Emlid RS3 - USA SIM Card that actually works on AT&T [RESOLVED]

NOTICE: Be patient, the wireless network will not activate right away, you may have to turn on wireless network a couple times and wait a couple minutes. Its not instant. Try installing the SIM, resetting the Reach unit, making sure data roaming is enabled, ensure the APN is entered correctly(puffin.network), and turn on mobile data, might have to attempt to turn it on more than once. Just give it a minute and after that it works great every time I turn the unit on.

I have only tested on AT&T network because it is the only one available in my area, but they were very diligent in helping me get this working when Emlid and AT&T basically said there was nothing they could do.

The SIM card needed to Run AT&T, T-Mobile, or Verizon in the Emlid Reach RS3 LTE modem may be found here:

To confirm, it’s the SIM with APN puffin.network

If anyone needs help, Reach out to Maria,
Maria Danag contact@spectrumsim.com,
You can tell her Carlo sent you, we’re like best friends at this point.

The standard SIM for spectrum on Amazon did not work for me. The SIM that worked can only be found on their website. (as of this posting)

I tested four different SIM cards, and just because they worked in an iPhone AND a hotspot does not mean they will work in the Reach RS3.

The people at spectrum said to use code “REACH” as a referral for me, and so they know what you are using the SIM for to ensure you get the right one, but I’m not sure where you put the code or how you use it.

Best of luck, and please report back if this worked or did not work for you, or any tips and tricks learned along the way.

Have a great day,


spectrumsim.com sent another SIM card to test in the Emlid Reach RS3, and it is confirmed working.
Spectrum SIM

Currently the process for purchasing this SIM card is to purchase and check out with the only SIM available on their website, and message them and let them know you need the “TAG SIM card” with APN “m2m.tag.com”.

The difference between these is the TAG is $9 per GB and the Puffin is $14 per GB.

I have had much better luck using Emlid caster instead of LoRa for larger sites.

Report back if these SIMs do or don’t work for you.

Have a great day,