SIM for GPS tracker

Can anyone suggest a reasonably priced SIM for use in a car GPS tracker?

I've been using a SIM from RWG Mobile on the NOW/EE network for several years. It started at a very reasonable £1/month for 500MB of data and then, a year or so ago, doubled in price to a still reasonable £2/month. About 3 weeks ago, it stopped working and RWG's support doesn't respond, so it looks like it's time to part ways.

I'm only paying £6/month for my main mobile with 8GB of data so don't really want to pay something comparable for a very-low use SIM in the tracker. 500MB is ample but it needs to receive SMS (I'm unsure if all data-only SIMs do this). Any suggestions?

In reply to a post by ashdown:

Can anyone suggest a reasonably priced SIM for use in a car GPS tracker?

I've been using a SIM from RWG Mobile on the NOW/EE network for several years. It started at a very reasonable £1/month for 500MB of data and then, a year or so ago, doubled in price to a still reasonable £2/month. About 3 weeks ago, it stopped working and RWG's support doesn't respond, so it looks like it's time to part ways.

I'm only paying £6/month for my main mobile with 8GB of data so don't really want to pay something comparable for a very-low use SIM in the tracker. 500MB is ample but it needs to receive SMS (I'm unsure if all data-only SIMs do this). Any suggestions?

This won't work for your SMS requirement ("EXCLUSIVE UK DATA-ONLY - This Sim card does not support calls, texts, or roaming.") but sharing in case you find an alternative tracker that uses data rather than SMS.

I used to have one from Three from Amazon which was 24 month validity. They have one to 8th Feb 2027 and 25GB (not per month but during almot two years) for £65.. you can get a £24.99 for 3GB to April 2026 too (second option on that page.. I don't know how much data you need for tracker.

See https://www.amazon.co.uk/dp/B0CX1VZH2S for an example but note I don't know the seller so not a vouch on that side.

seb

It obviously depends on exactly what traffic there is between you and your tracker. I have a simple GPS tracker that responds to phone calls and texts by sending one text that will contain varying data depending on the content of the text it receives. No other input or output. For this I find a PAYG SIM on the TESCO LITE tariff is perfect. 4p per text with no other costs.

In reply to a post by cjn:

It obviously depends on exactly what traffic there is between you and your tracker. I have a simple GPS tracker that responds to phone calls and texts by sending one text that will contain varying data depending on the content of the text it receives. No other input or output. For this I find a PAYG SIM on the TESCO LITE tariff is perfect. 4p per text with no other costs.

I was thinking something similar, but 1p mobile.

Yes they're well-priced for general use, but you have to top-up £10 every 60 days, which may be a bit wasteful if all you're doing is sending 1p texts. I haven't been able to find anything better than Tesco Lite for just occasional texts. To keep your account open you only need to send 1 text every 180 days - 8p/year.

If you can easily change the SIM / number every 6-9 months get a Lebara (uses Vodafone network) offer sim and when the offer price ends just cancel and buy another Lebara offer SIM on a different number? You probably do not need to but I would use a different email address each time.

Usually they are around £1/month for several months with unlimited calls/text and a decent amount of data usually 5GB-50GB/month.

hotukdeals.com and search for Lebara for the current offers - they generally point to MoneySavingExpert.com if you want to sign up without hotukdeals affiliation links.

Thanks for all the suggestions - much appreciated.

My tracker sends its position every few minutes to a nominated IP address, hence the need for data. I use the excellent (open source / free) Traccar software on a cheap VPS and this provides nice maps showing where the car has been. It uses inbound SMS to set the IP address, etc, hence the need for at least inbound SMS. I think some data-only SIMs don't have a phone number and therefore can't be sent SMS.

The tracker can also be programmed to respond by SMS to an SMS request for its current location and the Tesco Lite SIM sounds ideal if that were the only requirement but I do like the continuous reporting and the historical maps so I need a data SIM if possible. I've used 1p Mobile in the past but the need for regular top-ups became expensive and it was wasteful to have an ever-increasing balance that wasn't being used.

The prepaid data-only Three SIM sounds interesting but I'm not sure if I can program the device if it won't accept even inbound SMS. Lebara looks a good possibility if I can avoid feeling guilty about exploiting their offer!

I am suprised that no-one seems to offer a SIM specifically for use in trackers with a very low data and SMS cap. There's an opportunity there for an enterprising supplier.

In reply to a post by ashdown:

I am suprised that no-one seems to offer a SIM specifically for use in trackers with a very low data and SMS cap. There's an opportunity there for an enterprising supplier.

Vodafone used to sell a pet tracker clip ("Curve") which came with its own service at £1.50/month for the first 2 years, then £3/month.

They have exited this market, and terminated the service, so I have a useless tracker now.

Clearly at the £3 price point, there's not enough money to be made from such a low-revenue product.

£10 every 60 days with 1p mobile makes no sense; you might as well use the standard Lebara £5/month monthly renewing service, which gives you 5GB, 1000 texts, 1000 national minutes and 100 international minutes.

AAISP have a data-only SIM at £2.00 per month plus 1.75p per MB. But I don't know if it does SMS - presumably not. And your usage would have to be less than 170MB per month to be worth it.

I've had a look at the Tesco Lite PAYG tariff and see that it also offers data at 10p/MB without regular top-ups. That may be a little misleading as I've found in the past that charging for data can be on a "per connection" basis, so for example sending a few bytes followed by no more before the connection times out may be charged as if it were a full MB. That sort of charging could be expensive for a tracker that sends a hundred bytes every 5 minutes. Alternatively, if it charges 10p/day if the total data sent in a day is less than a MB, it would be fairly good value. It may be worth getting one and experimenting.

Hadn't noticed that 1p have changed their t&c's since I last looked for a minimum spend SIM, IIRC you had to top up £10 every 6 months, looks like those sorts of deals have been dropped by most.

Please would you tell us what GPS tracker you have.

If you search online for M2M SIMs, you'll likely find some options.

I use a all-network roaming SIM in a tracker, costs around 8p per Mb / per text. Has a UK number. It's only 49p per month for mine but that deal isn't available now, it's now 8p per day rental (with 8p data/text/calls).

I've used Giffgaff before on a tracker too, without a monthly plan their 10p/MB worked out nicely, they didn't round up the tiny amounts of data usage. Their site makes it unclear if it's possible these days to have a SIM without a monthly plan on it.

In reply to a post by Michael_Chare:

Please would you tell us what GPS tracker you have.

Mine is a generic no-name tracker bought from eBay some years ago. This particular model is no longer available but there are plenty listed on eBay. Many of them encourage an ongoing subscription but it's usually possible with a little reverse engineering to identify the particular protocol being used and set it up to work with a system like Traccar.

I've obtained a Tesco SIM to experiment with and put it on the PAYG Lite tariff which ostensibly charges 10p per MB but Ive found it's not suitable for use in a GPS tracker because of the way it (mis-) charges for data.

I've measured the data used by my tracker by monitoring the server (using tcpdump if anyone's interested). It uses 85 bytes of data on each position report and sends reports every 3 mins when static and every 30 seconds when moving. In the worst case, if it were to move continuously for 24 hours, it would use 245 KB in a day. So the maximum usage in a month is 7.3 MB.

If a mobile provider genuinely charges 10p per MB, that would be a maximum of 70p per month.

I activated the Tesco SIM this morning and it's used just over a pound's worth of the initial £5 top-up in around 4 hours. I'm pretty sure that what's happening is that every time the TCP connection drops, Tesco's algorithm rounds up the data used in that connection to a MB. So, less than 100 KB has been charged as if it were more than 10 MB.

I suspect other Telcos do the same but this is the first time I've gathered hard evidence. The advertised price per MB is misleading, at best. Anyway, this rules out Tesco Lite as a contender.

I don't doubt your findings, but running tcpdump on the client side as well if possible and comparing the two might also be helpful - if the thing is retrying ten times before the server responds due to problems between Tesco and your server then you won't see that data but Tesco will be charging for it. It's not going to account for the differences here though, and there's no mention of rounding for data charges in the T&Cs for the PAYG tariff.

It might be worth asking about these plans https://www.thingsmobile.com/business/plans/pay-per-...

Edited by jpm (Mon 17-Mar-25 16:45:35)

In reply to a post by jpm:

running tcpdump on the client side as well if possible and comparing the two might also be helpful - if the thing is retrying ten times before the server responds due to problems between Tesco and your server then you won't see that data

I take your point but the tracker is a black box with a SIM slot and no way of talking to it directly. The only way of measuring its cellular data output is by a man-in-the-middle attack and I don't have the equipment to do that.

I'll do a more controlled experiment by ejecting the SIM for a day to ensure that charging has settled, then put it back for several hours while capturing all the traffic at the server, including any TCP disconnections. If that shows discrepancies in the charging, it may be worth raising the matter with Tesco.

Unforunately, Tesco Mobile doesn't provide any granularity in reporting data use. All I can see is the credit balance decreasing over time.

In reply to a post by jpm:

It might be worth asking about these plans https://www.thingsmobile.com/business/plans/pay-per-...

Thanks for the pointer. If I understand correctly, that would cost just over 2 Euro per month for 7 MB of data.

1p Mobile offer sims for IOT devices and trackers :

https://www.1pmobile.com/not-just-phones

They also offer "Boosts" on their prepaid service , I use the Unlimited 12 month boost @ £48/year:

https://www.1pmobile.com/siminfo?prodid=SBCT500

Thanks. I wasn't aware of 1p Mobile's IOT offer and ther itemised data use is particularly attractive.

£4 per month isn't too bad but I'm still hoping for a service around £2/month. I know that £4/month is a fairly trivial cost in the grand scheme of things but it just seems a waste to pay for umpteen minutes and texts when I need none of them and for a substantial amount of data when I just need less than 10 MB/month. It does show, though, how cheap mobile connectivity has become.

I do appreciate all the suggestions made in this thread. It should give plenty of ideas to anyone else looking for something similar.

try msc's lebara deal; 35gb @75pm for 9 months

Yes, that was suggested earlier in the thread. I'm certainly tempted to give a breathing space while looking around further. I'm not sure it's entirely ethical to take advantage of this offer without the intention to continue after 9 months but, on the other hand, my measly 7 MB/month won't actually cost them much.

I mentioned a couple of days ago that Tesco Mobile appears to round up very small amounts of data and effectively charge more than their advertised rate. That conclusion may be flawed as it assumed that the PAYG credit balance displayed in their app was correct. It isn't!

After an initial top-up two days ago of £5, last night the app showed my credit balance as £3.97. This morning, with no usage and no top-ups, it shows my balance as £4.96. This also happened two days ago but I thought I must have mis-read what it was telling me. This time I have screenshots one and two to prove it. This is weird behaviour and I've no idea what Tesco is actually charging for data.

In reply to a post by ashdown:

Thanks. I wasn't aware of 1p Mobile's IOT offer and ther itemised data use is particularly attractive.

£4 per month isn't too bad but I'm still hoping for a service around £2/month. I know that £4/month is a fairly trivial cost in the grand scheme of things but it just seems a waste to pay for umpteen minutes and texts when I need none of them and for a substantial amount of data when I just need less than 10 MB/month. It does show, though, how cheap mobile connectivity has become.

I do appreciate all the suggestions made in this thread. It should give plenty of ideas to anyone else looking for something similar.

The thing is the free stuff to include isn't because they expect everyone to use it. Just like at work I sell servers with unmetered bandwidth - not because I hope everyone used 1Gbps solid (it would cost more than server usually if so) but because I don't want the hassle of metering it.. and some people want one thing some another so a bundle means they can justify the package overall

For the mobile data you could use AAISP (£2/month+VAT) but data on top.. but it's data.. you can terminate it on L2TP so you could do MiTM on your side too.. and they are the sort of people who I would expect to handle billing ok.. but no SMS I believe - data only usually means that for IoT.. not SMS too
https://www.aa.net.uk/voice-and-mobile/data-sims/

seb

Edited by seb (Wed 19-Mar-25 22:33:22)