Your business has offices in Sydney and Melbourne. A customer in Brisbane calls your 1300 number. Which team answers?
Without geographic routing, the answer is "whoever you've set as the default." With geographic routing, the answer is "the team closest to or responsible for Queensland."
That distinction is the entire point. Geographic call routing is the mechanism that makes a single national number behave differently depending on where the call originates. For multi-location Australian businesses, it eliminates the need to publish separate state or city phone numbers while still ensuring callers reach the right team — automatically, before anyone picks up the phone.
This article explains how geographic routing works at a technical level, the three granularity levels available in Australia, the important limitation that applies to mobile callers, and when postcode-based routing is a better fit. If you're evaluating how to configure your 1300 or 1800 number for a team spread across states or territories, this is the right place to start.
How Geographic Call Routing Works
Understanding geographic routing starts with understanding how Australia's telephone network identifies where a call is coming from.
When a call is placed to a 1300 number or 1800 number from a fixed landline, the carrier identifies the local exchange the call originates from. Australia's telephone network is built on Telstra's exchange infrastructure. Each exchange corresponds to a geographic location — a suburb, a cluster of suburbs, or a rural region. The routing system maps that exchange to a location and applies the matching rule.
For example, a landline call placed from Bondi Junction routes through a Sydney exchange. Geographic routing reads that exchange, identifies the call as originating in Sydney or NSW, and directs it to the destination you've configured for that location.
For mobile callers, the mechanism is fundamentally different. Mobile numbers in Australia carry the state where the SIM was originally registered — not where the caller is physically located at the time of the call. This is a critical distinction that the rest of this article will return to. For now, understand that carrier-based geographic routing for mobile callers is derived from registration data, not real-time location.
This is how geographic routing differs from general inbound call routing. Standard call routing sends all callers through a single configured path. Geographic routing adds a location layer that evaluates the origin of each call before deciding which path to apply. The result is one number, multiple destinations, determined automatically.
For a broader primer on the category, see What Is Call Routing and 1300 Number Call Routing Explained.
The Three Granularity Levels Available in Australia
Australian geographic routing systems typically offer three levels of location granularity. The right level depends on how your business is structured — specifically, how precisely you need to divide your caller base.
State-Based Routing
State-based routing is the most commonly used configuration for multi-location businesses. It divides Australia into its states and territories — NSW, VIC, QLD, SA, WA, TAS, ACT, NT — and routes each caller to a destination based on the state their call originates from.
Example configuration:
- Calls from NSW route to the Sydney office
- Calls from VIC route to the Melbourne office
- Calls from QLD route to the Brisbane office
- Calls from all other states route to a national team or a default queue
State-based routing is straightforward to configure, easy to audit, and appropriate for businesses that simply want Sydney callers handled by Sydney staff and Melbourne callers handled by Melbourne staff. If your business structure aligns with state boundaries — which is common in Australia, given that most major companies organise operations by state — this is the right starting point.
Region-Based Routing
Australia is divided into approximately 208 telecommunications regions beneath state level. Region-based routing allows you to route callers based on these sub-state regions rather than the state as a whole.
This level is particularly useful for:
- Territory-based sales teams where a single state contains multiple sales territories
- Franchise networks where franchisees hold geographic zones that don't follow state lines
- Businesses that distinguish between metropolitan and regional callers within the same state
For example, a business might route metro Sydney callers to one team and regional NSW callers — covering areas like Newcastle, Wollongong, or the Central West — to a different team. Region-based routing makes that split possible without requiring separate phone numbers.
Exchange-Based Routing
Exchange-based routing uses Telstra's full exchange database, which contains approximately 5,283 exchanges across Australia. Each exchange corresponds to a precise geographic area — typically a suburb or small cluster of suburbs in metro areas, or a town in regional Australia.
This is the maximum granularity available for landline callers. It allows routing decisions at a suburb level, which is relevant for businesses that have offices within the same city and need to direct callers to their nearest location.
For instance, a business with offices in Sydney's CBD and on the Northern Beaches could use exchange-based routing to send callers from inner-city exchanges to the CBD office and callers from Northern Beaches exchanges to the northern office — all through a single 1300 number.
The trade-off is configuration complexity. Exchange-based routing requires mapping thousands of exchanges to destinations, which is typically handled by the routing platform rather than manually by the business. It is also only as accurate as the exchange data for landline callers — the mobile caller limitation applies at all three granularity levels.
The Mobile Caller Problem: The Critical Australian Nuance
This is the most important limitation to understand before deploying geographic call routing, and it is routinely underexplained.
Mobile numbers in Australia are not tied to a physical location. When a SIM is activated, it is registered to a state — typically the state where the person lived or purchased the SIM at the time. That registration state is what carrier-based geographic routing reads.
It does not read where the caller is when they dial. It does not update when the caller moves cities or states. It reads the state of registration from when the SIM was activated.
A customer who activated their Optus number in Melbourne five years ago but relocated to Perth will be identified as a Victorian caller by state-based routing. They will be sent to your Melbourne team. There is no way for the routing system to know they are in Perth.
For some businesses, this limitation is acceptable:
- B2B businesses where the majority of inbound calls come from office landlines
- Businesses serving older demographics who predominantly use fixed-line phones
- Categories where geographic mismatches are low-stakes — for example, businesses with teams that operate nationally and can handle cross-state calls
For other businesses — particularly consumer-facing ones where the majority of inbound calls come from mobile — this limitation is significant.
Solutions for Mobile-Heavy Caller Populations
IVR as a supplement. After geographic routing attempts to match and route the call, an IVR prompt can be triggered for callers who weren't matched correctly or whose routing is uncertain. For example: "If you're not calling from State, press 1 to select your state." This adds a manual correction step without requiring all callers to self-identify. See IVR vs Auto Attendant for more on how IVR layers into a routing configuration.
Postcode prompt via IVR. An IVR system asks the caller to enter their postcode using their keypad. The routing system maps that postcode to the correct destination and transfers the call accordingly. This approach bypasses the mobile registration problem entirely, because the caller supplies their location rather than the carrier inferring it. It adds friction but delivers accuracy.
The right approach depends on your audience, your tolerance for routing errors, and how your teams are structured to handle misrouted calls.
Postcode Routing: The Alternative for Mobile-Heavy Audiences
Postcode routing is an IVR-based alternative to carrier-detected geographic routing. Rather than inferring location from exchange or registration data, the system asks the caller to enter their postcode at the start of the call. That postcode is mapped to a destination and the call is transferred.
This approach is more accurate for mobile callers because it does not rely on registration state. A caller who moved from Melbourne to Brisbane three years ago will enter a Brisbane postcode and reach the Queensland team, regardless of where their mobile number was originally registered.
Postcode routing is particularly well-suited to:
- Franchise networks where franchisees hold tightly defined postcode-based territories
- Field service businesses where technicians or reps are assigned to specific postcode zones
- Insurance and utilities where territory boundaries are drawn at a postcode level
The trade-off is caller friction. Entering a postcode adds time and keypad interaction to the call experience, which some callers find inconvenient. For businesses with simple two- or three-state routing, the friction of postcode entry is unlikely to be worth the accuracy gain. For businesses where misrouting a caller to the wrong territory has commercial consequences — such as franchise revenue attribution — the accuracy is worth it.
Postcode routing can also be used as a fallback layer rather than the primary routing mechanism. Carrier-based geographic routing handles the bulk of calls with no friction; postcode prompt is offered only when the system cannot confidently determine the caller's location.
Real-World Examples
National Trade Franchise
A plumbing franchise operates across NSW, VIC, and QLD. The national 1300 number uses state-based routing: NSW callers route to the Sydney franchisee group, VIC callers route to Melbourne, QLD callers route to Brisbane. Callers from other states, or mobile callers who can't be reliably matched, are sent to a national IVR that prompts them to select their state from a menu. The system is simple to maintain and aligns with how franchisees are organised.
Law Firm With Multiple City Offices
A mid-size law firm has a CBD office in Sydney and a second office in Dee Why serving the Northern Beaches. Both offices handle different client catchments. Exchange-based routing sends callers from inner-Sydney exchanges — Surry Hills, Pyrmont, Newtown — to the CBD office, and callers from Northern Beaches exchanges — Manly, Brookvale, Dee Why — to the northern office. Callers from other areas reach a central reception team. A single 1300 number serves both offices without any manual transfer step.
Insurance Company With Rural and Metro Segments
A regional insurance provider has two claims teams: one specialising in metro Sydney policies, one specialising in rural NSW clients — farming properties, regional businesses, country homes. Region-based routing sends callers from the Sydney metro region to the metro team and callers from regional NSW regions to the specialist rural team. The rural team has specific product knowledge that metro staff don't — routing ensures callers reach the right expertise without being asked to identify themselves.
What Geographic Routing Cannot Do
Geographic routing is a powerful configuration layer, but it has defined limits. Businesses that misunderstand these limits often end up with configurations that underperform expectations.
It cannot identify the physical location of a mobile caller in real time. PSTN-based routing reads network registration data, not GPS or IP location. Real-time mobile location requires an app-based solution, not a phone number routing configuration.
It cannot route international callers geographically. Australian 1300 and 1800 numbers are not reliably accessible from international numbers, and international calls do not carry exchange or registration data that maps to Australian geographic routing rules. International callers to a 1300 number may reach a default destination or not connect at all.
It cannot replace IVR when your caller population is predominantly mobile. If the large majority of your callers use mobile phones, carrier-based geographic routing will frequently misidentify their location based on registration state. In high-mobile-volume scenarios, IVR-based postcode routing or a manual IVR state selection is more reliable than relying solely on carrier detection.
It cannot compensate for poor call destination design. Geographic routing gets the caller to the right team. What happens after that — queue lengths, agent skills, call handling — is a separate layer. Routing callers to the right state team and then leaving them on hold for ten minutes is a routing success and a customer experience failure.
Geographic Routing on Pickle's 1300 and 1800 Numbers
Pickle provides geographic call routing on 1300 and 1800 numbers as part of its business phone number configurations.
State-based routing is available as standard. Region-based and exchange-based routing are also available for businesses that need finer granularity — contact Pickle's team to discuss configuration at those levels.
IVR with postcode prompt is available as a mobile-caller workaround, either as the primary routing mechanism or as a fallback layer within a broader routing setup.
If you're running multiple locations across different states, or managing a franchise or territory-based field team, geographic routing on a single national number is worth configuring correctly from the outset. Pickle's team can advise on the right granularity level for your business structure.
Call 1300 688 588 or email [email protected] to discuss your configuration.
Frequently Asked Questions
Q: Can geographic routing tell where a mobile caller is physically located?
A: No. Carrier-based geographic routing reads the state where a mobile number was originally registered, not the caller's current physical location. A caller who activated their number in Victoria but now lives in Queensland will be identified as a Victorian caller. Real-time location data requires app-based technology, not PSTN routing. If accurate mobile caller location is critical to your routing, postcode-based IVR routing is the more reliable option.
Q: Does geographic routing work with 1300 numbers?
A: Yes. Geographic routing is available on both 1300 and 1800 numbers. The routing logic works the same way across both number types — the carrier identifies the originating exchange or mobile registration state and applies your configured routing rules.
Q: What happens to calls that can't be matched geographically?
A: Calls that cannot be matched to a configured geographic destination — for example, callers from a state you haven't configured a specific rule for — are directed to a fallback destination. This is typically a default national number, a central reception queue, or an IVR that prompts the caller to self-identify. How you configure the fallback is part of the routing setup and should account for the proportion of callers you expect to land there.
Q: Can I use both geographic routing and time-of-day routing on the same number?
A: Yes. Geographic routing and time-of-day routing can be layered on the same 1300 or 1800 number. A common configuration is to apply geographic routing first — routing callers by state to the appropriate office — and then apply time-of-day rules within each geographic destination, so that after-hours calls from that state route to an answering service or message bank rather than an unstaffed team.
Q: How do I handle callers from states where I don't have an office?
A: This is a fallback routing question. Options include routing those callers to your closest office, routing them to a national team that handles all non-primary-state calls, or routing them through an IVR that asks them to confirm their location and presents the most relevant option. The right choice depends on how different the needs of callers from those states are and whether any of your existing teams can serve them effectively.