DSL in 2026
ADSL and VDSL run over the copper telephone line. Millions of homes still use them where fibre or cable has not arrived yet. Their main weakness: speed drops with the length of the line between your home and the provider's equipment. Two neighbours on the same plan can get very different speeds.
What ADSL speed is normal?
| Technology | Theoretical maximum | Common real speed |
|---|---|---|
| ADSL2+ | about 20 Mbps | 4 to 15 Mbps depending on distance |
| VDSL2 | up to 50 or 100 Mbps | 20 to 50 Mbps on short lines |
If a cable test shows less than half of your plan, the line or your home wiring is probably at fault.
Causes of slow ADSL
- A faulty or missing ADSL filter on a socket with a phone plugged in.
- A long or poor-quality telephone extension between the socket and the modem.
- A secondary socket instead of the main socket.
- Electrical interference from power supplies, dimmers or a fridge.
- A low sync rate: the modem interface shows the line's real sync speed.
Full guide: slow ADSL: how to improve your speed.
Measure your connection now. Start the test
Should you switch to fibre?
If your result stays under 10 Mbps, if several people share the connection or if you make video calls, fibre changes everything. Compare in fibre or ADSL and estimate your needs with our questionnaire.
Frequently asked questions
Why is my ADSL slower than my neighbour's?
ADSL speed depends on the length and condition of the copper line. A few hundred metres more to the exchange is enough to change the speed.
Will a new modem speed up my ADSL?
Only if the old one is faulty. No modem can exceed the physical limit of the line.
Does Wi-Fi slow down ADSL too?
Rarely, because ADSL speeds are low. With ADSL the bottleneck is almost always the line, not the Wi-Fi.
