BT Speed Test

This tool analyzes your BT Broadband connection to verify if it is meeting the "Stay Fast Guarantee" promised in your contract. BT uses two main technologies: Fibre to the Cabinet (FTTC), which uses copper for the last leg, and Full Fibre (FTTP), which connects directly to your home. Your speed test results will vary significantly depending on which of these two you have installed.

While BT Full Fibre is robust,The "slow speed" complaints that are actually caused by the Smart Hub 2 failing over to the 4G backup (Hybrid Connect) or poor placement of Whole Home Wi-Fi discs.

Understanding Your Speed Metrics

When running the test, keep an eye on these three critical indicators:

Download Speed: This is the headline speed. If you are on an FTTC plan (Fibre 1 or 2), speeds often fluctuate based on distance from the green cabinet in the street. Full Fibre plans (100, 500, 900) should deliver consistent speeds regardless of distance.

Upload Speed: Essential for Zoom calls. Unlike some providers, BT’s upload speeds are typically lower than download speeds, even on Full Fibre (e.g., 110 Mbps upload on a 900 Mbps plan). This is standard configuration, not a fault.

Latency (Ping): On BT Full Fibre, ping should be very low (under 20ms). If you see high ping, check if your router is glowing Purple (running on 4G).

What Results Should You Expect?

The "Stay Fast" Benchmark

BT provides a personalized "Stay Fast Guarantee." If your wired speed drops below this number, you are eligible for compensation. Typical benchmarks include:

Download Speed: Should be above your "Handback Threshold" (check your My BT account).

Upload Speed: Generally 10-20% of your download speed.

Stability: The connection should not drop, though Wi-Fi speeds may dip in rooms far from the hub.

If you pay for Full Fibre 900 but get exactly 100 Mbps on a wired test, you are likely using an old Cat5 Ethernet cable or a device with a "Fast Ethernet" port limit.

Why Is Your BT Connection Slow?

Before calling 150, check these common hardware behaviors specific to BT:

The "Purple Light" Trap: If you have BT Halo (Hybrid Connect) and your Smart Hub light is Purple, it means your fibre line is down and you are running on EE 4G backup. This will be significantly slower than your normal broadband.

Disc Placement: If you use BT Complete Wi-Fi Discs, ensure they show a Solid Blue light. An Orange light on a disc means it is too far from the main Hub, reducing speed.

Master Socket (NTE5): On older Fibre 1/2 plans, always connect your Hub to the "Master Socket" (the one with the horizontal split). Extension sockets often reduce speed by 30-50%.

BT Technical Details

How to Get an Accurate Test

Wi-Fi signals struggle to penetrate solid brick walls common in UK homes, making wireless tests unreliable for legal "Stay Fast" claims.

To confirm the actual speed entering your property, connect a Cat6 Ethernet cable directly from the Smart Hub's GigE port to a laptop. Turn off Wi-Fi on the laptop. If this wired test beats your "Stay Fast" guarantee, your line is fine, and you likely need Wi-Fi Discs to fix coverage.

When to Call Support

Contact BT support if you observe these specific faults:

Orange Light: A solid or flashing orange light on the Hub means it is connected to Wi-Fi but not the internet (No IP address).

Purple Light: If the light stays purple for more than 24 hours, your main fibre line is broken.

Guarantee Breach: If wired speeds are consistently below your "Stay Fast Guarantee" found in the My BT app.

You can run a line test instantly via the My BT App or by calling 0800 800 150.