How to Switch Internet Providers Without Losing a Day's Trading

Changing internet providers is one of those jobs businesses put off for years, usually because of a vague fear that something will go badly wrong on a Monday morning. That fear is reasonable — but the risk is entirely manageable with a proper plan. Here is how to move an office to a new internet service without losing a day's trading.

Know why you're moving before you start

Migrations driven by a specific problem go well. Migrations driven by a cheaper headline price often reproduce the original problem at a lower price. Be clear about which of these you are solving:

• Speed or capacity — the connection is genuinely saturated at peak
• Reliability — frequent dropouts, high latency, packet loss
• Support — faults take too long to resolve and escalation goes nowhere
• Cost — paying for capability you do not use
• Capability — you need a static IP, an SLA, or a service type your current provider does not offer

Note that if your problem is dropouts on an FTTN connection, changing providers may change nothing at all, because the copper between the node and your building is the same regardless of who bills you. Diagnose first.

Step 1: Audit what depends on the connection

Before you touch anything, list everything that would notice. In a typical office this is longer than people expect:

• VoIP phone system and any SIP trunks
• EFTPOS and POS terminals
• Any service accessed via VPN, and any site-to-site VPN tunnel
• Remote access into an office server or NAS
• Security cameras with remote viewing
• Alarm systems with IP monitoring
• Cloud backup jobs
• Anything that relies on your current static IP address
• Building access control, digital signage, smart lighting

That static IP dependency is the big one. If suppliers, banks, or a client's system whitelist your office IP address, changing it without warning locks you out of things. Find every one of these now. The usual suspects are accounting software with IP restrictions, remote desktop gateways, VPN endpoints, mail relay configurations, and DNS records pointing at your office.

Step 2: Choose the new service on the right criteria

Compare on what actually determines your experience:

• Underlying technology. FTTP, FTTC, FTTN, HFC, fixed wireless, Enterprise Ethernet — check what is available at your exact address, not your suburb.
• Upload speed. Business use is upload-heavy. This matters more than the download figure on the advertisement.
• Contention and business-hours performance. Ask about congestion during business hours specifically.
• Fault restoration targets and whether they are contractual.
• Static IP availability and cost.
• Contract term and exit terms.
• Whether support is Australian-based and business-hours staffed.

Also check whether a fibre upgrade path exists at your address. Many commercial premises on older technologies became eligible for subsidised or free fibre upgrades, and businesses routinely miss this simply because nobody asked.

Step 3: The overlap period is the whole trick

Here is the core principle: do not cancel the old service before the new one is proven.

Run both services in parallel for at least two weeks, ideally a full month. Yes, you pay for both. The cost of one month of overlap is trivially less than the cost of a failed cutover during trading hours.

This is straightforward if the two services use different physical infrastructure — for example, keeping your existing fixed-line while a new fibre service is installed, or overlapping a 5G service with a fixed line. Where both services need the same physical connection, discuss the sequencing with both providers in advance, because a straight transfer may leave you without service for a period.

Step 4: Prepare the new service before cutover

With the new connection live but not carrying production traffic:

1. Test it thoroughly. Speed, but more importantly latency and packet loss under sustained load. A connection with good speed and bad jitter will ruin your phone calls.
2. Note the new IP address and confirm whether it is static.
3. Configure your firewall for both WANs. Modern firewalls handle dual WAN natively, letting you fail between them.
4. Update every whitelist you identified in step 1 to include the new IP alongside the old one. Add, do not replace. Remove the old entry weeks later.
5. Update DNS records that point at your office IP, and lower their TTL to five minutes several days beforehand so the change propagates quickly.
6. Pre-build the VPN tunnels on the new connection so they are ready to activate.
7. Test with a pilot group. Move two or three tolerant staff onto the new connection for a few days and see what breaks.

Step 5: Cut over at the right time

Choose a low-impact window. For most businesses that means a Friday evening or an early weekday morning — not Friday at 5pm, and not the day before end of month.

Have on hand: contact numbers for both providers, your IT support, the new service's credentials, and a documented rollback plan. The rollback plan matters most. If something goes wrong at 6am, you want a decision point — "if this is not resolved by 8am, we switch back" — agreed in advance rather than debated under pressure.

Then work through a verification checklist immediately after cutover:

• General internet browsing from several devices
• Email sending and receiving
• A test call in and out on the phone system, checking audio quality both ways
• A live EFTPOS transaction
• VPN connection from an external location
• Remote access to any onsite server or camera system
• Cloud backup job running successfully
• Any whitelisted supplier system

Step 6: Porting phone numbers

If your phone service is moving too, treat this as a separate project with its own timeline. Number porting in Australia takes time and is not instant — simple ports move faster than complex ones involving multiple numbers or hunt groups.

Key points: never cancel the old phone service before the port completes, because cancelling releases the number and you may lose it permanently. Submit porting paperwork with details exactly matching the current account, since mismatches are the main cause of rejection. And plan for a short cutover window where calls may behave unpredictably.

Step 7: Decommission carefully

Only after two to four weeks of stable operation:

• Confirm nothing still depends on the old IP address
• Restore DNS TTLs to normal values
• Cancel the old service in writing and get written confirmation
• Check your final invoice for early termination charges you did not agree to
• Return or dispose of old provider equipment as required
• Update your documentation with the new details

Consider keeping the old service as failover

Before cancelling, ask a different question: could the old connection be downgraded to a cheap plan and kept as automatic failover? For any business where downtime costs real money, having two independent connections with automatic failover is genuinely valuable, and the incremental cost of a basic backup service is small.

This is particularly worth considering for retail and hospitality, where the connection failing means you cannot take payment.

The short version

Audit dependencies, overlap the services, test before you commit, update whitelists additively, cut over in a quiet window with a rollback plan, verify against a checklist, and decommission slowly. Done this way, a provider migration is a non-event that nobody outside IT notices.

Real IT Consulting manages internet and phone migrations for businesses across the Gold Coast, Brisbane, Logan, Pimpama and Sydney, including dependency audits and failover configuration. Call 0489 940 359 to plan yours properly.