Static IP or Dynamic IP for Business NBN? What Actually Changes When You Switch
If you’re setting up or reviewing a business NBN connection in Australia, you’ll hit one question fast: do you need a static IP, or is the standard dynamic IP fine? Most guides tell you static IPs “stay the same” and leave it there. That doesn’t help you decide. What you actually want to know is what breaks without one and whether that matters for your business. Here’s the straight answer first. A static IP is a fixed public address that never changes; a dynamic IP changes over time and is usually shared behind CGNAT. For general web browsing and email, a dynamic IP is fine. But if you run a VPN, remote access, a hosted server, remote CCTV, or any system that whitelists your IP, you’ll likely need a static IP otherwise these services drop out whenever your IP changes. Let’s break down exactly what changes when you switch, who needs it, and what it costs in Australia. What is a Static IP vs a Dynamic IP? An IP address is your business’s address on the internet how other systems find and connect to you. Static IP vs dynamic IP – which is better for business? It depends on what you run. Dynamic IP suits simple setups that only browse, email and use cloud apps. Static IP is better for any business that hosts services, needs reliable remote access, or connects to systems that only allow approved IP addresses. Most businesses with remote workers or on-site servers benefit from static. There’s also a middle option some providers push a “public” or “sticky” dynamic IP that rarely changes. Be careful: it can still change without warning, so it’s not safe for anything that depends on a fixed address. What actually breaks without a static IP? This is the part most competitor guides skip. On a dynamic IP especially one behind CGNAT (more on that below) these are the services that commonly stop working: What breaks on a business NBN without a static IP? VPNs, remote access, hosted servers, remote CCTV viewing, and any system that whitelists your IP. Without a fixed address, these connections drop whenever the IP changes causing lockouts, failed remote logins, and unreachable services. That’s why businesses running these tools switch to a static IP. What is CGNAT, and why does it matter for business NBN? Here’s the hidden reason dynamic IPs break things and it’s not the IP changing, it’s CGNAT. CGNAT (Carrier-Grade Network Address Translation) is a system providers use to share one public IPv4 address across many customers, because Australia has run out of spare IPv4 addresses. Most residential and many standard NBN connections sit behind CGNAT by default. The problem: CGNAT blocks inbound connections. That means port forwarding, hosting, and most remote-access setups simply won’t work even if your IP looks stable. Does CGNAT affect business internet? Yes. CGNAT stops inbound connections, which breaks port forwarding, remote access, hosted servers and remote CCTV. Buying a static IP removes you from CGNAT and gives you a dedicated, reachable public address. Most Australian providers charge a small monthly fee, or include it free on business plans. Some providers offer IPv6 as a workaround, but IPv6 isn’t universally supported yet, so a static IPv4 remains the reliable fix for Australian businesses. Does your business actually need a static IP? Use this quick test. You likely need a static IP if you: You’re probably fine on a dynamic IP if you only: Do I need a static IP for remote work? Often, yes. If remote staff connect through a VPN or access an office server or desktop, a static IP keeps that connection stable. If your team only uses cloud apps (Microsoft 365, Google Workspace) with no VPN or on-site server, a dynamic IP is usually enough. Static IP vs Dynamic IP: side-by-side Feature Dynamic IP (standard) Static IP Address changes over time Yes No — fixed Usually behind CGNAT Yes No VPN / site-to-site Unreliable Reliable Remote access to network Often blocked Works Host a server No Yes Remote CCTV viewing Often blocked Works IP whitelisting Breaks on change Works Typical cost (AU) Included ~$5–$10/mo, or free on business plans Best for Browsing, cloud apps Remote access, hosting, security How much does a static IP cost on business NBN in Australia? The good news: it’s cheap, and often free on the right plan. How much does a static IP cost in Australia? A static IP typically costs around $5–$10 per month as an add-on with most Australian NBN providers. Many business NBN plans include a static IP at no extra cost, alongside priority fault response. If you need one, choosing a business plan that bundles it is usually better value than adding it to a residential plan. A few things worth knowing: Do business NBN plans include a static IP? Many do and this is a key reason to choose a business plan over a cheaper residential one. Beyond the static IP, business plans typically add: For a business that depends on uptime, those extras matter more than saving a few dollars a month on a consumer plan. What actually changes when you switch to a static IP? Switching is simple, but here’s what to expect: What changes when I switch to a static IP? Your IP becomes fixed, you leave CGNAT, and inbound connections start working. Remote access, VPNs and hosted services become reliable. In return, you should tighten firewall and security settings, because a fixed, reachable address needs proper protection. Static IP and security: what to watch A static IP makes your business reachable which is the point, but also the risk. A fixed public address is easier for attackers to find and probe. So when you switch: Done right, a static IP is safe and reliable. Done carelessly, it’s an open door. This is where working with a provider who handles both the connection and the security pays off. Byteway Expert Insight When we onboard Melbourne businesses onto business NBN, the static-IP conversation









