Why Is My Wi-Fi Slow in the Evening? What Changes After Tea

The short answer: broadband that flies all day and crawls at eight in the evening is almost always one of two things, and they are not the same problem. Your broadband line is shared with the rest of your area, and it gets busier at peak times; and your Wi-Fi shares a handful of channels with every router around you, which are all busy in the evening too. Your own house doing the most at once after tea sits on top of both. A speed test on a cable at the router, run in the evening and again during the day, tells you which half to deal with.

Two different things slow down in the evening

It helps to keep them apart from the start, because they have different fixes and different people responsible:

• The line, the broadband coming into your house, is shared with your neighbourhood and is under the most demand in the evening.
• The Wi-Fi, the radio between your router and your devices, competes with every other router nearby for a few channels, and they are all at their busiest in the evening.
• Your house is usually doing the most at once after tea: everyone home, screens on, calls, downloads.

The line at peak times

Broadband is not a private pipe from your house to the internet. The capacity near you is shared, and when the most people in your area are online at the same time, each connection can get less of it. ComReg, the communications regulator, puts it plainly: speeds can be noticeably slower at peak times, and the more devices active at once, the more the line struggles.

If this is what is happening, you will see it even with the Wi-Fi taken out of the picture: a laptop plugged into the router by cable is slower in the evening than it is at ten in the morning. If that evening result is also below the minimum and normally available speeds your contract has to state, it is worth a call to your provider with the figures and the times. Our guide to testing the line against the Wi-Fi shows how to run it.

The neighbours' Wi-Fi crowding the channel

Wi-Fi is radio, and there are only so many channels to go round. The 2.4 GHz band, the one older and cheaper devices use, is the worst for this: TP-Link, which makes routers, describes it as crowded, with few channels and many devices competing. In an estate or an apartment block, your router and a dozen of your neighbours' are all trying to use the same few, and in the evening they are all busy at once. The result is a connection that is fine at the router during the day and stutters in the evening, with nothing wrong with the line at all.

The 5 GHz band avoids most of it, because, as NETGEAR explains, it has far more channels and fewer devices on them, though it does not carry as far through the house. This is the same crowding behind a lot of Wi-Fi that drops in the evening.

Your own house, all on at once

The third piece is simply that the evening is when your house asks the most of the connection. Two televisions streaming, someone on a call, a console downloading an update and phones backing up photos all land in the same couple of hours. Our guides to how much broadband speed you need and to a house with too many devices on it go through how that adds up. Virgin Media Ireland's own advice is to leave large downloads until late at night, when the house and the area have quietened down.

How to tell which one it is

The test is the same one, run at two times of day, with the Wi-Fi taken out of it:

1. Plug a laptop into the router with a network cable.
2. Run a speed test in the quiet of the morning, and note it.
3. Run the same test in the evening, when it feels slow.

If the cabled result drops a lot in the evening, the line is congesting at peak times, and that is the provider's side. If the cabled result holds steady but your phones and laptops still slow down in the evening, the line is fine and the Wi-Fi channels are crowded. The free Wi-Fi check run beside the router and in the room that struggles will show the gap, and whether it is worth going further.

What fixes each

If it is the line at peak times

• Ring your provider with the cabled figures, the times and the dates. Congestion on the line is theirs to carry.
• Check ComReg's Broadband Checker at comreg.ie/broadbandchecker for what else your address can get, in case a different connection in your area is less congested.
• Move the heaviest downloads to late at night, as Virgin Media suggests.

If it is the Wi-Fi channels

• Restart the router, which lets it pick a clearer channel, per Virgin Media.
• Move your main devices onto the 5 GHz band, which is far less crowded.
• If your router lets you set the 2.4 GHz channel by hand, try one away from your neighbours'.
• For rooms a clearer channel cannot reach, carry the connection there by cable to an access point, by powerline, or by a mesh unit linked back by cable. A newer router also handles a busy band better, as our guide to Wi-Fi 6, 6E and 7 explains.

If the evening slowdown is in the Wi-Fi and a clearer channel has not fixed it, our home network assessment measures what the house is actually doing: it tests the broadband at the router by cable, measures every floor, and leaves a working powerline and access point trial on the floor that struggles for three days, with the figures in a written report. It is €395, credited in full against any work, in Dublin and the rest of Leinster.

Frequently asked questions