Requesting clarification about Librem 5 with T-Mobile U.S.A

I know that over the past few years there have been a few discussions here about using the Librem 5 under T-Mobile in the U.S. However, I admit that even after reading all that, I’m still slightly confused about this topic. Therefore, before I purchase a Librem 5 now (it’s currently early October in 2023), I want to make sure of the following …

I use T-Mobile here in the U.S., and I want my phone to work better than 2G or 3G. Right now, my existing phone (a Pixel 7 Pro) has no trouble accessing 5G and utilizing VoLTE. If I switch to a Librem 5 and use the same T-Mobile account, will I indeed be able to get the same T-Mobile 5G and VoLTE capabilities that are currently available to me with my existing phone?

Or on the Librem 5, will I have to settle for a lower level of T-Mobile U.S. service? By “lower level”, I mean things like less 5G availiability, slower connection speed, less VoLTE capability, etc. than I currently am able to avail myself of.

Thank you in advance for any clarification that any of you might be able to supply.

1 Like

You definitely will not get 5G as the L5 modem only supports up to 4G.

However, you will be able to have 4G internet right off the bat.

Now, you will likely need to set up the APN in both the OS settings and in Chatty app settings to get MMS to work well. T-Mobile makes that information available if you search “T-Mobile BYD.”

Lastly, your modem firmware will likely be up to date if you are ordering now. But you may need to install the bm818-tools and enable VoLTE to have usable call functionality.

Hope that helps!


Thank you very much for clarifying!

I can confirm that T-Mobile with 4G works for me with the L5. It is quite seamless. performance is pretty good. I tend to have occasional problems restoring from suspend mode because I use Mullvad VPN. Sometimes I have to cycle the kill switch for the modem. It isn’t all of the time. Just occasionally.

But, the seamless part is I haven’t quite transitioned to using the L5 as my daily driver. So, I’ll keep using my pixel 4a. But, when I feel like using the L5, I pull the sim card out of the pixel, make sure the L5 is turned off. insert the sim card. Turn on the L5 and then I’m automatically working on the L5. If I’m expecting to have some critical calls or texts, I turn off the L5. pull the sim out, and insert it back to pixel. IT works pretty seamlessly that way.

At this point, my biggest hurdle seems to be the MMS. When I was using the L5, it seemed like someone sent me a contact card, and photo, and I didn’t get them on the L5. I read up on the steps to get MMS working, but then I also learned, the MMS doesn’t work if you use VPN?! That isn’t purism’s fault, I think it has to do with the modem drivers, etc. So, I’m still trying to decide whether or how I can switch to L5 as my daily driver. I would say, I’m about 95% of the way there.

Oohh, I have come to realize, my phone call quality and reliability tends to be a little better with the Pixel, but that is because I can have wifi calling on it. That is not an option (as far as I know) on the L5. I should also mention I use grapheneOS on the Pixel. Again, with a couple of exceptions, I think the L5 could be my daily driver today.


Thank you very much for the further clarification!

I thought of a follow-up question:

If I purchase the latest Librem 5 which supports 4G for U.S. T-Mobile, and if in the future, there’s some sort of Librem 5 upgrade which will then fully support U.S. T-Mobile 5G, will there be a way to upgrade my currently owned Librem 5, or would I have to purchase a whole, new Librem 5 device if I want that 5G compatibility?

One thing I’ve noticed in threads about T-Mobile vs other services, It seems to be the only one that works in the U.S… Other threads show that other providers deny service, either outright or they are just clueless what to do with the L5.


I’m on T-Mobile myself and I have yet to setup my device but I think I heard it’s only 4G but I don’t know yet until I get the phone up and running

1 Like

The modem sits on a separate M.2 card, so it is possible to upgrade to 5G card if Purism finds a modem and provides the firmware support for it.

The other cool thing is that Purism currently supports some international modems. From my understanding, if you are traveling to other areas of the world you can get the corresponding modem card from Purism, pop in a SIM card from that area, and have a functional phone (so long as the carrier supports BYD that is) without roaming. The thing to keep in mind with that is the antenna cables connecting to the modem cards are delicate, so there’s a risk of severing them and having to do more work to repair it.


Possible with the concerns that 5G might increase power consumption and hence reduce time between charges and that the antenna might not be suitable for 5G. (In either case really I’m talking about “real” 5G i.e. 5G on much higher frequencies with much higher bandwidth, rather than 5G on basically the same frequencies as 4G.)


Yup. Worked outta the box for me with Data 4GLTE, Voice , and messaging. I then utilized the bm818 tools as mentioned in this thread for volte. Other than that it is running well. Also, I’m overseas using it.


4G cell service should be all you need for the forseeable future. Too many people get hung-up on thinking they need the latest and greatest technical capabilities, when they will never miss them. Ten or twenty years from now when everyone is using 10G (or whatever they call the latest protocol then), the powers that be might get around eventually to obsoleting 4G.

A few weeks ago I noticed that my company laptop is only running Office 2016. OMG! , what a crisis (not really), I could be running Office 2021. Do I really care? Not really. But, but, but… my current version is seven years old. My point is that I wouldn’t have even known if I didn’t look it up out of curiosity. Have I upgraded it yet? Nope. Do I care? No, not until there is something I need that I can’t have without the upgrade. 3G cell service worked just fine until a year or so ago. That 3G protocol is more than ten years old. 5G service is only available in certain conjested parts of some cities now. It’ll take several years from now before 5G even works in most places. Right now, 5G is more of a marketing byzz-word than an practical upgrade.

So whether you have an old Android phone or a Librem 5, there is no reason to even think about 5G right now. On your Android phone, most of your apps are going to quit working within the next three to four years or less anyway (before 5G even fills-in) as the built-in obsolescense kicks in. Your Librem 5 will not experience that same problem. If Purism is still around when 5G becomes a requirement several years from now, a hardware upgrade will probably be available then.


The risk is … that an old version of the software falls out of support, and then later on a serious longstanding security issue is discovered, and it gets patched in e.g. MS Office 2021 but not patched in e.g. MS Office 2016. That leaves you vulnerable even though you have no missing functionality, and you will not be badgered to apply any patch. Maybe no one even bothers to test whether the older version is vulnerable even though in fact it is.

Do you care? Maybe not - but if it’s a company laptop, maybe your employer does care.



Today, I was informed by ChiefGyk3D (Mastodon / Twitch) about Efani, a US-based security-focused mobile service that claims to protect against SIM-swap attacks.

Why Purism Librem 5 Is The Ideal Phone Choice in Terms of Security” - Haseeb Awan, Efani

ChiefGyk3D said at 3:14:00 in today’s stream that Efani uses an AT&T or Verizon (which is known to not support Librem 5) backhaul network.

Assuming this all works on the Librem 5, you should have the option of either T-Mobile and AT&T networks.

1 Like

2024-04-15 – EFANI – Top 10 Most Secure Mobile Phones to Buy in 2024

#1 = Purism Librem 5