Ask HN: What's Your Experience with eSIMs?

[zikohh]

As a tech enthusiast, I'm always excited to dive into the latest advancements, but sometimes, new technology comes with its own set of challenges. Unfortunately, these challenges can turn a fun experience into a frustrating ordeal, especially when the surrounding systems aren’t quite as reliable as they should be.

Recently, I decided to upgrade my SIM plan on O2, the UK's largest mobile network operator. At the time, I was using a physical SIM card but was intrigued by the idea of switching to an eSIM. eSIMs offer some great benefits, like the ability to use two numbers on a single-slot phone and the added security of not being physically removable, though the latter wasn’t my main concern.

I was using an Android device when I made the switch, and a few months later, I upgraded to a new Android phone. The O2 app allowed me to install the eSIM on my new device, but I quickly ran into trouble. Despite following the installation steps, my phone had no signal. The dreaded notification 'SIM 2 not provisioned' kept popping up. I tried everything—deleting and reinstalling the eSIM multiple times, leaving it overnight in hopes it would activate, and even turning off the old device to avoid conflicts. Nothing worked.

In a last-ditch effort, I deleted the eSIM from my old phone entirely, thinking that might solve the problem. But that only made things worse—now I couldn’t install the eSIM on any device. When I called O2 for help, they informed me that their system still registered my SIM as a physical one. To make matters worse, the system was stuck in a processing state, waiting for the eSIM installation to complete before moving forward. Their advice? Wait for 3-5 days for the process to time out because there was nothing else they could do—not even a visit to the store would help.

So here I am, stuck in a tech limbo, waiting for time to do what technology couldn’t. It’s a stark reminder that while new tech can be exciting, it’s not always smooth sailing.

What's your experience?

[blntechie]

I love the convenience of physical SIMs. Will hate the day when I don't have a choice but to 'upgrade' to eSIMs.

I have a phone with dual physical SIM card slots. I can go to any country in the world, buy a SIM, put it in, and am up and running. eSIM provisioning at airports is barely available in few coubtries.

I broke the display of my phone? Easy, remove the SIM and put it in a spare phone and I can still make and receive calls.

[FanaHOVA]

You can buy eSIMs before you reach your destination fyi. Used them in Europe and India through Airalo after buying them in the US.

[skirmish]

I was banned by Total by Verizon for moving my SIM into a different phone. Does it just work with other carriers?

Happy ending though, I switched to US Mobile with an eSIM and disputed the monthly charge by Total on my credit card since I paid for service not provided.

[Bluestein]

SIMs are one of those things that work so well they shouldn't be touched - which doesn't mean doing away with progress (ie. eSIMs) - it means both should coexist.-

[chedabob]

I won't run my primary as an eSIM as it's just way too much aggro to move it between phones if needed, and you're well and truly stuck if you need to reprovision but don't have a Wifi connection.

We've just switched mobile providers at work, and the eSIMs were a monumental headache. A lot of it was user error, but ultimately it's hard to cock-up taking a physical SIM out and putting a new one in.

As a secondary they're great. I had awful speeds on Lebara in Prague on my main SIM, so grabbed a 3-day one off Nomad just for data.

[rcarmo]

As someone who has worked in the telco industry for over 30 years now, I like eSIMs as a _secondary_ method of using services but avoid them as much as possible for any of my critical numbers — simply because I want to be able to move my SIM to another phone in an emergency without needing to visit a store.

In an age where phone authentication is still absolutely critical (banking and all sorts of online services still rely on texting you six-digit codes instead of relying on TOTP air stronger non-phone-number-dependent methods), being without my phone number for a day or more when I’m stuck in the middle of nowhere is completely untenable.

Also, eSIM implementations range from ultra-smooth to hilariously bad. There are still providers (I’m looking at you, Vodafone Portugal) that absolutely require you to buy, unwrap and scan a physical piece of paper with a QR code printed on it, like an animal, _because they actually keep inventory_ of those printed pieces of paper.

Yes, it’s as if the Industrial Revolution was still getting started at telcos.

Anyway, the above is why I will always get devices with physical SIM slots for as long as I possibly can—-and when I can’t, I will likely incur the expense of getting a secondary phone where I can reactivate my critical numbers myself without visiting a store.

They’re great for IoT devices and Internet access, but a liability if you still require receiving texts at a given number for anything important as if your phone dies, you’re SOL—-and nobody in the industry cares about that, or about ensuring travelers can re-activate eSIMs in foreign countries where their provider simply doesn’t exist.

[zikohh]

Yeah, I learnt this the hard way.

[systemtest]

Works great on iOS but can be a bit fidgety. I bought a data-only eSIM for Switzerland and as I crossed the French/Swiss border I had to go deep into the settings menu to enable the eSIM, set it as the data primary and keep using my primary SIM for phone calls and FaceTime, but then also disable data roaming on my primary SIM as to not accidentally occur charges in case reception of the eSIM fails. And disable roaming on the eSIM so I wouldn't occur extra cost if it connected to the French network, as I was close to the border. When going back to France I would disable the eSIM, set the data primary back on my primary SIM and enable data roaming on that SIM (after waiting for it to connect to the French network).

It would be nice if there was a more hands-off approach when crossing a border, or some sort of "do whatever is going to cost me the least amount of money" approach to roaming and having two SIMs.

[acl777]

I used eSIM for traveling - it's been such a joy to have a full working data plan in another country the moment I touch down in the country.

https://redgreenrepeat.com/2024/05/12/traveling-and-your-int...

From your post and experience - I can see eSIM would be a rough experience - my main line at home is still a SIM and the eSIM is optional

[spike021]

I've tried travel eSIMs (Ubigi) on a couple of trips to Japan. In my experience compared to when I've gone and used physical SIMs, the reception and coverage wasn't nearly as good. Just super random neighborhoods and areas where the phone just completely drops connections. Even the top of a mountain near Fuji, my eSIM failed completely but my Japanese friends with eSIMs had completely normal and fast service despite supposedly being connected to the same network (DoCoMo iirc at the time).

Not sure if it's an eSIM issue or that the service (Ubigi in this case) that fronts the cellular network just can't operate it smoothly or what.

[bmoxb]

I can say for certain of course, but I would guess at that being the result of the poor service that travel network providers typically offer. I have also used travel eSIMs in Japan and had generally a pretty poor experience (bad coverage and slow speeds). Conversely, I've had non-travel, regular monthly eSIM contracts in both the UK and Germany and experienced few issues (at least no more than my experience with physical SIM cards).

[weikju]

> Not sure if it's an eSIM issue or that the service (Ubigi in this case) that fronts the cellular network just can't operate it smoothly or what.

Or the bands supported by your phone. Could be any of these possibilities

[totoglazer]

Found it to be a really unpleasant experience using Airalo in Europe on an iPhone. Maybe user error, but everyone in our group had confusing issues. Lots of problems with the phone forgetting the home number meant it was hard to get messages with iMessage, and no SMS caused a big mess with local businesses and with 2 factor/fraud detection. No phone number was also an issue a few times. I don’t know what we did wrong, but it was really frustrating.

[OutOfHere]

This is on you for relying on SMS. Switch to a proper 2FA app or at least to Google Voice.

[bloggie]

I use eSIMs exclusively for travelling. They are extremely convenient and the cost is great. The alternative is often handing over your passport to a random shop seller that then does who-knows-what with it before handing over an expensive and easily-lost SIM that usually costs a lot more and only works in one country, and may not be rechargeable.

I tried a few different services before settling on Airalo, which I now use exclusively. Nomad did not work at all. Some others like 3HK or DENT were cheap but unreliable.

Also, using Airalo in China gets you around the great firewall.

Oh, I also use Keepgo for cheap 365-day LTE access on an iPad. It has been reliable.

Although my experience has been good with iPhones, it has not been good with Android phones. This may be related to your experience, or your poor experience may be due to a shaky rollout from a legacy carrier.

For my main phone I will still prefer a normal SIM as the service can be easily transferred if the phone is damaged. Maybe this perception will change as eSIM client-facing features improve.

[minkles]

This is the fateful combination of O2 and Android together, possibly the worst experience in the universe (from experience). Nothing but trouble for years.

I dumped my Pixel 6A and O2 a couple of years back after a roaming shit show in Iceland where they billed me £400 and went iOS and Giffgaff. Despite giffgaff being the same company in theory keeping a physical sim with them has been trouble free. And I just add an additional eSIM when travelling wherever and everything just works! Giffgaff gives you 5Gb of roaming a month as well in Europe which is good enough for the odd weekend here and there if you are careful and enable low data mode.

[warkdarrior]

I got a prepaid eSIM from O2 this summer and then traveled through Europe. It worked great, got some 50GB of traffic for a month, had no connectivity issues.

[solardev]

Been using them on Google Fi with a Pixel for several years. Works great.

Recently traveled to an area with no reception and gave US Mobile (a three-carrier MVNO) a try on the second sim slot. They issued me a AT&T esim first, which worked but was slow. I switched to T-mobile and they reissued me a new esim, which started working in a few minutes. Then I canceled service altogether and went back to Fi (I prefer Google) since the performance was the same.

But the whole experience only took a few minutes and didn't require me to go to any store to pick up a sim. That was really nice, especially when testing out different carriers in place.

[ivanjermakov]

eSIM is amazing for purchasing roaming internet while traveling. There is a eSIM aggregator that I can recommend: https://esimdb.com/

[minkles]

Urgh some of those are crazy expensive. Best to pick by destination if you can.

For example they charge you $23 for 10 gig in Central Asia there but if you get a local eSIM it’s $5 for the same and $10 for unlimited. I just WiFi hopped because there was bugger all reception out there anyway.

[bloggie]

they also work as soon as you get off the plane! so you don't have to waste time buying an overpriced SIM at the airport while jet-lagged in a foreign language at a kiosk that may be closed.

[oriettaxx]

exacly!!! super reccomended

[lxn]

I've been using eSIMs for a few years, and my experience is similar to yours. I'm an expat living abroad, and I want to keep my old phone number (from my home country) and my new phone number (from the country I currently live in).

After two days, my first phone with an eSIM died, so I had to go to a telecommunication provider's physical store to install a new eSIM on the replacement phone.

Now, I try to keep my main SIM physical and the secondary (less important) one as an eSIM. In my case, my native country's phone number is now an eSIM.

You can ask your provider for a blank physical SIM, and in case you lose your eSIM, you can usually call them, go through the identification process, and they can move your number back to the physical SIM you have as a backup based on the serial number on the SIM. I do have blank physical SIMs for my eSIM. I never had to use them, but my girlfriend did (she's using the same setup). Once you're back to physical SIM, you can usually change to eSIM via the app. Be aware that some companies charge this switch between SIM and eSIM.

Having the secondary number as an eSIM makes it easier to use virtual SIM providers like Airolo when travelling since I don't have an issue disconnecting that number for the duration of the holidays.

If you have just one number, I'll suggest to keep it as a physical SIM.

[hadeszero]

I purchased the iPhone 14 right when it was released. In the US it seemed like some of the carriers were not prepared yet still offered the phone for purchase.

There was this issue where I wouldn't receive any texts or voicemails due to the number being ported over to eSIM. The worst thing is that nobody who worked for the carrier had any clue either, there was zero acknowledgement that there was an issue going around.

I had to spend a day reading through the forum posts, which there were a bunch, and someone wrote about their experience and suggested to talk to the tech but mention specific things something like "reauthorize the device", and finally got it to work. Similar issue happened to a friend on a different carrier but their employees actually knew about the issue and solved it with a single trip to the store.

I wouldn't really blame this issue on the technology but just incompetence from the carrier made the eSIM transition a nightmare, I really don't get why they bothered to offer the iPhones in the first place if their tech is still playing catch up.

[wryoak]

What a ride

Personally, I used them with great success traveling RTW. Being able to still use my home number (on rare occasions) while having a cheap local eSIM was great. Usually just for data (navigating) but sometimes having a local number was also useful. The apps generally sell overpriced eSIMs, unsurprisingly, but are very convenient. Don’t really have a reason for two sims in my home country though.

iPhone 15 fwiw

[ScannerSparkly]

Personally, I use physical card for my main SIM. However, when I travel I prefer using eSIMs as it is so much easier rather than searching for one when you arrive in a new country. I definitely had some set up problems regarding travel eSIMS in the past. With some very known providers that I tried I always had some troubles like QR codes not working correctly or not getting service even though it showed that everything is good to go.The support would not always be very helpful and that would take me at least a few hours to get everything set up and ready to use. Until I found out about one brand called Saily that actually have an eSIM card that you have to install only once and use for all future travels. That actually was a life saver because now all I have to do is buy a plan in their app and activate it every time I travel. I only had to set up eSIM once and honestly did not have any problems there like with others. Maybe it was the easy setup or clear instructions.

[runxel]

Can't say that I've had a bad experience. Love eSIMs!

In my iPhone I have one physical SIM for my private number and an eSIM for my business number. Works great. When traveling I disable the business number and instead use Airalo.

So far it's much more pleasant than a "real" SIM, especially when traveling. No hassle of getting a card etc.

[zikohh]

Two years later, I've experienced the same issue as someone else https://community.o2.co.uk/t5/Apple/Urgent-Help-Needed-iPhon...

[wtmt]

In India, I’ve been using eSIM for a few years now (on iPhone, not Android). It’s been working quite well. Transferring eSIM from one iPhone to another works fine. Activation of an eSIM takes a few hours, at the most. Due to regulations, there are restrictions placed on sending and receiving SMSes for the first two days.

The only hindrance I’ve seen is that to get an eSIM in the first place, an SMS has to be sent from the phone even though the eSIM activation QR code is sent over email (and the registration of an email address is also possible online). In some cases, like switching from one type of plan to another (postpaid to prepaid), this would require getting a physical SIM card (that’s the default for any connection), using it from a phone that has a physical SIM slot and then using that for the SMS.

[jedberg]

It's been great for me. I just went to Europe and used an eSIM with a different plan while I was there. The biggest issue is that it required some unique settings deep in the iPhone config, but once those were properly set it all worked great.

Also it was kinda cool having two lines for a day before I left.

[mattl]

I’ve had my iPhone on eSIM (T-Mobile and Verizon) for the last 3-4 years with no issues.

Sorry to hear you’re having issues.

[miohtama]

I am using https://www.dent-app.com/ for travelling and never going back.

I would also use eSIM for the main SIM, but the local monopolist telecom do not give this option yet.

[zikohh]

Dent looks really cool thanks for sharing!

[Yizahi]

My experience - I've bought a two sim phone this year to use two different physical sim cards. :) Experience of my colleague - he couldn't transfer his esim from old iphone to a new one, due to the unrelated but still unresolved govt. issue. Basically the phone was linked to a certain service, that service has expired/blocked due to inactivity, and without working service esim can't be moved. It's not esim tech fault obviously but if it was a physical sim the issue would be solved in a minute, regardless of the external issues.

[crispyambulance]

I tried eSIM’s for the first time while traveling in Ireland, used Orange on iPhones.

Terrible experience. So confusing. Data worked fine but I had a lot of trouble with everything else. Probably should have taken more time to do it, I researched and bought them on the ride to the airport and then activated upon arrival, jet-lagged and tired.

It’s just too much to go through. And it seemed to take arbitrary amounts of time for configuration changes to work, with no feedback on if what you’re doing is correct or not.

The physical sim days were easier. Oh well I will try again on the next international trip.

[gtvwill]

I needed dual sim so I could separate work from private. Ordered a Canadian Samsung s20 because their dirt cheap that had 2g support. Reflashed it with American firmware and now I have no 2g/3g support but do have dual sim (turns out same hardware in the devices they just use rom to change featutes based on where in the world you are as the base chip it worked on supported all of them).

I use the esim for work. Works great transferred a real sim to it via online portal, cost me $120aud for whole year plan, unlimited calls and text.

[attendant3446]

I like the idea of eSIM, but the reality is different. I think it all depends on the country that issues the SIM card and/or the telecom. For example, right now I'm using a SIM card from a telecom that provides eSIM with their app and has very limited support for phones (it's basically only iPhone and Samsung). Even though the phone supports eSIM, I can't use it due to some artificial limitation. But I can use the old and trusted physical SIM card. So I'd stick with it.

[aristus]

A SIM card is an often-overlooked "what you have" second factor, yes leaving aside phone company social engineering hacks.

I made the mistake of buying an iphone on a trip to US, which is eSIM only. The tech works fine --Google Fi is a pretty good example-- but I later traded that phone for the exact same "international" model, traded even plus cash, to get my slot back.

[biztos]

Using Airalo plus a Verizon physical sim in Europe with an iPhone SE 2 worked, and I found the cost fair enough, but it drained my battery like mad, so bad in fact that I found myself turning the eSIM off a lot. I think this is probably just Yet More Shoddy Apple Software, and I will probably use eSIM in future, but it’s something to watch out for.

[rootusrootus]

I can't imagine how SIM vs eSIM would make any difference, I would ascribe battery drain to something else tangentially related, like using a mobile network with weak coverage that has the phone constantly ramping up power to find a decent signal.

Anecdotally, I've used three eSIMs in my iPhone 15 (only two are allowed to be active at the same time, though), and my wife has a physical SIM and an eSIM on her older iPhone, and we've not experienced any weird behavior.

[oriettaxx]

super great as secondary sim (I mean internet)

I experienced some, but to me https://etravelsim.com/ is good choice (europe and balcans)

support impressive (super responsive) plus you get a uk number, free calls to other their esim... just discovered this e-sim world thanks to HN: it is the future

[nirav72]

etravelsim is where I got a 4gb esim for traveling in a few Mediterranean countries recently. Worked great and was cheap. Only issue I had was apps that were dependent on a phone # like WhatsApp acted a bit weird. But other than that everything else worked just fine.

[kioleanu]

I had to get an eSIM for my watch - it's also from O2, but in Germany. It's basically a copy of the physical SIM I have in my phone and it worked perfectly. My only bother is that they charge me 15 euros activation fee everytime I reset my watch. I can't set it on the watch without activating it, even if it's activated

[ChrisMarshallNY]

I have two lines on my iPhone. One is an eSIM (AT&T), and the other is a simSIM (T-Mobile).

I don't travel internationally, these days, so I know that I'm not a "power user," but my experience has been great.

Does what it says on the tin.

From what I hear, Apple is considering going all eSIM, on future phones. There may be nations, where that won't wash, though.

[rootusrootus]

> Apple is considering going all eSIM, on future phones

Already there. My iPhone 15PM does not have a SIM slot, and I think that is true for the entire iPhone 15 lineup.

[reboot81]

Had it for years. The security, convenience and not having to wait 2-3 days for a replacement is great. At work they haven’t supplied users who select an iPhone with physical SIM the last two or so years. Even my mom had her new phone set up with an eSIM. Never heard of any issues, and our department has 100s’s of devices with eSIM.

[trelliscoded]

I use a Helium Mobile eSIM, which I pay with crypto. I set it up in something like 10 minutes when I became eligible for an account. No problems so far.

I've also had eSIMs from FirstNet and AT&T, no problems there either. Running dual-sim hasn't been a problem either on any of my Galaxy or iPhones.

[fy20]

On a related note, does anyone know of companies that let you sell esim services whitelabelled? I've noticed a ton of new esim travel apps appear this year, and I'm guessing they are just marketing and using a third-party for the heavy lifting.

[OptionOfT]

Mint charges for eSIM provisioning when changing > 2 times per year.

Also, ensure that you have a backup plan to reset your password.

For example, to reset your password on Mint, they send you a text. What happens when you don't have a SIM? You're stuck.

[stevenwliao]

Airalo works well on my iPhone for travel. I had super fast data in Europe (including UK), Japan, Mexico.

IIRC the rates are not competitive compared to local plans though, so not sure if it's worth it for you.

[sam29681749]

I bought a temporary esim in Japan that I couldn't get working. Buying a physical sim to replace it was a mentally cheaper option than continuing to troubleshoot it.

[Lammy]

I've never used one but am biased against them because they seem like a step toward a future where it's impossible to unplug a device from The System at all.

[ljsocal]

I’ve had all good experiences with eSIMs. For service outside the U.S., HolaFly works well, is reasonably priced and is easily accessed for support, if required.

[BWStearns]

I used one on my iphone for a work trip and now my iMessage stuff is all broken after switching back. There's still some rough edges.

[rootusrootus]

That's not specific to eSIMs, that is an iMessage issue. Having done this recently myself (just got home yesterday from a trip to the UK), my recommendation for anyone about to travel with an iPhone is to get a data-only eSIM that works in your destination country, then toggle off roaming on your primary line and make sure WiFi calling is enabled. If the phone asks to add a new number to your iMessage, refuse. Then your phone just works like normal, including iMessage, but without the roaming charges.

Oh, and if my experience is typical, don't go with O2 in the UK. I was disappointed in both the coverage and the performance. Even in London proper it was frequently crappy.

[kingkongjaffa]

I’ve used the app Nomad on iphone a bunch of times to buy an esim for roaming mobile data on holiday.

My latest sim from O2 in the Uk is an eSim.

[UniverseHacker]

This is not an eSIM problem, but a problem with your cell phone carrier database systems. Clearly you are still registered as using the eSIM and unless you can get a support person to fix it (unlikely) you are screwed. I had the same issue with Visible wireless here in the USA, and the only way to fix it was to create an entirely new account and plan, under a new e-mail address, and port my phone number over to that.

Overall, eSIMs work great... I have a big problem with companies refusing to mail SIMs nowadays without signature confirmation and weekday only delivery - which means people that have jobs cannot obtain cell phones. Total craziness... I am so glad for eSIMs, because I don't get stuck in 'redelivery attempt scheduled for tomorrow' hell.

[floam]

One nice thing about eSIM is if someone steals my iPhone, they can’t remove the SIM card and keep the device offline.

[nixosbestos]

eSIMs are fantastic! Except that they just make me even more irate with various service providers that don't work with them, or don't work with the VOIP number that I use when using data-only SIMs.

Seriously, my Airbnb account has been broken for TWO MONTHS because Airbnb:

1. Uses SMS (only) for 2FA. For a fucking international travel company.

2. They don't support VOIP numbers for SMS 2FA. An issue I reported to them at least 4 times over the past 2 years.

I'm sorry, but what the fuck is wrong with people. Not everyone uses an iPhone, and even then, I'm pretty sure those iPhone carriers will NOT DELIVER SMS WHEN IM IN THE MIDDLE OF NOWHERE.

If I could donate 10% of my salary to just sending boxes of dog shit to the AirBnb C-Suite, I would.

[OutOfHere]

In between this and hidden cameras, I am better off not using Airbnb.

[croemer]

Totally smooth experience on my Pixel 8, both in home country (for dual sim) and when travelling.

[x0x0]

same on a pixel 7. Super smooth experience with a mexican and multiple US mvnos.

[devinegan]

Love my Tello esim, like $5/mo for a line that receives real text messages.

[kkfx]

I'll do my best to avoid using them, so far successfully...

[alphabettsy]

No issues for me other than sometimes being slow to provision.

[ochronus]

Pretty uneventful. It just works.

[wkat4242]

No experience. They're still not supported on prepaid lines and I don't do contracts. So that's it for me.