It might not seem like it at the time, but buying an iPhone for full price upfront is probably the cheapest option. Swallowing the $1,000 purchase price of an unlocked iPhone X isn’t easy. However, you won’t wind up tied to carrier contracts that trap you for a year or two. Plus, you can pick a cheap, $10-per-month prepaid data plan instead.

In the European Union, Apple sells unlocked phones from the get-go. If you buy a new iPhone from Apple on launch day, it will not come tied to a carrier. In the United States, SIM-free iPhones usually go on sale a few weeks after launch.

Today we’ll look at how and where you can buy a SIM-free, unlocked iPhone.

Apple has today begun selling the iPhone 5s unlocked and SIM-free to customers in the United States. Customers can stick in any GSM SIM card (so that’s one from AT&T or T-Mobile) when they receive the device and begin using it immediately with their existing plan — but they’ll have to wait 1-2 weeks for it to ship.

The iPhone 5s and the iPhone 5c will soon be available on Boost Mobile, according to two promotional posters that have been leaked today. Both devices will be supported by Boost’s Shrinking Payments plans, but their official release dates and price tags are yet to be confirmed.

Earlier this week, T-Mobile announced that it will finally begin selling Apple’s iPhone next month, almost six years after the device first made its debut in the U.S. When you buy an iPhone 5 on T-Mobile, it will come with support for AWS bands, so that it can be used on the carrier’s LTE network.

Existing iPhone 5 handsets already in circulation don’t have this, but it can be enabled on the AT&T and unlocked models. And if your iPhone 5 is jailbroken, you can enable it yourself. Here’s how.

As of January 26th, it is now illegal for you to unlock your smartphone if you want to use it on another network. Carrier unlocking has been legal in the U.S. for years, but in October the Library of Congress ruled that unauthorized unlocking is a crime.

The Obama Administration has already voiced its opinion that citizens should be allowed to unlock their smartphones without risking criminal penalties, and a senator from Oregon just introduced a bill that would making unlocking legal again.

From Saturday, January 26, you’ll have to ask your carrier to unlock your smartphone if you wish to use it on another network. It will become illegal to do so yourself using unauthorized unlocking methods — even if your contract has run its course and you no longer have a commitment with the original provider.

The iPhone 5 is now available for purchase unlocked at an unsubsidized price on Apple’s U.S. online store. Customers should also be able to pick up an unlocked iPhone 5 in U.S. Apple Retail stores as well. Pricing starts at $649 for the 16GB model.

It typically takes Apple a couple months before it starts selling a new iPhone model unlocked. Today a new option has appeared in the online store for selecting an unlocked model without a two-year carrier contract.

Verizon sells the iPhone 5 unlocked out of the box, but what about AT&T? If you buy into a two-year contract for the subsidized starting price of $200, you’re usually not able to get an unlock until you’ve fulfilled your contract.

Buying off-contract for the full starting price of $649 is another story, however. AT&T customers in good standing should be able to get a fully priced iPhone 5 unlocked for free, but the process requires filling out a web form, sending a fax, and possibly waiting more than a week.

As it turns out, unlocking an unsubsidized iPhone 5 is as simple as restoring the device in iTunes.

It was recently revealed that Verizon sells the iPhone 5 factory unlocked out of the box. Not only can you use the Verizon iPhone 5 on another CDMA carrier, but the device will also work on non-LTE GSM networks, like AT&T. U.S. carriers will typically unlock off-contract iPhones for free, but Verizon is selling the iPhone 5 unlocked with a two-year contract as well.

Buying an iPhone 5 at the full, unsubsidized price on AT&T doesn’t guarantee that it will be unlocked, but AT&T will typically grant unlock requests for customers in good standing. The same goes for AT&T iPhone owners who have fulfilled the life of their two-year contract.

There’s been multiple theories suggested to explain why Verizon is behaving this way, but the real reason is much simpler than you would think.

It’s been confirmed that Verizon is actually selling the iPhone 5 factory unlocked out of the box, and you can pop in another SIM card to use the device on even a GSM network like AT&T. Jeff Benjamin of iDownloadBlog has already tried inserting an AT&T SIM card into his CDMA Verizon iPhone 5, and it worked!