Prepaid SIM by data volume: what stands between a big number and a working line
Arriving with a figure in mind — a hundred gigabytes, or anything near it — is a different starting point from arriving with a need. Four things decide whether that figure is reachable on a given prepaid line, and only one of them is about the pack.
A volume is not something you can order
There is no product here called a hundred gigabytes. We sell no SIM cards and no plans, and we publish no list of sizes — what exists is whatever the operator that owns a number publishes for it, in their market, at their price. Enter the number and their current ladder loads; the size you had in mind is either a step on it or it is not.
That makes the figure a starting point rather than an order. Everything below is what has to be true for it to turn into data on a line. Where the line itself comes from is on the prepaid SIM overview, and how to translate a habit into a size — rather than a size into a habit — is on choosing a data size.
Four gates between the number and the line
They have to clear in order, and three of them have nothing to do with how much data you want. The second is the one large buyers miss.
| The gate | Settled by | How to clear it |
|---|---|---|
| The step exists at all | That operator's own ladder, for that market. Sizes are not standardised: a step that is ordinary in one country has no counterpart in the next. | Enter the number and read the list that loads. It is the operator's current catalogue, and neither we nor any other top-up service adds steps to it. |
| The line outlives the pack | The SIM's own validity, which runs on a separate clock from the allowance and is set by the operator. | A large allowance takes weeks to spend, so it needs weeks of line to spend it in. Check the line has that long before committing to the biggest step on the ladder. |
| The terms allow your use | The small print on that specific pack — fair-use ceilings, speed step-downs and whether tethering is permitted at all. | These are the clauses a small pack never reaches. At this size they are the difference between the figure on the label and the data you actually get to use. |
| It can be funded in one order | The checkout: one order goes to one number, with the total shown before you confirm. | There is no basket and no batching. A large step is one payment, and if the operator refuses the load the whole amount comes back. |
The second gate is the one that costs people money. A prepaid line has an expiry of its own, separate from any pack sitting on it, and a big allowance is precisely the kind that takes long enough to spend for the two to collide — the line goes quiet with most of the data unused. How those two clocks run is set out on the prepaid SIM overview and, for a SIM in a device rather than a phone, on the prepaid data SIM page.
Why the small print only starts to bite at this size
A modest pack runs out long before it meets any of its own conditions, so the terms never come up. A large one is bought precisely to be consumed, which is what walks it into the ceiling, the speed step-down or the tethering clause.
None of those are ours to set or to waive — they belong to the operator whose pack it is, and they are in that pack's own terms rather than on the label. Whether tethering is even allowed on a given pack is their rule too. The three ways a generous allowance is usually limited in practice are set out on mobile data bundles, and whether an uncapped pack exists for a number at all is answered on bundle shapes.
Three jobs a large allowance is usually bought for
At this size the line is rarely feeding one phone. Each job has a different thing worth checking first.
A router, standing in for broadband
One line carrying a whole household. The check that matters is the tethering and hotspot rule on that pack, because sharing the connection is the entire point of the arrangement and some packs do not permit it.
Prepaid SIM for devices covers whether a given router SIM is a line you can top up at all.
A tethered laptop for work
Predictable in volume, unforgiving about speed. The check is what happens at the threshold: a step-down that still carries mail and calls is survivable, one that does not is a working day lost.
A laptop also spends an allowance on things nobody asked it to — what quietly eats a bundle goes through those.
A long stay in another country
Here the check is where the allowance is valid. Inclusions are frequently national only, so a large pack bought on a home line may not follow you across a border in the way the figure suggests.
Prepaid travel SIM weighs roaming against buying a local line for the stay.
If the step you wanted is not on the ladder
Common, and not a dead end. The figure was yours; the ladder is theirs. Three ways round it, in the order most people should try them.
Check the ladder for a number- Take the step below and reload it when it runs out. More orders and a worse rate per gigabyte, but nothing is committed up front and nothing expires unused — the cost of each shape works the trade-off through.
- Look at a differently shaped pack rather than a bigger one. A pack fenced to nights or to one kind of traffic can carry far more volume for the same money, if the use fits the fence.
- Ask the operator directly. Some of their largest offers are sold as a tariff rather than as a pack you can buy against a number — prepaid plans and tariffs explains what a top-up does once a line is on one.
- What is not an option is us adding a step. The catalogue that loads is the operator's, unedited, for the number you entered.
Large volumes, question by question
Payment, refunds and delivery questions are answered in the help centre.
Open the help centreDo you sell a 100 GB prepaid SIM?
We sell no SIM cards at all, and no sizes of our own. If the operator that owns a number publishes a step that large for their market, it appears in the list when you enter the number and we deliver it like any other. If they do not, there is nothing on our side that can create it.
Can I combine two packs to reach the volume I want?
Whether a second pack adds to the first, replaces it or queues behind it is the operator's rule and differs by network — we cannot promise any of the three. Each order is one purchase against one number, so buying twice is two orders, priced twice.
Will a large allowance keep the line alive on its own?
Not necessarily. The SIM has an expiry that runs separately from the pack, and on some networks it is activity or a top-up that pushes it out, not an allowance sitting unused. That is the gap a big pack is most likely to fall into.
Is a bigger pack always better value per gigabyte?
Usually, but only if you finish it inside its window — an unspent gigabyte has no value at any price. Which definition of cheap is worth optimising, and how to price the stretch rather than the pack, is set out on cheap data bundles.
The size I bought is not showing on the line. What now?
Give it a few minutes first — most loads land 5 to 60 seconds after payment clears, and every completed order returns the operator's reference code on screen and by email. If the operator rejected it instead, the full amount comes back to your card, with their reason attached.
Where to go next
This page is the volume figure meeting the line. The pages around it pick up each half of it.
For a SIM in a tablet, a router or a dashcam rather than a phone, the loading steps and the data-did-not-appear checks are on the prepaid data SIM page. Which pack shapes exist, and what each one fences off, is on daily, weekly and night packs.
The ladder is one number away.
Enter the line with its country code and that operator's own steps load, with the total on screen before anything is charged.