Business Broadband vs Leased Line: Which Do You Need?
Business Broadband vs Leased Line: Which Does Your Business Need?
Last updated: 13 November 2026
Ten years ago, a slow internet connection meant emails took a little longer to send. Today it can mean phone calls that break up, files that won’t open, and a team that can’t work at all. With email, files, phones and business software all running in the cloud, your internet connection has quietly become one of the most important things your business pays for.
When it’s time to choose one, there are two main options: business broadband or a leased line. They can look similar on paper, but they’re built very differently, priced very differently, and suit very different businesses. This guide explains the difference and how to decide.
Broadband vs Leased Line at a Glance
- Business broadband is shared, cheaper, quick to install, and faster for downloads than uploads.
- A leased line is a dedicated fibre connection for your business alone, with the same speed both ways and repairs measured in hours.
- Cost: broadband usually costs tens of pounds a month; a leased line typically starts at around £200 a month.
- Installation: broadband takes days to a few weeks; a leased line typically takes 30 to 90 working days.
- The deciding question: what does an hour without internet cost your business?
What Business Broadband Is
Business broadband is the same underlying technology as home broadband, sold with business-level support. It comes in two main forms:
- Fibre to the cabinet, where fibre runs to the green street cabinet and the last stretch to your building is copper. Speeds depend on how far you are from the cabinet.
- Full fibre (FTTP), where fibre runs all the way into your building. It’s much faster and more reliable, and now available at most business addresses.
Two things define broadband. First, it’s shared: your connection shares capacity with other users, so speeds can dip at busy times. Second, it’s asymmetric: upload speeds are usually much lower than download speeds, which matters for video calls, sending large files and cloud backups. Repairs are typically targeted for the next working day.
What a Leased Line Is
A leased line is a dedicated fibre connection between your premises and the provider’s network, reserved for your business alone. Because nobody else shares it, you get the speed you pay for, all day, every day.
Leased lines are symmetrical, so uploads are as fast as downloads. They come with a service level agreement that commits the provider to fixing faults within a set number of hours, often around four to six, with service credits if they miss it. They can also be upgraded easily: a line installed with spare capacity can usually be sped up later without new installation work.
Side by Side
| Business broadband | Leased line | |
|---|---|---|
| Connection | Shared with other users | Dedicated to your business |
| Upload speed | Usually much lower than download | The same as download |
| Busy times | Speeds can dip | Consistent speed |
| Repairs | Usually next working day | Within hours, with service credits |
| Typical cost | Tens of pounds a month | From around £200 a month |
| Installation | Days to a few weeks | Typically 30 to 90 working days |
| Contract | Often 12 to 24 months | Often 36 months |
| Best for | Most small offices and second sites | Businesses that can’t afford to be offline |
The Questions That Decide It
1. What does an hour offline cost you?
This is the question that matters most. Take a team of 15 people with an average cost of £30 an hour each. If the internet stops them working, every hour costs £450 in wages alone, before lost sales or missed calls. A full working day without internet would cost around £3,600. If an outage like that is realistic once or twice a year, the extra cost of a leased line can quickly pay for itself.
2. How much do you rely on the cloud and phones?
If your files, software and phone system all run over the internet, a connection problem stops everything at once. Each VoIP call needs only around 100 kilobits per second, so call volume is rarely the issue; consistency is. A leased line removes the dips that make calls break up at busy times.
3. How much do you upload?
Video calls, cloud backups, sending large files and remote access all depend on upload speed. Teams that do a lot of this often notice the difference from a symmetrical connection more than any change in download speed.
4. How many people and sites?
A small office of a few people is usually well served by full fibre broadband. Larger teams, busy offices and head offices that connect other sites tend to benefit from a leased line.
5. What’s available at your address?
If full fibre isn’t available, the choice changes. Fibre-to-the-cabinet broadband can be slow and less reliable, which can make a leased line worthwhile for a smaller business than you might expect.
Don’t Forget a Backup Connection
Whichever you choose, any single connection can fail, whether it’s a cut cable from roadworks or a fault at the exchange. A backup connection that takes over automatically keeps your business online when that happens.
For many small businesses, the best value is full fibre broadband with an automatic 4G or 5G backup. For businesses on a leased line, a broadband connection is often added as the backup. Either way, a router set up to switch over automatically means most people won’t even notice. Our business connectivity page explains the options we provide.
What It Costs
As a rough guide, business broadband costs from around £25 to a few hundred pounds a month, depending on speed, technology and support level. A leased line typically starts at around £200 a month for 100 Mbps, rising with speed and depending heavily on your location, usually on a 36-month term.
Installation of a leased line is often included, but where fibre has to be brought to your building there can be extra construction charges. That’s why leased line quotes start with a check of your address. When comparing, weigh the monthly difference against what downtime costs you, not just against each other.
How Long It Takes
Broadband can often be live within days, or a few weeks for a new full fibre installation. Leased lines take longer, typically 30 to 90 working days, and more if new ducting or digging is needed.
If you’re moving office, opening a new site or planning to upgrade, start the conversation early. Leased line lead times are one of the most common reasons office moves end up starting on a temporary connection.
What About the PSTN Switch-Off?
If your broadband still depends on a traditional phone line, it’s affected by the closure of the old phone network on 31 January 2027. Broadband that doesn’t need a phone line, such as full fibre or a standalone fibre service, isn’t affected. Our article on what your business needs to do before the switch-off explains what to check, and our CCSW CallOne cloud phones run over whichever connection you choose.
So Which Is Right for You?
Full fibre broadband with a 4G or 5G backup suits most small offices: it’s fast, affordable and quick to install, and the backup covers the occasional outage.
A leased line makes sense when your phones and cloud systems are business-critical, when you have a larger team or a busy head office, when you upload a lot, or when a day offline would cost more than the difference in price over a year.
If you’re not sure, the honest answer is usually to look at your address, your team and what downtime costs you, and the right option becomes clear quickly.
Frequently Asked Questions
Is a leased line faster than full fibre broadband?
Not always on paper, as full fibre broadband can advertise very high download speeds. The difference is that a leased line delivers its full speed in both directions all the time, because it isn’t shared, while broadband speeds can dip at busy times and uploads are usually much slower.
Can I get a leased line anywhere?
Almost anywhere, but the cost and installation time depend on how close fibre already runs to your building. Where new digging is needed, there may be extra construction charges, which is why a survey of your address comes before a firm quote.
What does a fix time in a leased line agreement mean?
It is the provider’s commitment to restore a fault within a set number of hours, often around four to six, with service credits if they miss it. Business broadband usually only carries a target of the next working day.
Do I need a leased line for a VoIP phone system?
Not usually. A good full fibre broadband connection handles VoIP calls comfortably for most small offices, as each call needs only around 100 kilobits per second. A leased line becomes worthwhile when you have many people on calls at once or the phones are critical to the business.
Can we start with broadband and upgrade to a leased line later?
Yes. Many businesses start with full fibre broadband plus a 4G or 5G backup, then move to a leased line as they grow. Bear in mind leased lines take weeks to install, so plan the upgrade well before you need it.
How CCSW Can Help
CCSW supplies business broadband, leased lines and 4G and 5G backup connections to businesses across Cardiff and South Wales, sourced across the market from providers including BT, Sky and CityFibre, so we can recommend what genuinely suits your address rather than one network’s products.
Because we also provide managed IT support, networks and Wi-Fi and cloud phones, we can look after your connection, your office network and your phones together, with one team to call if anything goes wrong.
To find out what’s available at your address, get in touch or call 0333 014 4544. You can also tick business broadband when you get an instant estimate.
