BT Business Broadband speeds

BT Business Broadband speed tiers at a glance

BT sells business broadband over three types of line. Which one you can have is decided by the address, not by the plan, so the first job on any quote is to check what has been built to your premises. The table shows the tiers BT lists and the headline download and upload speeds from BT's own tier tables.

Upload figures for Full Fibre 100 and Standard Fibre 38 are given on the quote for your address. BT's business pages also list Full Fibre Gigabit and Full Fibre 1.6 Gigabit plans at some addresses; whether they are available at yours, and through us, is confirmed at quote. See gigabit business broadband.

Two things stand out from the table. Full Fibre is a different class of connection, not just a faster version of the same thing: the top tier is more than ten times the download speed of Standard Fibre 76, and upload rises from up to 19Mbps to up to 104Mbps. And BT Business Broadband Pro and BT Ultra Broadband need fibre of one kind or the other, so a copper-only address is limited to Essential and Enhanced.

What "up to" means: the speeds BT gives for your address

The figures above are headline speeds, which is why they carry "up to". BT describes them as the top speeds a product can provide in certain conditions. What matters for your business is the set of figures BT gives for your address when you check availability and again in the order confirmation:

• Estimated download speed range. BT takes the estimated speeds of the 20th and 80th percentile of customers on the same broadband, then adjusts for congestion at the business peak, which BT defines as 12:00 to 14:00.
• Estimated upload speed range. Worked out the same way for upload.
• Minimum guaranteed download speed. BT calls this the Minimum Guaranteed Access Line Speed (MGAL). It is based on the speed the 10th percentile of customers on the same broadband achieve at the business peak, and it is the figure that BT's Minimum Speed Guarantee is measured against.

BT also notes that the minimum upload speed is not guaranteed under the Ofcom code it follows, and that the maximum speeds you might see off-peak can be higher than the top of the estimated range.

So two businesses on the same street, both ordering Full Fibre 500, can be given slightly different estimates. That is normal. When we quote, we can show you the estimate and the minimum guaranteed figure for your address side by side, so you choose a tier on the numbers that apply to you. Start with checking availability at your address.

Download and upload: why the second number matters

Download speed is how fast data reaches you: opening web pages, downloading files, streaming video, pulling updates. Upload speed is how fast data leaves you: sending large attachments, saving to cloud storage, cloud backups, your side of a video call, CCTV footage sent off site and every voice call on an IP phone system.

Broadband is asymmetric. On every BT broadband tier the upload is a fraction of the download, which is the right shape for a business that mostly consumes data. It becomes a problem when the business creates a lot of data. A design studio, a practice uploading scans, or an office that backs up to the cloud every evening can find that a Standard Fibre line feels slow even though the download figure looks generous, because 19Mbps of upload is shared by everything leaving the building.

That is often the strongest reason to move to BT Business Full Fibre: the step from Standard Fibre 76 to even Full Fibre 150 lifts the upload ceiling, and the higher tiers lift it much further. For a side-by-side view of the two technologies, read FTTC vs FTTP. If you need upload to match download exactly, that is the territory of a leased line, covered below.

What affects the speed you actually get

The speed on your quote is the speed of the access line. The speed a person feels at their desk depends on everything between that line and their screen. BT's own help lists the things that can affect broadband speed, and in our experience they fall into three groups:

• The line itself: line quality, the distance from your premises to the green street cabinet and from the cabinet to the exchange (this matters on copper and Standard Fibre, much less on Full Fibre), and time of day, as networks are busier at peak times.
• Your hub and network: the age and type of hub, the Wi-Fi signal across the premises, how many devices are using Wi-Fi at once, and on copper lines, correct micro-filters and plugging into the main socket rather than an extension.
• The device and what it is doing: older laptops and phones that cannot keep up with a fast line, VPNs, and a website or service that is itself busy.

A new connection also needs time to settle. BT calls the first 10 days the stabilisation period: the equipment works out the best stable speed for your line, so speeds go up and down. BT advises leaving the hub switched on, because turning it off can make the line look unstable and lead to a lower speed being set.

Many "slow broadband" complaints are really Wi-Fi complaints. Smart Hub 3 brings Wi-Fi 6 and supports over 100 compatible devices, and Complete Wi-Fi Plus adds Wi-Fi discs that work with it, backed by BT's coverage guarantee for the main building. Our business Wi-Fi guide covers the options.

Testing your speed and the minimum speed guarantee

If you think your connection is slower than it should be, test it properly before drawing conclusions: wired, at different times of day, with as little else running as possible. BT's help describes speed tests in the BT Business app and My Account for the Smart Hub 2 and Smart Hub, and points customers with other hubs or equipment to the BT Wholesale speed tester. Our guide on how to run a BT Business Broadband speed test walks through it.

If wired tests show your speed below the minimum guaranteed download speed for at least 3 successive days once the stabilisation period is over, report it to BT. Under the Ofcom Business Broadband Speeds Code of Practice, which BT has signed voluntarily, BT has 30 calendar days to fix a speed problem that is its fault. If it cannot, and any other options BT offers are not suitable, you may cancel the broadband without penalty. The steps are on our minimum speed guarantee page.

Choosing a speed tier

More speed costs more, so the aim is a tier that covers your busiest hour with headroom, not the biggest number available. A few rules of thumb we use when advising:

• Size for the busiest hour, not the average day. A morning of video calls, a cloud backup running at lunchtime and staff on the guest network all happen together.
• Look at upload first if you create data. Backups, design files, imaging, CCTV and cloud phones all lean on upload.
• Leave room for growth during the contract. Plans run for a minimum term, so think about the team you expect to have in two or three years. See BT Business Broadband contracts.
• Spend on resilience before raw speed if downtime costs you most. Hybrid Backup keeps you online over 4G if the line fails, which a faster tier will not do.

Our guide to what broadband speed your business needs goes through common uses one by one. If you already have BT Business Broadband and want more speed, see upgrading your BT Business Broadband.

When broadband speed is no longer enough

Some businesses outgrow broadband altogether. The signs are a need for upload as fast as download, bandwidth that is not shared with anyone else, or a service level with tighter fix times than broadband care levels offer. Within BT's broadband range, BT Ultra Broadband adds managed Cisco Meraki security and automatic 4G backup on Standard Fibre 76 and Full Fibre tiers up to 900Mbps, but it uses the same asymmetric access lines.

Beyond that is a leased line: a dedicated, symmetrical connection. Our sister site leased-lines.uk covers BT's BTnet leased lines, and our guide on when to upgrade from broadband to a leased line sets out the signs.

We check which line type reaches your address, show you the estimated and minimum guaranteed speeds for each tier available, and recommend the plan and tier that fit how you work. Pricing depends on the line type, tier, plan, add-ons and contract length, and is confirmed at quote. Contact us to check the speeds at your address.