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by Jason Snell & Dan Moren

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By Dan Moren

SIMply irresistible: An unlocked phone is a traveler’s best friend

Note: This story has not been updated for several years.


I managed to get my iPhone 6 unlocked before going on my international adventure last week, and it reinforced a belief that I’ve held for some time: locking phones is stupid.

Yes, I know the point behind it. Companies want to sell you on their international data plans which are, no doubt, insanely profitable for them. My provider, AT&T, charges $30 for 120MB of data. 120MB. In 2015. Just to be clear, my domestic monthly data plan is 4GB for $45, so I think I’m being pretty charitable when I say that math is crazy bananapants.

I won’t pretend to know all the ins and outs of data roaming costs. Maybe it’s super expensive.

Except T-Mobile, meanwhile, is providing free international data to all of its customers, albeit at slower 2G speeds. But at least then you don’t have to worry about incurring hefty overage charges if you forget to put your phone in Airplane Mode when you’re not using it.

The Verizon iPhone, on the other hand, ships with an unlocked SIM slot, meaning that you can easily swap in a SIM for overseas travel.


I spent some time reading up on the best prepaid data SIM options for Portugal, using a couple of good resources and browsing the local cell phone providers sites (when they had English versions, anyway).

I settled upon what looked like a pretty good option: 4GB of data for use within 7 days from Vodafone Portugal. It was probably way more data than I needed for my not-quite-five-day trip, but I figured it was worth it to not have to worry about going over. The princely sum demanded for this plan?

€12.50. If you’re playing at home, that’s not quite $14.

Not only is that way better than AT&T’s international data offerings, it’s a deal I wish I could get at home every month. As someone who barely makes phone calls or uses text messages, but does consume a ton of data, that’d be a steal.

For the record I ended up using about 600MB of that data—or an eighth of my total allowance. And service in Portugal was great; I ran into no significant issues with getting a signal, speeds were great for the most part, and all of my apps and services worked a treat. Best of all, getting set up was a breeze: there was a kiosk in the Lisbon airport on my way to the metro station and the folks there helped me get set up in less than 10 minutes, start to finish.1

United Kingdom

My second stop was the UK, and my first thought was that perhaps I might be able to simply flip on data roaming on my iPhone and use that same Portuguese Vodafone SIM in the UK. After consultation with Twitter, there was no consensus as to whether a) it would work and b) there was any way I could be charged more money. Chances were it would simply chew through my remaining data a lot faster. I did flip it on briefly to see if it would work, and sure enough, it picked up the Vodafone UK network, but I decided not to risk it.

However, I did get a rock solid recommendation from my Twitter followers as to which way to go for prepaid data in the UK: Three’s £15 plan with unlimited data was the clear winner (slightly pricier than Vodafone Portugal at $23, though still way cheaper than U.S. options). And, as in Portugal, there was a conveniently located Three shop—in this case, a block away from my hotel. Set up took likewise about 10 minutes, and I walked out of the store with a fully functional phone.

Three’s service was not quite as good as Vodafone Portugal, though part of that is also that wide swaths of the London Underground don’t have any signal at all, but with all-you-can-eat data, it’s hard to complain.

Even better, as Upgrade’s own Myke Hurley pointed out to me later, Three lets you use your data from its plan in many other countries automatically, at no extra charge, meaning that in my admittedly brief layover in Dublin I still had full Internet access.

A more civilized age

In total, over the last few years I’ve bought SIMS in four other countries, all of which provided better deals than relying on my own carrier’s international plans.

So carriers are protecting their profits: nothing new there. What makes it frustrating, to most end users, is that there’s no way to know the value of the thing. In the same way that carriers have long gouged users on the price of text messages—the cost of which is negligible to the carriers—it’s unclear exactly what the value of international data is. But let’s do a little quick math.

With AT&T’s international data plan I’m paying $0.25 per megabyte of data; with Vodafone Portugal, I ended up paying $0.003 per megabyte. (That’s not a typo—we’re talking a fraction of a cent.) AT&T therefore is charging me about 83 times more.

In the end, data costs on my trip were about $37—more expensive than if I had just spent the money on AT&T’s plan, but with far more data at my disposal than I would have had otherwise.

The long and short of it is that locking phones is, as I said, stupid. Yes, it prevents you from taking your phone to a competing carrier, but with the way most contracts are structured, you now have to buy out your phone’s subsidy before you can jump ship anyway. So the SIM lock is really just an artificial block put into place to prevent the carriers from having to compete on price.

And they get away with it too—my guess is because not everybody travels internationally, many who do are uninformed about any other options, and those in the know end up quietly unlocking their phones anyway (oftentimes through means that potentially put them at risk, such as jailbreaking, or through middlemen who charge potentially exorbitant rates).

At least it’s no longer illegal for consumers to unlock their phones, thanks to a law passed last summer…though that doesn’t preclude carriers from forcing you to meet certain criteria before they unlock phones for you. Which generally includes paying an early termination fee.

It wasn’t so long ago that buying music meant purchasing files that could only be played on a certain type or number of devices. Having kicked DRM-protected audio files to the curb, I think it’s time that international SIM locking follow suit.

  1. I did end up rebooting my phone, though in retrospect, I think I actually didn’t even need to do that. 

[Dan Moren is the East Coast Bureau Chief of Six Colors. You can find him on Mastodon at or reach him by email at His latest novel, the supernatural detective story All Souls Lost, is now available for pre-order.]

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