What “Unlimited Data” SIM Cards Actually Mean

Almost every travel SIM plan labelled “unlimited” has a full-speed cap, after which it throttles down and keeps going. This guide shows you how to find that threshold in the plan details, and whether the throttled speed is actually usable.

Last updated · ~4 min read

What “Unlimited Data” SIM Cards Actually Mean

“Unlimited” usually doesn't mean full speed the whole time

The industry-standard approach is: full speed for the first X GB, then throttled but still usable indefinitely afterwards. There's nothing wrong with this setup on its own (carriers need to stop a tiny minority of users hogging the towers) — the problem is that a lot of platforms don't spell out where that line sits.

So when you're looking at an “unlimited” plan, the first thing to find is those two numbers: the full-speed allowance and the throttled speed afterwards. If you can't find them, ask — don't guess.

Is the throttled speed actually usable?

Note these are the caps stated in the plan — actual performance also depends on how busy the local towers are.

Throttled speed
Still works for · Won't work for
Around 128 kbps
WhatsApp text, email, simple web pages · Video, photo uploads, video calls
Around 256–384 kbps
Everything above, plus low-quality music streaming, maps · HD video, large file uploads
Around 1 Mbps or above
Day-to-day use is mostly smooth · Multiple people streaming HD video at once

So is “unlimited” worth paying for?

  • Worth it: long trips, usage that's hard to predict, or you don't want to worry about topping up mid-trip — having a “still online even if you blow through it” safety net is worth the premium.
  • Not worth it: short trips, light usage. A total-pool plan at the same price might actually give you more full-speed data than the unlimited plan's full-speed allowance.
  • How to compare: put the unlimited plan's full-speed allowance side by side with a same-priced total-pool plan's total allowance. You'll often find the unlimited plan's full-speed portion is actually smaller.

How we handle this

We don't put “unlimited” in headlines as a selling point. On destination pages, the “plan type” axis lists unlimited alongside daily allowance and total pool as equal options; wherever a plan's terms state a throttle threshold, we show it as-is — we don't strip it out.

If a plan's own description doesn't clearly state that threshold, we won't fill it in ourselves either — message us on WhatsApp and we'll go check with the supplier.

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