"Uncapped" Explained: Fair Use Policies and Throttling in SA

Capped vs uncapped vs unlimited: the words don't mean what you think

South African ISPs use three labels loosely, and the gap between them is where people get caught out. "Capped" is the clearest: you buy a fixed bundle of data, and when it runs out your line either stops or slows to a crawl until you top up or the month rolls over. "Uncapped" means there's no hard data ceiling — you can download as much as you like — but it usually still comes with rules about how fast and how consistently you get to do it. "Unlimited" is mostly a marketing word, used by both fibre and mobile providers, and it's your cue to go and read the terms.

The useful way to think about it: capped limits how MUCH you use; uncapped (and most "unlimited") plans instead manage HOW you use it — through fair use policies, prioritisation and peak-time shaping. Neither is automatically better. A heavy household that streams 4K, games and works from home wants genuinely uncapped fibre; a light user who mostly browses and messages may pay far less for a generous capped or mobile bundle.

• +Capped — fixed GB bundle, hard stop or slow-down when depleted.
• +Uncapped — no data ceiling, but speed and consistency may be managed.
• +"Unlimited" — marketing term; read the FUP before assuming it's truly limitless.

Fair use policies (FUP): the small print that defines "uncapped"

A fair use policy is the clause that stops one customer from hogging shared capacity. Most uncapped plans in SA fall into two camps. Truly uncapped, unshaped fibre has either no FUP or a very soft one — you can run heavy traffic all day, and the ISP only steps in for genuinely abusive use, such as running a commercial server on a home line. "Soft-FUP" plans set a monthly threshold, and once you cross it your speed is reduced (deprioritised), usually only during busy hours, for the rest of the billing cycle.

The catch is that a soft-FUP plan can still be advertised as "uncapped" because you're never blocked — you're just slowed. That's legal and common; the real question is whether the threshold is high enough that you'll never feel it. A streaming-and-browsing household rarely hits a sensible FUP. A household pulling huge game downloads, running multiple 4K streams and backing up to the cloud is far more likely to.

• +Soft-FUP: full speed up to a threshold, then deprioritised — not cut off.
• +Truly uncapped: no threshold, or one so high normal homes never reach it.
• +"Uncapped" plus a low FUP threshold can behave a lot like a generous capped plan.

Throttling, shaping and prioritisation — how the slow-down actually works

These three words describe different levers, and providers often blur them. Throttling is a deliberate cap on your speed — your line is held at a fixed lower rate because you've crossed an FUP threshold or because it's peak time. Shaping (or traffic shaping) is more surgical: the ISP slows specific types of traffic, classically heavy peer-to-peer or torrent traffic, while leaving browsing and streaming untouched. "Unshaped" plans, common on premium fibre, treat all traffic equally.

Prioritisation is the gentler, more modern approach used on most good uncapped fibre. Nobody gets a hard speed cap; instead, when the network is congested at peak, customers who've used far more than average are temporarily pushed to the back of the queue so the line stays fair for everyone. Outside peak you'd never notice. This is why two people on the "same" uncapped package can have very different experiences — one is a light user always near the front, the other a heavy user occasionally deprioritised when the network is busiest.

• +Throttling — your overall speed is reduced to a fixed lower rate.
• +Shaping — specific traffic types (e.g. torrents) are slowed; others aren't.
• +Prioritisation — heavy users go to the back of the queue only at peak congestion.
• +Peak in SA is typically weekday evenings, when most people are home and streaming.

Why mobile "unlimited" is not the same as fibre uncapped

Mobile uncapped and unlimited deals (LTE and 5G from rain, MTN, Vodacom, Telkom and others) share a radio tower with everyone nearby, so the rules are usually stricter than on fibre. Common patterns include night-time-only uncapped (full freedom overnight, managed during the day), per-day fair use allowances that reset every 24 hours, fixed speed tiers (an unlimited plan locked to a set Mbps regardless of signal), and heavier deprioritisation when the tower is congested.

Mobile signal also varies with distance from the tower, walls, weather and how many neighbours are online — so an "unlimited" SIM can deliver very different real speeds at different times of day, even before any FUP kicks in. Fibre, being a dedicated wired connection into your home, is far more consistent, and it's where "truly uncapped" is most genuinely achievable. For a fixed home, fixed-LTE or 5G is a strong option where fibre isn't available — but read the daily and monthly fair use terms especially carefully, because they're often the real ceiling.

• +Mobile shares a tower — fair use rules are usually tighter than fibre.
• +Watch for: night-only uncapped, per-day allowances, fixed speed tiers, tower deprioritisation.
• +Mobile speed swings with signal, distance and congestion; fibre stays steady.
• +Where fibre exists, it's the more reliable home of "truly uncapped".

How to read the fine print before you buy

You can avoid almost every surprise by checking a handful of things before signing. Most of this lives in the ISP's "Acceptable Use Policy" or "Fair Use Policy" page and the package's terms, not the glossy headline. If a provider won't give you a clear answer, treat that as an answer.

Match the plan to your actual usage, not the biggest number on the page. If you can, run a speed test in the evening on a month-to-month plan before committing long-term, and ask whether the line is shaped or unshaped. Remember that on open-access networks (Openserve, Vumatel, Frogfoot, MetroFibre) the underlying line is the same — what differs between Afrihost, Cool Ideas, Webafrica, Vox and others is the FUP, peak management, support and price.

• +Is there an FUP threshold? If so, what is it in GB, and what happens after — throttle or deprioritise?
• +Is the plan shaped or unshaped? Unshaped treats all traffic equally.
• +Does any slow-down apply all day or only at peak?
• +For mobile: is it night-only, per-day, or a fixed speed tier?
• +Is it month-to-month? Prefer no lock-in so you can test real peak performance and switch ISP on the same fibre line if needed.

Frequently asked questions

Does "uncapped" mean truly unlimited with no slow-downs at all?

Not always. Uncapped means no hard data limit — you won't be cut off or asked to top up. But many uncapped plans still apply a fair use policy or peak-time prioritisation, so heavy users may be slowed during busy evening hours. "Truly uncapped, unshaped" plans, usually premium fibre, are the ones with little or no such management.

Will I actually notice a fair use policy on normal home use?

Most households won't. Browsing, messaging, video calls and even regular HD or 4K streaming rarely trigger a sensible FUP. You're most likely to feel it if you pull very large downloads, run several 4K streams at once, game heavily and back up to the cloud — all on a cheaper plan with a low threshold, during peak time.

What's the difference between throttling and shaping?

Throttling reduces your overall speed to a fixed lower rate. Shaping slows only specific kinds of traffic — classically heavy peer-to-peer or torrent traffic — while leaving browsing and streaming alone. A plan described as "unshaped" treats all traffic equally.

Why is my mobile "unlimited" SIM slower than a friend's fibre?

Mobile data shares a radio tower, so providers manage it harder: night-only uncapped windows, per-day allowances, fixed speed tiers and heavier deprioritisation when the tower is busy. Signal strength, distance and weather also affect real speed. Fibre is a dedicated wired line into your home, so it stays far more consistent.

Where do I find the real rules for a plan?

Check the ISP's Acceptable Use Policy or Fair Use Policy page and the specific package terms, not the headline advert. Look for any GB threshold, whether the line is shaped, whether slow-downs apply all day or only at peak, and (for mobile) whether it's night-only or per-day. If a provider won't give a clear answer, take that as a warning sign.