, if all you want is the "ring multiple phones" service as you already have it, then, well, you already have it.

But that's not the same as the service you describe, giving the other phone a "number" under specific calling restrictions. As I described, that's where the technical problems start, and they are not as short as you seem to believe. It's doable, but not trivial (and therefore expensive to implement, for arguably marginal return). You can choose to not believe it, but that doesn't make it easier.

Because I have to buy a full account for the second phone. If you already have a 2-phone family plan, a 3rd phone is $120/year. Otherwise you can get a prepaid phone for about $100/year but you pay for minutes.

However, we're not nearly there. If I call from the 2nd phone, the caller-id is that of the 2nd phone, not my master number. And for me to ring both phones, I have to have callers call a _third_ number which can do forked calling. This is not hard, but it's yet another number, not provided as the caller-id, and has minor costs (1-2 cents/minute) on all calls.

Finally, for me to do this, all phones must have voice mail turned off, because a phone that is off/out of range goes directly to voice mail which looks to the outside world like somebody answering the phone.

These are minor issues for the cell company itself to fix. Clearly their forker would understand phones that were off, and they can change the caller-id simply and easily.

Finally, I think they should sell this for less than $100/year, in fact I think it's in their interest to give it away, or worst case to sell it by the minute -- 10 cents/minute is a perfectly profitable rate on their home systems. I'm not expecting roaming from the secondary phones though that's not so hard to do either.

Doing this internally is easy, and many PBXs can do it internally today, correctly handling voice mail, caller ID and the like. It's really just an accounting decision. And trust me, there are customers who would like it a lot.

I take it that you continue to disagree with me as to how easy this is to implement. So, since you believe that you're right, we can expect cellphone companies to begin to offer it this spring. Or, if I'm right, they won't begin to offer it for several months at the earliest.

Want to bet on your position?

I don't believe they have any plans. That's why I'm floating the idea. There are things that are easy to do which end up being hard because the underlying systems are mucked up. Sometimes something that is just an accounting change can still be a nightmare if the accounting wasn't designed flexibly. So I make no bets about how long they would have to do it. That there is nothing inherently hard should not be a matter for debate, since it's a feature people get in PBXs, which tend to be less sophisticated than full cellular switches. Cell phone companies started out be far more innovative in terms of their switching than both PBXs and 5ESS PSTN switches.

Of course, the only things that actually could be hard to do are not actually necessary, they just would be implemented to discourage people from cheating on the system and having two phones used by two people. Charging 10 cents/minute for calls on the supplemental phone would solve most of those problems, since people wanting a 2nd fully functional phone for 10 cents/minute can already buy that in the prepaid market from T-mobile.

Do you know which service providers allow you to ring multiple phones? I would love to be able to call either of my cellphones just using one number. I don't know if it is possible with Sprint, my provider.


Such as the voip services. Since Vonage does it, and they are the market share leader, I think just about all the other voip services do it.

I do it myself by buying cheap numbers from voip providers such as, currently, icall.com, and routing the call through my own Asterisk server. Probably not for the casual user but many do it this way.

Call my voip numbers and you are actually ringing 5 different phones at once.

But not, alas, the cell phones because they go to voicemail if off, which screws it up. I tried to get tmobile to turn off the voicemail, and have not yet managed to make it work.

I was just searching the web (google: can you have two cell phones on the same line) and stumbled across your thread... Finally, someone who thinks like me. I wish they would offer this service because, yes, it would be great to be able to have an "emergency backup" phone in the car at the office, just in case I left mine at home. It happened to me today. I hadn't thought all of the problems through, but your suggestions are great (specifically the phone registration thing). Someday, maybe it'll happen... that would be SO helpful. :)

I do a lot of water-oriented sports such as kayaking and fishing. I use a Palm Treo 700p for business, but am disinclined to carry it with me in a kayak because damaging it is a very expensive proposition. Being able to use my existing number on a cheaper phone would be very useful.

This would certainly be helpful to many folks, however I believe it would make their abuse- and fraud-detection methods more difficult.
There are currently big ops which filter through masses of detailed data from signal strength, which can be (and presumably is) sifted
to find patters for abuse. For example, what appears to be the same phone suddenly appearing on the network, at a reasonable geographical
distance from the "active" phone/device. It seems that those operations would have to vectorize as it were and further invade the privacy
of consumers to maintain their attempts to protect their business.

The tools (hard & soft) to basically "clone" a phone, would be handy for plenty of Fair Use situations,
although I guess stopping by the kiosk isn't a big deal.... story: I just had a friend whose phone broke in half, and
although she could still read her phonebook off it, she needed a replacement... I wanted to offer her either
of two older models I have here, but, difficulties ensue, as you might know about the abundance of incompatibilities in SIM cards and so forth.

These problems are in fact an SEP (not my problem), and I'll hope along with other readers that good market competition along with DIY culture
and open source innovations will spur enough positive changes for all users, that we'll be enjoying a really enabled tomorrow with appropriate
technology trumping bad implementation. I enjoyed reading your article, 'Replacing the FCC with "don't be spectrum selfish"', and appreciate
the directives therein, however it is nearly impossible to explain invisible things to people :) I suppose the more reasons there are to care,
the more attentive and imaginitive the public's reception of and response to RF issues will be.



The two phones would not look at all similar, would not have the same serial numbers or imeis or anything like that. They would be two completely different phones. The "joining" would be in the network, so that both phones ring (if both on) for calls, and calls from either phone generate the same caller-id. And of course, special billing.

This could even be implemented with the second phone having its own number that's not used for any outside purpose, other than making it easier to implement things.

Again, let me point out that you can already do this today on your own, with two exceptions. First you need two accounts (ie. it's twice as expensive) and second a call from the 2nd phone would not send the caller-id of the first one, unless you used a fancy call forwarding app. There is absolutely zero issue related to phone cloning.

Well its definitely easily possible in voip services but GSM has certain limitations while registering in HLR, which can be overcome if the cell provider realy wants to, regarding the cloning part of it i would not buy that point as IMEIs are something that can be reprogrammed and hence this is a major issue i you want to monitor clonning, i wrk fr a telecom fraud team and hence i am aware f it. But still feature is some thing very consumer friendly.

The other comments on this subject all seem to be written by those folks that ALSO have a wired land line. I just got ordered a new cell phone and account with Alltel. My goal is to completely rid myself of all things Sprint, including my land lines. I thought I could just use a cell phone alone but eventually, it dawned on me that depending upon just one phone was folly. I want at least 2. This does not mean I'll use them both at once, but at least I'd have a spare in the event that my main cell phone dies. THAT would make me feel a whole lot more secure. I just got off the phone with Alltel and was told that I could not do this but they'd be happy to sell me another "line" for a mere $20/month and I could pay retail for another phone just like the one I ordered. By my math, that's $240/year plus the phone - a quarter of a thousand dollars + and I do not WANT another line - JUST another physical phone device.

Why must I be forced into this corner? You know it's a scam and that the cell people are making large money by doing this or perhaps more accurately, they fear they'll not make as much should they implement a policy allowing a second phone. Perhaps they are right - just think of the nasty things they COULD do, like keep track of which phone you are making your calls from and charging one a premium for using that spare phone - kind of like roaming charges. In fact they could even charge actual roaming until the customer gets around to calling in and explaining why they are on the "other" phone or some such plan. I am sure they could cook up something. Surely using 2 identical units might be a restriction? I can see why you can't use an older phone or dissimilar model.

By instituting this stupid rule, they prevent at least me from going completely wireless (cell) so I'll keep shipping Sprint money each month (grrrr) instead of handing it to the cell carrier (NOT Sprint - no way). In my case, they'd make money. I can't speak for others but I want the peace of mind of a backup device just in case. You DO back up your important data on your computer - don't you??


T-mobile's prepaid service offers a deal unlike any I have seen anywhere in the world. With their prepaid service, once you have put $100 of airtime into the phone (which gets you 1000 minutes if you do it at once) then that and future airtime lasts for a year.

This means you can keep a GSM phone alive, if you don't use it much, for $10 per year, after you've put in the initial outlay. Frankly, even $100 per year is a decent deal which you can't get from other carriers. (Virgin Mobile USA will do it for about $80 per year.)

So that's great for a second phone, but it's still not what I propose here, which is a second phone that works on the same account, and rings on the same number.

I think Tracfone has the same deal that you describe at T-mobile.

Also, any network using GSM/SIM cards would let you own two, or more, phones and swap out your SIM card as needed.

The trick is to avoid losing the SIM card, of course.

Tracfone does have a 365 day card, but it costs almost $100 and only gives you 400 minutes. T-mobile's deal is vastly superior, not just because they give you 1000 minutes on the $100 card, but because after you have done this, all refills last a year. So you can put in $10 *a year*, not $10 a month, after that. I have not seen anything like that anywhere in the world. It's so much better than other deals I wonder if it will last forever.

Sadly, you can't get data service with it. I'm actually a light cell phone user. If we're going to have a long chat, I prefer to be on a landline for better quality (as well as lower cost.) However, since I want a PDA phone with data, I can only use T-mobile to-go for my 2nd phone.

However, if you have old GSM phones, get a T-mobile SIM and set it up this way, then get a VOIP number to ring both your main phone and that one (you must disable voice mail on both, which takes work) and you can almost get what I describe, but you still will send the caller-id of the phone you use, not the master number.

yea....if you have verizon, and log into my account (which is free) you can do an ESN swap when ever you want online...so you keep an old ohone at the office or car....if you forget your phone at home simply log in, type in the ESN number located on the back of the phone under the battery and reset the phone...viola! the old phone now rings your number! when you get home that night just switch it back! all free!

And how am I supposed to do this procedure (which is really not so simple) from my car when I am driving down the road and realize I left my phone at home? Even if I had web access on the phone it would be disabled so I could not do this. Nor could people call me until I realized I had forgotten the phone. This is really a poor substitute for what I want, and what I want is not that hard.

any questions...go to verizons website lol

Ok....so I have this older phone that doesn't have a slot for a SIM card but i really like its a tough phone but i was forced to switch to SIM cards and the phone has just been sitting around. Is there any possible way that i could use the old phone and my new phone that has the sim card and have them both be on the same phone number? Is that even possible? I mean the one phone is that old that it doesn't have a sim card slot...and if i could have both would my sim card be hurt in any way?

and they don't provide it. You could get a number with a service like Grand Central (Google) for free and then have it ring both phones when people call it. Get a T-mobile prepaid SIM for 2nd phone.

grandcentral.com by google will be offering this "switch boarding" service soon. So you could just do a family plan and add an additional phone and have grandcentral forward all calls to your 2nd phone at the same time it rings on your main line.

I have a couple of cool landline phones at home. One is a "portable" and the other has speakerphone capability and both have all kinds of programming features. So, I don't just want to have multiple ringing cell phones, I want land-line type phones that operate from cell signals. It's the form factor of the "home" phone that I like. The only reason cell phones are so small is that you carry them around. One that wasn't carried around would not need to be so tiny. I would get rid of AT&T in a heartbeat if, for the combined price of AT&T and Verizon I could just have cell service--but with home units that had landline phone size and features. I want it all, dammit!

I bought a Virgin Mobile pay-as-you-go phone in August. I recently lost it for around 3 days, and in the interim, thought it was gone for good. So I bought a slightly better phone with the same company. It would be nice to have two with all of the same information stored on them, in case one is temporarily misplaced, stolen or destroyed.

I know this is a dead thread, but I stumbled across it and I think it would be great to have an "extra" phone to use if my fancy scamchy smart-phone dies, runs out of battery, or gets run over by a rampaging donkey.

I personally would find the two phone/one number thing very useful! Right now I am interested in purchasing the new droid phone, however, I recently found out that the droid does not allow tethering. I use my current phone to tether a lot since I travel for a living. If I had two phones to my same number, I could use my old phone to tether and my new phone for everything else

I have a DockNTalk, which is a device that allows you to dock your cell phone usually by bluetooth connection so that you can make and receive calls from multiple land phones connected into your cell phone instead of into the land phone company jack. If you have wall phone jacks that aren't connected to the phone company you can then connect the dockntalk into a jack and have I believe up to 5 wall phones ringing at the same time when someone calls your cell phone and 5 people can be talking to each other on those phones at the same time just like a landline (which wouldn't happen if you had more than 1 cell phone with the same number, unless I'm wrong about that.)

Now there are other docking stations you can dock your cell phone too. Some dock multiple cell phones, the dockntalk I own doesn't. Just google "dock cell phone" and see what device would work for you. They are kind of expensive. The dockntalk requires a bluetooth adapter for bluetooth phones which is also kind of expensive (mostly all cell phones now only connect to it via bluetooth) and another expense with dockntalk is everytime they have a firmware update to support newer cell phones -- which isn't that frequent, you have to send it back to phonelabs and pay them to do this. Although, this pales in comparison to the expenses you would incur if you had multiple cell phones with the same number -- each with their own monthly fee attached.

Really make sure your cell phone can dock because my old moto krazer couldn't with the dockntalk -- it would drop the voice so the other person couldn't hear you, my older moto worked fine but that didn't allow for caller ID; my samsung and my blackberry curve work fine with caller ID.

I used to use a cellsocket that basically did the same thing and you'll see that when you google, but this is pretty old tech and all new phones won't work on that.

I know this doesn't completely resolve the issue since this requires a power outlet to function (you may find one that doesn't) and you're not using multiple cell phones to talk on (just multiple connections using one cell phone), but you could take your docking station with you along with a few cordless phones and then have "more than one phone on the same [mobile] number."

The goal is to have only one cell phone account, and to be able to use the old phones when you forget your main one.

That includes forgetting to put your main one in the dock.

I was in Europe in 2008 and their carriers have "Twin" sim cards. One in your phone and the other in your car. If you forget your mobile at home and someone calls your ONE phone number it still rings in your car. The technology/method exists. Question is where is it in the great USA? Anyone know?

See description at this site.

They are actually giving you two seemingly cloned SIMs. It seems to only ring one at a time, depending on which you called from last. (It says it also depends on where you received a call last which is harder to fathom.)

Ideally I would have it so that it always rings them both so you don't have to do anything explicit to switch. Of course telcos will want to be sure you are not sharing the phone among two people, so I can see the need to make an explicit switch though they could also just limit the number of switches (ie. where you call or receive from) but always allow all to ring.

I think moreso than having a second phone for emergencies in ur car or office would be for people like myself that work in maintenance and need my phone to check emails for repairs, log onto my jobs network to edit and close open requests.. I work in dust, water, gas, oil etc.. I have a blackberry right now and its only 4 months old and is basically ruined, barely works right.. It would be convenient for me to have say a windows based device that I can use for work and then my blackberry or an htc evo @ home for personal use.. I'm trying to have my company get me a paid work phone, then yeah I can probably do call forwarding.. I'd rather have one phone# for everything... Couldn't they just make it so that if both phones are on they both simply just don't work.. Basically when I get home from work I would shut my work phone off in order for my personal phone to be active and vice versa!? That would be amazingg!

hey i just got a new phone because my old samsung vice screen broke, but the funny thing is, whenever my new phone gets a text, the old vice will also ring. two phones, one number.

Everything mentioned above to try to explain why the cell phone companies do not allow more than one phone per number is ridiculous. Software can take care of all the arguments.

But what is missed is the real reason to allow more than one. If you give up your home land-line so as to use your cell phone 100%, you must carry it constantly and everywhere in your house. And the wife does not have any access unless she has her own separate cell phone. Carry it to the garage, to bed, to the shower. If you leave it on the charger in one room you cannot answer it anywhere else.

Remember 20-30 years ago when the land-line companies pretty much did the same ? Only they could install an extension and the phone could only be bought from them. Now it is the cell phone companies doing nearly the same. They control everything about the cells.

Hopefully some day their ignorant rules and regulations will go the same way as Ma Bell.

You can get home portables where the base station acts as a Bluetooth headset to your cellphone. So you just plug your cell into the charger next to the base station and then use any of the portables you have scattered around the house (e.g. Panasonic allows up to eight.)

I totally agree you have it layer out functionally but is have to careful of the federal law. What I would want is to take my old basic reliable phone when my current phone isnt good or on a trip and such. To switch them quickly

Just get CDMA workshop and clone it yourself, fluck the cell phone company.

Not having this capability is the main reason I don't get rid of my land line for real and get a nicer cell phone. landlines can be in different rooms at once and if one handset dies/runs out of batteries you have the other one. It would be soooo handy if a cell phone had the same type of functionality. Paying for the second handset in full and paying 10 dollars extra a month or whatever to be allowed to use the second handset would be fine... I would be willing to pay a fair bit to be able to finally junk my land line without losing its many conveniences. gettinga second line so that I have to give everyone a new phone number is both expensive and inconvenient and comes with a lot of things I just don't want.

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