A tracker works abroad when it can get a GPS fix and its SIM can roam onto a local network. GPS is global, but transmission depends on roaming agreements. Thatcham Research certification sets the standard insurers trust, yet network technology, data use and plan limits still decide what you see on your screen.
TL;DR:
- S5 certification requires a roaming SIM, while S7 certification only requires a transmission method, so confirm roaming support for the exact S7 model.
- Before departure, get written confirmation of destination networks and test roaming in the UK; older 2G or 3G units may lose service after network shutdowns.
- Location pings use little data, but remote dashcam video can raise roaming costs; disable live view abroad and watch for accidental border network connections.
- The UK caps participating EEA EFTA wholesale data at €1.30 per gigabyte until January 1, 2027, then €1 per gigabyte; retail charges differ.
Table of Contents
- How does a tracker connect when you leave the UK?
- What do SIM roaming and UK regulation mean for your tracker?
- What do Thatcham S5 and S7 certifications require for roaming?
- What should you check before you travel?
- What commonly goes wrong abroad, and how do you fix it?
- Why do we recommend certified, roaming-capable trackers?
- How do we help you stay covered overseas?
- FAQ
- Sources
How does a tracker connect when you leave the UK?
Separate systems do separate jobs. Satellite positioning (GPS and other GNSS constellations) tells the tracker where it is. It does not send anything anywhere. That second job belongs to the SIM inside the unit, which passes the coordinates to a mobile operator, which relays them to you.
So a tracker can have a perfect satellite fix and still show nothing on your app. If the SIM cannot attach to a local network, the position stays stuck on the device.
- GPS or GNSS reception: works almost anywhere with a clear view of the sky, regardless of country.
- SIM and roaming: the tracker reports only through an operator its SIM is allowed to use in that country.
- Hardwired vehicle trackers (S5 category): draw power from the vehicle, so they keep transmitting as long as the network lets them.
- Battery asset trackers (S7 category): transmit less often to save power, so updates abroad may arrive in longer intervals.
When a tracker goes quiet overseas, the question to ask is not “does it have GPS?” but “which networks can its SIM reach here?”
What do SIM roaming and UK regulation mean for your tracker?
Plainly put, a tracker works abroad only if its SIM has roaming agreements in the destination. Without them, there is no route for the location data to travel.
Roaming costs between operators are shaped by UK law. The UK now sets maximum wholesale roaming rates with participating EEA EFTA states, and the 2026 regulations cap wholesale data at €1.30 per gigabyte until 1 January 2027, falling to €1 per gigabyte after that. The same figures appear in the Roaming Regulations schedule. These are rates between operators, not what you pay at retail, but they influence how providers price tracker SIMs for travel.
Wholesale roaming data is capped at €1.30 per GB until 1 January 2027, then €1 per GB, which keeps the operator cost of a small tracker data stream low.
Ofcom’s guidance on using your mobile abroad points out that roaming can bring extra charges and that 2G and 3G switch-offs can cut off older devices, so checking with your provider before you travel is sensible. That matters for older tracker hardware built around legacy networks.
Data use is the other half of the cost picture:
- Telemetry: location pings are tiny packets, so a standard tracker uses very little data even over a long trip.
- Live video: a dashcam with remote live view moves far more data, and that is where roaming costs can climb.
- Border areas: a SIM can attach to a neighbouring network without you noticing, which is why Ofcom’s roaming guidance asks providers to notify customers and explain how to avoid inadvertent roaming.
What do Thatcham S5 and S7 certifications require for roaming?
Certification is the anchor point for insurance-approved tracking. According to Thatcham’s vehicle security product definitions, certified S5 vehicle tracking systems must include a roaming SIM as part of the insurance-approved standard. S7 asset location systems must offer at least one means of signal transmission, and roaming capability varies by manufacturer and model.
- S5: roaming SIM is part of the certified specification, which supports recovery wherever the vehicle travels.
- S7: transmission is required, but you should confirm the roaming details for the exact model you buy.
- Insurers: Thatcham Research tests and certifies these categories, and insurers rely on that certificate when they set cover and premiums.
For owners taking a vehicle abroad, the certificate and the roaming SIM work together. One satisfies the insurer, the other gives you a realistic chance of tracing a stolen vehicle across a border. Our guide to what a Thatcham certified tracker is explains the S7, S5 and S5 Plus categories in more detail.
What should you check before you travel?
A few minutes of preparation prevents most overseas surprises. Work through these in order:
- Ask your installer or provider to confirm roaming capability and the networks your tracker can reach in your destination, and keep that confirmation in writing or as a support ticket.
- Confirm whether your unit sends simple location data or larger features such as dashcam live view, and switch off the heavy ones abroad if you need to.
- Run the destination through Ofcom’s Map Your Mobile for UK coverage, and take extra care near the Northern Ireland and Republic of Ireland border.
- Check that your tracker supports 4G or 5G, because units limited to 2G or 3G may lose service in some countries.
- Carry your Thatcham certificate, installation paperwork and the tracker’s IMEI in case police or your insurer need them.
- If you travel often, ask about global roaming SIMs or multi-IMSI options.
Pro Tip: Ask for a roaming test while the vehicle is still in the UK, so any fault is fixed before the ferry or flight.
Our checklist for trackers abroad walks through the same steps in a printable format.
What commonly goes wrong abroad, and how do you fix it?
Most failures come down to a few common causes, and each has a simple remedy.
- Network mismatch: an older tracker built for 2G or 3G may find nothing to connect to. Upgrade to a 4G or 5G capable unit, or ask for firmware and network provisioning.
- Roaming not enabled or limited: ask your provider to switch roaming on and verify it, ideally with a test before departure.
- Data-hungry features left running: move to telemetry-only mode or disable live video while abroad.
- Inadvertent roaming at borders: ask about preferred-network locking and provider advice for border regions.
Why do we recommend certified, roaming-capable trackers?
Our view is simple: a Thatcham certificate and a confirmed roaming SIM belong together. The certificate tells your insurer the device meets a recognised standard. The roaming confirmation tells you it can actually report from the road in Spain or the Republic of Ireland. Many owners buy for the first and never ask about the second. At fitting, we supply the certification paperwork insurers expect. If you are planning a trip, contact us before you go.
— Thatcham Trackers
How do we help you stay covered overseas?
We supply Thatcham-certified trackers with nationwide fitting. Choose between the Thatcham S7 at £169, the Thatcham S5 at £349 and the Thatcham S5 Plus at £449, all one-off prices. Not sure which suits you? Our tracker selection page explains the differences.
When you order, ask us for:
- information about roaming SIMs and the networks they use in your destination
- your insurer-ready Thatcham certificate
To book fitting or ask a question, start at Thatchamtrackers.
FAQ
Do GPS trackers work worldwide?
GPS positioning works worldwide, but reporting that position needs a SIM that can roam on a local network. A tracker with no roaming agreement in a country will hold its location without sending it. Check roaming coverage for your destination before you travel.
Is it illegal to put a tracker on a car in the UK?
Fitting a tracker to your own vehicle is normal and is often an insurance requirement. Tracking someone else’s vehicle or person without their knowledge raises legal issues, so seek professional or official guidance for your situation.
What is the best GPS tracker without a subscription in the UK?
Insurer acceptance depends on Thatcham certification, so start from certified devices rather than from subscription terms alone. Our Thatcham S7 is a one-off purchase at £169. Confirm any ongoing connectivity terms with us when you order.
Will my tracker lose signal when I cross the Channel?
It may briefly, while the SIM attaches to a new network, and it can lose service if the hardware only supports 2G or 3G. A tracker that supports newer mobile networks and has confirmed roaming should reconnect without your help.