"Unlimited" is the only word in mobile data that means one thing in the advert and something else in the terms. On the product page it means stop worrying about gigabytes. In the terms it means something far narrower: there is no counter that cuts you off — but there is almost always something that slows you down.
That gap is where the frustration lives. Nobody minds a fair use policy they knew about. People mind on day four, when the map takes thirty seconds to draw and nothing they read before paying said it could.
What the fine print actually says
Here is how one of the larger travel-eSIM brands words it in its own terms. Read it slowly — it's representative of the category, not unusual:
If you purchase an "unlimited" Trip Data Plan, please note that this means there is no fixed data allowance that automatically stops data use, but your data coverage and speed may be subject to a network service provider's fair use policy. This means that in order to ensure a high quality of service for all users, the network service provider reserves its right to impose restrictions or limitations on data usage or speed if your usage is deemed excessive or if it negatively impacts the network performance of other users.
Unpack it and there are three admissions in a row. "No fixed data allowance that automatically stops data use" — that's the actual promise, and it's a real one: you won't be cut off mid-navigation. "Restrictions or limitations on data usage or speed" — the speed can be reduced. "If your usage is deemed excessive" — judged by the local network operator, against a threshold that sentence carefully does not name.
None of that is dishonest. It's just a lot of work being done in small type, underneath a word printed in large type.
Four limits hiding behind one word
A daily high-speed allowance. The most common shape by far. You get full speed up to some volume each day; past it, the connection carries on at a reduced rate, typically resetting on the next daily cycle. The plan never "runs out", so unlimited stays literally true.
The throttled speed itself. This is the number that decides whether throttling is a mild inconvenience or the end of your afternoon. Reduced-but-usable still carries maps and messaging. Reduced to an older network generation means pages that time out.
Hotspot sharing, capped separately. Tethering a laptop is frequently metered even when phone data isn't — a genuinely different allowance from the headline one, and the one that catches remote workers out.
Congestion priority. Independent of any threshold: when a cell is busy, visiting traffic is commonly served after the local operator's own subscribers. Full bars, nothing loading — the same effect we covered in why your phone stops working in a crowd of 100,000.
Why the boring explanation is the true one
Wholesale data costs the reseller money per gigabyte, in every country, always. A plan sold for a few euros a day carrying genuinely uncapped full-speed data would lose money on the first customer who tethered a laptop and left a cloud backup running overnight. Fair use policies are what make the price on the page possible at all.
That isn't a defence of vague wording — it's why the wording is vague industry-wide rather than at one company. The reasonable thing to ask for isn't unlimited-with-no-policy. It's tell me the policy before I pay.
What to check before buying an unlimited plan
- Is there a published threshold? If the product page says "unlimited" and the terms say "fair use" with no number anywhere, you are buying an unknown.
- What is the reduced speed? A throttle you can still navigate on is a different product from one you can't load a boarding pass on.
- Is hotspot included, and metered separately? If you work off a laptop, this question decides the purchase on its own.
- Does the limit reset? A daily cycle is very different from one throttle that lasts the rest of your trip.
When unlimited is the right buy — and when it isn't
| Your trip | Better fit |
|---|---|
| Video calls, streaming or uploads for hours a day | An unlimited plan — if its policy is published and the throttled speed is usable |
| Maps, messaging, the occasional photo upload | A fixed allowance; you'd likely never reach the threshold anyway |
| Tethering a laptop for work | Check the hotspot rule first — it settles this by itself |
| You want to know exactly what you bought | A fixed allowance, where the number is simply the number |
For most travellers a fixed allowance is easier to reason about, and working out your own daily number usually produces something smaller than the anxiety suggested.
Where we stand
When a plan in the VamosData catalogue is sold as unlimited, it's subject to the destination operator's fair use policy in exactly the way described above. That policy is set by the local network, not by us, and it varies by country and by plan — which is why the honest move is disclosure rather than a promise we don't control.
So where the operator gives us a fair use policy for a plan, it's printed on the plan itself: a Fair Use line on the plan card on the destinations page, alongside the speed and the validity — before you pay, not after. Our terms and conditions say the same in plain language rather than burying it. And where an operator publishes no policy, we don't invent one; you'll know that too, because the line simply isn't there.
"Unlimited" isn't a lie. It's a promise about one specific thing — that nothing will hard-stop your data — dressed up as a promise about everything. Read it as the narrow claim it is, find the policy before you pay, and it stops being a surprise on day four.
Still weighing up plans? Our honest comparison with the local SIM card covers the other half of the decision.