eSIM latency and local breakout, explained
Two travellers standing under the same tower in Bangkok can have completely different connections. What separates them is where their data leaves the country for the internet. Pick a destination below and watch the milliseconds move.
- 200,000 km/s
- How fast data moves through fibre — about two thirds the speed of light.
- +10 ms
- Added by every 1,000 km of detour, because the answer has to come back too.
- 20,000 km
- The furthest any two points on Earth can be, which caps the damage at around 200 ms.
Latency lab
Where are you travelling?
Added latency
Traffic breaks out inside United States of America and never leaves the country to reach the internet. There is no detour to pay for.
This is the route our United States of America plans actually use.
Break out somewhere else
What this feels like
- MessagingFeels instant
- StreamingFeels instant
- Maps & browsingFeels instant
- Video callsFeels instant
- Online gamingFeels instant
Distances are measured between country centres, so every figure is an estimate of the detour rather than a speed test. Real-world latency also includes the mobile network you are connected to and the distance to the server you are talking to.
Going to United States of America?
Get an eSIM that works the moment you land, with the breakout shown on the plan page before you pay.
From $2.25
Get a United States of America eSIMBandwidth is how much arrives. Latency is how long you wait for it to start.
A travel eSIM roams onto a local mobile network, so the radio part of the journey is the one locals get. What differs is the next step: where the traffic is handed over to the public internet. That handover is the breakout, and it does not have to happen in the country you are standing in.
When the breakout is far away, every single request — tapping a link, loading a map tile, saying hello on a call — travels there and back before anything happens. Your download speed does not change. The pause before it starts does, and that pause is what people mean when they say an eSIM feels slow.
Your data reaches the internet without leaving the country
- Your phone
- Local tower
- Exit point
- The site
The eSIM roams onto a local network and the traffic is handed to the internet right there. That is exactly what a local SIM does, and it is as short as a route can be — nothing is added, because nothing is detoured.
Your data flies to another country before it reaches the internet
- Your phone
- Local tower
- Exit point
- The site
Same local tower, but the traffic is carried back to the provider's own exit point first — often a continent away — and then all the way back to you. Downloads still arrive at full speed. It is the wait before each one that grows.
What each detour actually costs you
Added latency, in the only unit that matters: whether you notice. Every rung is anchored to a route that really exists, measured from the same coordinates our destination pages use.
0 ms
In-country
The breakout sits inside your destination. Nothing is added at all — this is the route a local SIM takes.
0 msJapan, in-country
1–14 ms
Feels local
A neighbouring country. You would need a stopwatch to tell this apart from a local connection.
5 msAustria → Germany
15–49 ms
Barely noticeable
Same region, one hop over. Calls and streaming are unaffected; only competitive gaming starts to feel it.
16 msThailand → Singapore
50–119 ms
Noticeable
A different continent. Pages take a beat longer to start, and video calls develop that half-second of talking over each other.
99 msSouth Africa → United Kingdom
120 ms+
The long way round
The far side of the planet. Everything still works, but nothing feels immediate and live conversation gets tiring.
152 msAustralia → United Kingdom
So why would anyone route your data across the world?
It is rarely incompetence. Remote breakout is a deliberate trade, and it is usually the cheaper side of one.
One exit is cheaper than a hundred
Breaking out in a country means an agreement, hardware and a minimum spend in that country. Buying it once in Hong Kong or London and pointing a hundred countries at it costs a fraction of doing it properly in each one.
One profile, everywhere
A single global eSIM profile that works in 190 countries is easy to sell and easy to support. The price of that simplicity is that everybody's traffic goes home to the same place, however far away home is.
The roaming deal decides
Providers buy wholesale access through whichever partner covers a region, and the breakout comes attached to that deal. Sometimes the cheapest coverage in a country simply has its exit somewhere else.
How we handle it
We cannot rewrite the internet, and we will not pretend a long route is a short one. What we can do is measure it, publish it, and take the shorter route when the price is close.
Browse destinationsMeasured, not claimed
Every latency figure on this site is the same calculation: great-circle distance to the breakout country, there and back, through fibre. No marketing multiplier.
Printed on every destination page
Each destination shows the exact breakout country its plans use and the latency that implies — including when the answer is unflattering to us.
Shorter routes win ties
When two wholesale plans cover a country at a similar price, we take the one that breaks out closer. When the far one is dramatically cheaper we still list it, and tell you what you are trading.
Latency questions, answered
The things worth knowing before you judge an eSIM by its speed test.
Now go and check your destination
Every country page shows the real breakout, the real networks and the latency to expect — before you buy anything.