Leased line vs broadband: which one does your business actually need?
One of the questions we get asked most, usually right after someone's been quoted for a leased line and nearly fallen off their chair. Here's how we answer it.
Why "1Gbps" doesn't tell you much
Broadband, even full fibre, is shared with your neighbours further up the network. The speed you get at 9am on a Monday can be very different to 9pm on a Sunday, upload is usually a fraction of download, and when it breaks you're in the queue with everyone else.
A leased line is a dedicated connection from your office to the provider. Nobody else uses it. Same speed both ways, all day, with a contract that says how quickly it gets fixed.
So the real question isn't how fast. It's what happens to your business when the connection drops, and how long you can live with that.
Broadband vs leased line, side by side
| Full-fibre broadband | Leased line | |
|---|---|---|
| Who else uses it | Shared with other customers | Nobody, it's dedicated to you |
| Upload vs download | Upload usually much slower | Same speed both ways |
| Busy times | Can slow at peak hours | Stays the same |
| If it breaks | Best effort, often next working day or longer | Guaranteed fix time, usually hours |
| Time to install | Days to a few weeks | Around three months, longer if digging is needed |
| Monthly cost | Tens of pounds | Several hundred pounds |
| Set-up surprises | Rare | Possible construction charges after the survey |
| Best for | Most offices, as long as there's a backup | Offices where downtime costs real money, or that need guaranteed upload and fix times |
Typical ranges, not quotes. Prices and lead times vary a lot by building and location.
Which one fits
Broadband is usually enough if:
- A few hours offline would be annoying, not a disaster
- Your team mostly uses email, Microsoft 365 and web apps
- You download far more than you upload
- Full fibre is available in your building, and you've got a 4G/5G or second line backup
A leased line is worth it if:
- An outage stops the business: no calls, no systems, staff sat waiting
- Your phones run over the internet and you can't miss calls
- You upload a lot: large files, cloud backups, video
- Clients or contracts expect you back up within hours, not days
- Full fibre isn't available, or isn't reliable, where you are
The quick test
Work out what a day without internet costs you: wages for people who can't work, missed calls, slipped deadlines. If that's more than the extra a leased line costs each month, it pays for itself the first time something goes wrong. If it isn't, spend the money on good broadband and a backup instead.
Either way, have a backup. A leased line is reliable, not invincible.
If you do go leased line, plan ahead
We've just ordered one for a client moving office, with a backup alongside it. Here's what the process actually looks like.
Before anyone gives you an install date, the provider surveys the building. That survey decides whether there are extra construction charges and whether they need the landlord's permission to run cables. Only then do you get a committed date, and cancelling after that costs money.
They'll also ask for things most people don't have to hand:
- Access to the comms room, risers and rack on install day
- Two free power sockets next to where the kit goes
- Your landlord or managing agent's contact details
- The building's asbestos register, if it was built before 2000
Allow around three months from order to live, longer if digging is needed. Moving office? Order the line before you fix a move-in date, and make sure the backup is live from day one in case the main line is late.
Five questions to decide
- Would a day offline cost more than a few hundred pounds?
- Do your phones run over the internet?
- Do you regularly upload large files or back up to the cloud?
- Is full fibre unavailable or unreliable in your building?
- Do clients or contracts expect you back online within hours?
Mostly yes, a leased line is probably worth it. Mostly no, good broadband and a backup is the smarter spend.