We’re getting ready to be away from the U.S. for a year beginning in, um, just a few days, and we’ve left this until the last minute. As I sit in a coffee shop with my two daughters and a niece, all of us perched in our comfy chairs and tucked into our electronics, I realize we need to figure out what we’re going to do about our all-important phone devices while we’re overseas.

We already know that one of our phones will not work overseas at all. Most U.S. cellular phones work on the CDMA network, whereas most of the rest of the world is on the GSM network. CDMA phones will not work on the GSM network. In order to have a phone that will work overseas, you will need a “world phone.” I have an iPhone 4S, which CAN be a world phone, but it was not shipped that way from Sprint. I called them and told them where we’d be, and they unlocked it for me, which required connecting it to iTunes for an update.

Having the phone unlocked, I will be able to use it overseas through Sprint, but upon further investigation, I discovered many less expensive ways to use it. Purchasing a SIM card in each new country we go to is a possibility, but in each new country I’ll have to find a place to buy one, and each one will give me a new phone number. And in some countries we’ll only be there for a few days at a time.

The best option for us seems to be a World SIM card, which gives us a single phone number for use in many countries around the world, and even offers data at a much lower rate than Sprint. The main downside to this is that they all use a technology that requires, when making outgoing calls, calling a central number and then receiving call back from them when your call is connected. It sounds a little like calling the international operator of old. But if it gets us a 49-cents-per-minute rate instead of $2.49, I think we can live with that.

The three main providers I looked at are Brightroam, OneSimCard, and Telestial. Each has slightly different coverage and rates, as outlined below. Honestly, I don’t use my phone as a phone all that often. I want to be able to make an occasional local call for reservations or information, and to receive texts. I’ll use Google Voice and Skype for calls home. I wanted a local US telephone number if possible, both so that family could call me on a domestic number and so that Google Voice could reach me (though it remains to be seen if this will work!).

Brightroam

Card cost – varies – some free

Incoming calls – from 0.69

Outgoing calls – from 0.49 in 95 countries

Incoming texts – free

Outgoing texts – from 0.49

US number available? – NO – UK number only

Data – 10MB/month $40, 50MB/month $100, 200MB/month $200

OneSimCard

Card cost: $29.95 +$5 for micro-sim

Incoming calls – free in 150 countries

Incoming texts – free everywhere

US number available? – YES – $4.99 setup fee, $19.99 per year

Data – $2.49 for 10 MB day per 24 hour period in Europe

Telestial

Passport card – $19 includes $10 credit

Incoming calls – free in 75 countries

Outgoing calls – from 0.49 in 95 countries

Incoming texts – free

Outgoing texts – from 0.69

US number available? – yes – both UK and a US +1 number are offered

Data – from 0.49/MB – depends on country

For me, Telestial made the most sense (and they had the least expensive overnight shipping, at $24.90 – key for Mrs. Procrastinator). I’ll update this post when I’ve had a chance to use it.