Why is my internet slow at night?
You barely notice your connection all day, and then around eight in the evening everything turns to treacle — video drops to a lower quality, pages hesitate, the game starts lagging. It's not your imagination, and it's usually not a fault. It's peak hours, and it has a specific cause.
The short answer: everyone is online at once
Your internet plan's speed is a ceiling, not a promise. Large parts of the network are shared — with your neighbours, and with everyone routing through the same equipment. During the day that shared capacity sits mostly idle. Between roughly 7 and 11 pm, an entire neighbourhood settles in to stream, scroll and game simultaneously, and the shared pipe fills up. When the pipe is crowded, everyone's real-world speed drops below the number on their bill.
There are two places this congestion happens:
- Your ISP's local segment. Cable (and some fibre) neighbourhoods share a node. If your street collectively hammers it every evening, everyone on that node slows down together. This is the classic "slow at night" cause.
- The wider internet and the services themselves. A hugely popular service at 9 pm on a Friday is serving its global peak too. Sometimes the slowdown isn't your line at all — it's the site straining under its own rush hour.
Wi-Fi has its own night-time rush
There's a second, sneakier culprit that has nothing to do with your ISP: your neighbours' Wi-Fi. In a flat or dense street, dozens of routers share a handful of wireless channels. In the evening they all wake up, and the interference alone can gut your speed — even if the connection coming into your home is perfectly fine. This is why the fix is sometimes inside your walls, not out on the street.
How to tell which one it is
Two quick comparisons narrow it down fast:
- Night vs. morning. Run a test during the slow evening window, then again first thing in the morning. Fast in the morning, slow at night = congestion, plain and simple. Slow at both = look at your Wi-Fi, router, or a possible line fault instead.
- Everything vs. one thing. Is the whole internet slow, or just one app? If only Netflix or one game struggles while the rest is fine, that service — not your connection — is having the busy night. Our test settles this by measuring your line and the site at the same time.
Run the 10-second test →
What actually helps
| Fix | Worth it? |
|---|---|
| Use a wired ethernet cable | Yes — skips Wi-Fi congestion entirely, the single biggest easy win |
| Switch to the 5 GHz Wi-Fi band | Yes — far less crowded than 2.4 GHz in dense areas |
| Move closer to the router / add a mesh point | Yes, if evenings are slow because your signal is already weak |
| Upgrade to a faster tier | Yes, if you're genuinely maxing the line every single evening |
| Reboot the router every night | No — it doesn't touch congestion; a nightly ritual is a red herring |
If the slowdown is Wi-Fi interference rather than your subscription, a cable or a better band beats paying for more speed you'll never see — the difference is spelled out in Wi-Fi vs. ethernet. And if you suspect the line itself is just too small for a full house at peak, what counts as a good speed in 2026 gives you the numbers to judge it.
One more suspect: throttling
If your evenings slow down at exactly the same time every night regardless of what you're doing, and especially near a data-cap date, your provider may be shaping traffic. It's less common than plain congestion, but worth knowing about — a test showing normal speeds off-peak and a hard, consistent ceiling on-peak is the fingerprint.