Buffering feels like a broadband problem, and buying more broadband is the obvious response. It is also, most of the time, the wrong one.
Streaming needs remarkably little bandwidth. If a 4K film stalls on a 500 Mbps connection, the missing capacity is not the issue — something between the streaming service and your screen is, and there are only five candidates.
What streaming actually needs
| Quality | Roughly |
|---|---|
| Audio only | 2 Mbps |
| SD video | 3 Mbps |
| HD (1080p) | 5-8 Mbps |
| 4K | 25 Mbps |
| Four 4K streams at once | 100 Mbps |
A single 4K stream on a 500 Mbps connection uses about 5% of it. Something else is going wrong.
The five candidates, in likelihood order
1. Wi-Fi (most of the time)
TVs are frequently the worst-connected devices in the house: often the furthest from the router, often behind furniture, and often with a cheap wireless chip.
The test: stream on a phone standing next to the router. If that is flawless and the TV stutters, it is Wi-Fi, not broadband.
The fix, in order: an Ethernet cable to the TV (best, permanent, about £10), a mesh node near the TV, or moving the router somewhere more central.
Televisions are ideal candidates for wiring — they never move.
2. The TV or streaming stick itself
Built-in smart TV apps are often slow, badly maintained, and running on hardware that was cheap when the set was made. An older TV with a modern streaming stick frequently outperforms the same TV’s own apps by a wide margin.
The test: if one app buffers and another is fine on the same TV, it is the app. If everything on that TV is bad but other devices are fine, it is the TV.
The fix: a current streaming stick, which costs less than a month of most broadband upgrades.
3. Peak-time contention
If it only happens between 7 and 10pm, capacity is being shared with your neighbours.
The test: the same content at 11pm. If it is perfect then, this is contention.
Within limits this is normal. Persistent, severe evening degradation is worth raising with your provider — check the cabled speed at peak against your minimum guaranteed speed, which is the figure with rights attached.
4. Something else in the house eating everything
The console patch again. A single large download saturates the connection and everything else suffers.
The fix: schedule large downloads overnight, and use your router’s QoS if it has one.
5. The streaming service
Occasionally it is genuinely them — a popular launch, a regional problem. Their status page will say, and other services will be fine at the same time.
The diagnosis, in order
- Is it one app or all of them? One app → the app or service. All → your network.
- Is it one device or all of them? One → that device. All → the network.
- Is it all the time or only at peak? Only at peak → contention. All the time → Wi-Fi or the line.
- Test on a cable. If a wired device is fine and wireless is not, it is Wi-Fi. This is the decisive test.
- Only if the wired test is bad at all times is it a broadband problem worth complaining about.
Things that will not help
A faster package, unless the cabled test shows you genuinely cannot sustain 25 Mbps.
A “gaming” or “streaming” router. Marketing. A mesh system helps because it improves coverage, not because of any streaming feature.
Restarting the router repeatedly. Once is a reasonable diagnostic. If it is needed weekly, the router is failing and should be replaced.
A VPN. Adds a hop and usually makes streaming worse, and services increasingly block them.
Buying for a streaming household
How many simultaneous 4K streams do you actually run? Two is 50 Mbps. Even four is 100.
Beyond about 150 Mbps you are not buying a better picture. You are buying faster downloads of other things.
Prioritise consistency over headline speed. Full fibre delivers its number more reliably than copper-based connections, and reliability is what stops buffering.
Wire the television. The single most effective thing in this entire article, and it costs about the same as one month of a package upgrade.
Sources
- ofcom.org.uk — Ofcom — UK Home Broadband Performance
- ofcom.org.uk — Ofcom — speeds, in-home Wi-Fi and minimum guaranteed speeds
- ofcom.org.uk — Ofcom — codes of practice on broadband speeds and the right to exit