If you have ever set up remote access to an office server, connected CCTV to an app, or been asked by a software supplier for "your IP address", you have probably come across the term static IP. It sounds technical, but the idea is simple, and many businesses never need one at all.
This guide explains what a static IP address is, how it differs from a dynamic one, and how to work out whether your business needs one.
What is an IP address?
An IP address is a number that identifies a device or connection on a network, a bit like a postal address for data. There are two kinds that matter here.
- Private addresses are used inside your office. Your router gives one to each laptop, phone, printer and till. They only mean something on your own network.
- Public addresses are what the rest of the internet sees. Your router usually has one public address, and all the devices behind it share it when they go online.
When people talk about a static IP for a broadband connection, they mean the public address.
Static vs dynamic IP addresses
Dynamic IP
With a dynamic address, your provider assigns a public address from a pool. It may stay the same for a long time, but it can change, for example after a router restart, a network change or a period offline. For everyday browsing, email and cloud software, you would never notice.
Static IP
A static address is assigned to your connection and does not change. That makes it predictable: other systems can find you at the same address, and you can tell a supplier "only allow connections from this address" and know it will keep working.
Shared addresses
Because the older style of internet address, known as IPv4, is in short supply, some networks share one public address between several customers. This is often called carrier grade NAT. It is fine for browsing, but it can stop some remote access and hosting from working. If you need to reach your office from outside, ask your provider how addresses are handled on your connection.
Does my business need a static IP?
The honest answer for many small businesses is no. If your team works mainly in cloud services such as email, accounting software and file storage, those services do not need to find your office, so a dynamic address is fine.
A static IP starts to make sense when something outside your building needs to connect in, or needs to recognise you reliably.
Common reasons to have one
- Remote access to office systems. If staff connect to a server, file share or desktop in the office from home, a fixed address makes that connection dependable.
- Site to site VPNs. Linking two offices, or an office and a warehouse, is simpler when each end has an address that does not move.
- IP allowlisting. Some banking portals, supplier systems, cloud platforms and payment services let you restrict access to known addresses. That only works if your address stays the same.
- CCTV and building systems. Recorders and access control systems are often reached remotely. Many now use a cloud service instead, but some still expect a fixed address.
- Hosting your own services. Running a mail server, web server or other service in the office usually needs a static address, although most businesses now host these in the cloud instead.
- Some phone systems. Certain VoIP setups use a fixed address to authenticate your office. Many modern hosted systems do not need one, so check with your phone provider. Our guide to VoIP and your broadband covers the other requirements.
When you probably do not need one
- Your staff use Microsoft 365, Google Workspace or other cloud tools.
- Remote access is handled by a cloud based service rather than a server in the office.
- Your phones, tills and CCTV connect out to cloud services and nothing needs to connect in.
Is a static IP address a security risk?
A static address is not, by itself, less secure. Every connection on the internet has a public address that can be scanned. The real question is what you expose.
Problems start when devices or services are opened to the internet through port forwarding, often to make remote access or CCTV work quickly. If those systems are out of date or use weak passwords, a fixed address makes them easier to find again and again.
Good practice with a static IP:
- Open as few ports as possible, and review them regularly.
- Use a VPN for remote access rather than exposing remote desktop or file shares directly.
- Keep your router, firewall and any exposed devices updated.
- Use strong, unique passwords and multi factor authentication wherever it is offered.
Our guide to cyber security basics for your business broadband goes into more detail.
Static IPs, leased lines and backup connections
Leased lines commonly come with a static address or a small block of addresses, because the businesses that choose them often run VPNs, servers or several sites. With business broadband, a static IP may be included or offered as an option, depending on the provider and package.
If you add a backup connection, remember that it will usually have a different public address. Anything that relies on your static IP, such as allowlisting or a site to site VPN, may not work while you are on the backup line unless you plan for it. We explain how in our guide to backup broadband and failover.
What about IPv6?
IPv6 is the newer addressing system, with far more addresses available. Over time it reduces the pressure on public addresses, but not every service, device or network uses it yet. For now, when a supplier asks for your static IP, they almost always mean an IPv4 address.
Questions to ask before you order
- Is a static IP address included, or available as an option, with this package?
- Is it a single address or a block, and do I need more than one?
- Is my connection behind carrier grade NAT if I do not take a static address?
- Will the address stay the same if I upgrade my package or move premises?
Not sure whether you need a static IP?
Tell us what you need to connect to, and we will give you a straight answer. Check your address to see business packages, request a quote for a leased line, or contact our team in Sunderland to talk it through.