Prepaid 4G Data Sims

From time to time we get inquiries from folks traveling to the US from overseas, or just in a mode where they need to use USB modems on a temporary basis and want to buy their data on a prepaid SIM.  I just went through all the hoops associated with this on both Verizon and AT&T so I thought it was a good time to share. This isn't the only way to get it done, but I found that if you go into a shop and ask for a prepaid USB modem account, you'll be met with a blank stare and a couple of hours of confusion.

First, you'll really want to invest in a modem for the particular network you're targeting, in order to avoid high costs and diversions to 2-year agreements. Ebay is your friend here. For Verizon, always choose the UML295, as it's the only USB modem to support their XLTE band. For AT&T, either the Aircard 313U or the "Beam" will work well. The Beam is a bit nicer because the display on the modem will give you your data balance. If you choose the Beam, be sure to update its firmware on a computer, as Comrex codecs now only support the latest.

Expect to pay around $50 on Ebay for each of these modems.

The approach from here depends on the provider:

Verizon

By far the easiest way to get prepaid data in Verizon is to carry a Verizon-capable iPad (or Android tablet) into the store. Borrow one if you must. For $50, they will load it with an LTE SIM with 6GB of data attached, enough for several days of audio codec and several hours of video codec use. If you use an iPad, you'll probably need a SIM adapter to fit the Apple-centric "nano" SIM into your UML295 (which uses a micro-SIM). Adapters are available at the shop or easy to get on Amazon.

With Verizon, the alternative is to get a "Jetpack" hotspot SIM (again, Jetpack hardware is cheap on Ebay) and move that to the modem. You'll probably need to cut that down to fit the micro-SIM format. For some strange reason, prepaid hotspot plans are more expensive ($60 for 3GB) than iPad plans.

Make sure your SIM is active and working on your "dummy" device before leaving the store. Also, make sure it uses LTE, and isn't locked to 3G for any reason.

Verizon will always get you for a $35 activation fee for a new account.

AT&T

AT&T iPad SIMs don't work in modems (learned that the hard way). You will need to buy a prepaid hotspot SIM here. But the cost is the same ($50/5GB). AT&T is more open about devices, so the store reps should have no trouble getting your account going directly on the USB modem (just make sure to bring your laptop). Like at Verizon, make sure your modem is running in "4G LTE" mode, and be aware AT&T offers "4G" without LTE which is slower (and which you don't want to be locked into).

Tips for both

1) Make sure they are putting you on a prepaid plan, and not a monthly one (which is different still from a post-paid contract plan). With a monthly, you are subject to overages, and you might not like the results.
2) Make sure your plan doesn't auto-renew (unless you want that). It seems that until recently, auto-renew was the default. But both the Verizon and AT&T plans I got were set to "non-auto renew" by default.
3) Using your SIM's phone number, you can create an account online and recharge your SIM whenever you want. Unused data disappears one month after you load it, so only buy what you need.
4) If you don't reload your card for three months, the carrier will deactivate it and you won't be able to reload it anymore. You'll need a new SIM. At AT&T, this is free, but Verizon charges $35 to activate a new pre-paid account.
5) Remember that if you prefer, you can always leave the SIM in your hotspot or tablet, and tether to your codec via Wi-fi. Note that not all tablets support this on all networks, so do your homework first.