What broadband speed do I actually need?

Speed is measured in megabits per second, Mbps, and the only question that matters is how much your home pulls down at its busiest moment, not on average. Here is the rough shape of it.

For one or two people doing normal things, web, email, social media, a bit of HD telly, 30 to 50 Mbps is comfortable. For a typical household of three or four with several devices going at once, 100 Mbps is the sweet spot and rarely the bottleneck. For a full house that streams in 4K on multiple screens, games online and has two people on video calls all afternoon, 200 to 300 Mbps gives you headroom you will actually feel. Beyond that you are buying a number, not an experience.

If you already know roughly where you land, here is what those speeds cost right now, from the cheapest going to the genuinely silly end.

The mistake every speed guide makes is counting people. What actually matters is how many things are pulling data at the same moment, because that is what divides up your line. A house of five who are never online together needs less than a house of two who both work from home and stream in the evening.

So add up your busiest moment, not your household. The maths is simpler than the adverts suggest. A 4K stream takes about 25 Mbps. An HD stream takes about 5. A video call wants roughly 5 Mbps each way. Online gaming barely sips, around 3 to 10 Mbps. A pile of smart-home gadgets, the doorbell, the speakers, the thermostat, together add up to very little. Stack your worst-case evening, add a bit of slack, and you have your number. For most homes that sum lands comfortably under 200 Mbps.

Streaming is the big one, and it is smaller than people think. Netflix, Disney+ and iPlayer need about 5 Mbps for HD and about 25 for 4K. The catch is multiplied streams: two tellies on 4K is 50 Mbps, three is 75 and that is the realistic ceiling for most living rooms on a Saturday night. Even then, 100 Mbps swallows it.

Working from home is gentler than its reputation. A video call on Teams or Zoom uses around 5 Mbps in each direction, and the rest of the office day, email, documents, the odd large file, is a rounding error. The thing that bites home workers is not download speed, it is upload, which we will come to, and Wi-Fi reaching the spare room, which is a different problem with fixes of its own.

Gaming is the most misunderstood of the lot. A console or PC downloads at whatever speed you give it, so big game updates land faster on a quick line, but the actual playing barely touches your bandwidth, often under 10 Mbps. What gaming needs is low latency, the lag between your button and the server, and that is a different number entirely.

Every advert shouts about download speed and goes quiet on upload, because on the old part-copper lines upload was feeble and providers would rather you did not look. Upload is the speed of everything you send out: your half of a video call, photos backing up, a big file going to a client, a game stream going live.

On older FTTC lines you might get 50 Mbps down and only 10 up, which is why your video call freezes while everyone else's looks fine. Full fibre changes this, because most full-fibre lines are symmetric or close to it, the same speed up as down. If you work from home or upload anything regularly, the upload figure matters more than the headline download, and it is the single best reason to move off copper. Which line you can actually get is worth checking, because FTTC, cable and full fibre have very different ceilings.

Yes, 100 Mbps is fast, and for most homes it is more than enough. It will run several 4K streams, a couple of video calls and a gaming session at the same time without anyone noticing a problem. If your home feels slow on 100 Mbps, the cause is almost always Wi-Fi or an old router, not the line, and a bigger package will not fix it. That is worth saying twice, because it is the exact mistake the upgrade button is designed to encourage.

Gigabit, the 1,000 Mbps package, is available to most of the country now, and most of the country does not need it. It earns its keep in a small number of homes: lots of simultaneous 4K, frequent huge downloads, several people doing heavy creative work at once. For everyone else it is a bigger number on the bill that the household will never convert into anything they can feel. Buy gigabit because you genuinely have the load for it, not because the page told you faster is better. Faster is only better up to the point your home stops using it, and most homes stopped a long way back. Sorry, every comparison site with a "fastest deals" badge sorted by commission.

You do not have to guess. Three quick steps settle it. First, run a speed test on your current line so you know what you are actually getting versus what you pay for, and do it wired in if you can. Second, list your worst-case evening and add up the activities using the numbers above. Third, compare the two. If you already have more speed than your busy evening needs and things still feel slow, the problem is your Wi-Fi or your hardware, and the first thing to rule out is whether your router is the problem. If your line genuinely cannot cover your evening, then and only then is it time to look at a faster package.

So before you tap upgrade, work out the number you actually need. For most homes it is smaller and cheaper than the one being advertised, and it takes about a minute to check whether you are already paying over the odds for the line you have.