How to Set Up Call Forwarding on Telstra, Optus and More (2026)
For a Telstra mobile, the current Telstra instructions show **21*number*11# to forward every voice call and ##21# to cancel. If you want only the calls you miss to reach a backup, Telstra uses **61*number*11# for no answer, **67*number*11# for busy, and **62*number*11# for unreachable. Optus publishes a different no-answer ring-delay format, and Amaysim's app-based forwarding has its own price. This guide covers those differences, a Telstra call forward to mobile, how to divert a landline to a mobile, and how to test a diverted call to an AI receptionist. Codes are useful only after your particular line and plan confirm the setting.
Call forwarding is a carrier feature; a mobile may let you set it through its dial pad, device settings, or the carrier app. A code can return an error, a plan may restrict a destination, or an existing voicemail diversion can take precedence, so always make a test call from another phone. In the common mobile code family, ** starts a setting, ## cancels it, and *# checks status. The destination and any voice-service or timer fields differ by carrier. Fixed-line and business-phone systems have their own instructions and should not be assumed to use mobile codes.
Call Forwarding Codes at a Glance
The four common forwarding types answer different questions: should every call divert, or only calls you cannot answer? The table below is for a Telstra mobile voice service, using the current published syntax; US numbers use different codes, covered in how to forward calls on AT&T, Verizon and T-Mobile. Replace number with the Australian destination including its area code if it is a landline; use the exact number format your carrier accepts.
| What you want | Type | Turn on | Cancel | Check status |
|---|---|---|---|---|
| Forward every call | Unconditional (all calls) | **21*number*11# | ##21# | *#21# |
| Forward unanswered calls | No reply | **61*number*11# | ##61# | *#61# |
| Forward when you are busy | On busy | **67*number*11# | ##67# | *#67# |
| Forward when phone is off/no signal | Not reachable | **62*number*11# | ##62# | *#62# |
A few things to know before you dial: unconditional forwarding means your phone will not ring for incoming calls. No-answer, busy, and unreachable diverts cover different missed-call conditions; busy and unreachable do not necessarily let your phone ring first. You can try setting all three conditional types to the same destination, but test each state and check the active status. Do not use a blanket reset code without understanding whether it will also remove voicemail or other wanted diverts. Telstra documents ##004# specifically for removing its three conditional MessageBank settings; it is not an instruction to erase every business routing rule.
Ring timing is carrier-specific. Optus documents **61*number**20# for a 20-second no-answer divert to another number, with settings from 05 to 30 seconds in five-second steps. Telstra's published extension code **61*101**20# is for MessageBank, not a general instruction for setting an external AI number. If you need a precise delay to an external destination on Telstra, confirm the supported syntax with Telstra and test the outcome.
How to Forward Calls on Telstra
On a Telstra mobile, **21*number*11# is Telstra's published all-calls voice code and ##21# cancels it. To forward a Telstra mobile to another Australian mobile, replace number with that mobile number, for example **21*0412345678*11#, then press Call and wait for confirmation. For no-answer backup, use **61*number*11# and check with *#61#. These are mobile instructions; business SIP, PBX, fixed-line and unusual plan arrangements may use a portal or different controls. Telstra's current guide is the source to check before relying on a code.
For Telstra mobile call forwarding, the codes most owners use are:
- Forward all calls:
**21*number*11#to activate,##21#to cancel,*#21#to check. - Forward missed (unanswered) calls:
**61*number*11#to activate,##61#to cancel,*#61#to check. - Forward when busy:
**67*number*11#to activate,##67#to cancel. - Forward when unreachable:
**62*number*11#to activate,##62#to cancel.
For a Telstra nbn home phone, Telstra separately documents *21number# for immediate forwarding, *61number# for no answer, and *24number# for busy, with #21#, #61#, and #24# to turn each off. A business fixed line may instead be a SIP or hosted-phone service with a portal and different feature codes. Check which service you actually have; the nbn home-phone instructions are not a universal landline standard.
How to Set Up Call Forwarding on Optus
Optus uses familiar mobile diversion types, but do not copy Telstra's *11 voice-service suffix into an Optus instruction without checking your plan. Optus's current mobile ring-time guide gives **61*number**XX# for a no-answer divert to another number, where XX is 05, 10, 15, 20, 25, or 30 seconds. For example, **61*0412345678**20# requests a 20-second delay. Confirm activation on the handset and with a second phone.
For an Optus mobile, use the current first-party instructions for the action you need:
- Forward unanswered calls: Optus documents
**61*number**XX#to choose the ring delay to another number. - Forward all, busy, or unreachable calls: manage the applicable diversion through My Optus or confirm the current dial code with Optus support for your service. This guide does not copy legacy or another carrier's code into those settings without a current Optus instruction.
- Cancel a confirmed all-call diversion: Optus's current voicemail troubleshooting page documents
##21#; check that the setting is off afterward.
Optus also lets customers inspect voicemail and diversions in My Optus; a setting change may take time to apply. A failed code does not prove one cause: plan restrictions, a mistyped destination, handset behavior, voicemail, or network settings can all matter. Check the app or support and retest. Optus diversion charges depend on whether the service is postpaid, prepaid, or fixed line; prepaid mobile diversion to a local, national, or mobile number is listed at 10c/minute on that page.
Amaysim and Other Carriers (MVNOs)
Amaysim uses the Optus network, but its own current help page directs customers to set forwarding in My amaysim or the app, or through device settings. Do not assume a Telstra or Optus dial string is supported by every smaller carrier simply because it uses the same radio network. An MVNO can have different account settings, call features, and forwarding rates.
The cost difference is material: Amaysim's published help lists 32c/minute for diverted local Australian landline and mobile calls (a 20c/minute forwarding surcharge plus a 12c/minute standard call rate). That is the carrier's rate, separate from any AI receptionist minutes. Check current inclusions and charges on your own plan before routing all calls. If a setting does not activate or a test call still reaches voicemail, contact the carrier rather than assuming the destination is live. You can see broader mobile-routing considerations in our step-by-step call forwarding setup for Australia.
How to Divert a Landline to a Mobile in Australia
For a Telstra nbn home-phone service, dial *21number# from the handset to forward all calls to an Australian mobile and #21# to cancel. Use the full mobile number, starting with 04. Telstra also documents *61number# for no-answer and *24number# for busy. An Optus home or office line may be provisioned differently; check the exact fixed-line product and its current support instructions before entering a code. We could not verify that one *78/#78 pair applies to all Optus fixed lines, so this guide does not present it as universal.
The nbn home-phone code differs from Telstra's mobile voice code: it starts *21, not **21*, and has no *11 voice suffix. Once forwarding is active, test from another phone and confirm what rings, what caller ID appears, and what happens if the destination is busy. Chaining a landline divert to a mobile and then a second mobile divert to an AI number may add cost or fail under carrier rules. A direct fixed-line divert to the intended answering number may be simpler if your service supports it; ask the carrier which routing and charges apply before stacking two forwarding legs.
How to Divert Missed Calls to an AI Receptionist
For some small businesses, conditional forwarding is more useful than forwarding every call. You keep the chance to answer, while the carrier may divert unanswered, busy, or unreachable calls to a backup number. If that number belongs to an AI receptionist, the agent can answer calls that actually reach it, collect approved details, and offer a booking where the calendar and call workflow allow it. Not every missed call will connect, qualify, or result in an appointment. Voicemail, call waiting, device settings, carrier routing, and outages all deserve a test.
Trillet's AI receptionist can be configured as a backup behind an existing number or to answer every forwarded call. A basic agent can be drafted in about five minutes, but carrier setup and reliable test calls take their own time. The current self-serve plan is $49/month with 150 included voice minutes, then $0.20 per additional minute, plus applicable separately billed SMS and carrier charges. It has a 28-day plan money-back guarantee under the Terms, not a free trial or a promise to refund every ancillary charge. Emailed call summaries help you review what the agent captured; SMS follow-up is a separate capability, not an automatic free summary for every call.
To wire it up, obtain the AI service's forwarding number, choose your carrier's current no-answer and busy instructions, and test them separately. With Trillet, setup shows the forwarding code for your carrier: dial it, or scan the on-screen code with your phone, and wait for the confirmation tone. On Telstra mobile, start with **61*aiNumber*11# for no answer and **67*aiNumber*11# for busy; on Optus, its published ring-timer format is **61*aiNumber**20# for a 20-second no-answer delay. Do not enter an Optus timer string on Telstra without confirming it. Call from another phone, let the line ring past the configured delay, then make a busy-line test. Check the greeting, summary, caller-ID behavior, costs, and a human fallback. The mechanics and outage considerations are covered in our guide to conditional call forwarding that keeps your number and adds an AI backup.
Frequently Asked Questions
What is the Telstra call forwarding code?
For a Telstra mobile voice service, dial **21*number*11# and press Call to forward all calls; ##21# cancels it. For conditional forwarding, Telstra documents **61*number*11# for no answer, **67*number*11# for busy, and **62*number*11# for unreachable. *#21# checks all-call status. Verify your actual line and destination with a test call.
How do I set up a Telstra call forward to my mobile?
From a Telstra mobile, use **21*destination*11# for every voice call or **61*destination*11# for no-answer calls, replacing destination with the Australian mobile number. Press Call, wait for confirmation, and test from a second phone. ##21# cancels all-call forwarding; ##61# cancels no-answer forwarding. Telstra nbn home-phone instructions use different *21number# and *61number# codes.
How do I turn off call forwarding?
On a Telstra mobile, use the matching documented cancellation code: ##21# for all-call, ##61# for no-answer, ##67# for busy, or ##62# for unreachable. A Telstra nbn home phone instead uses #21#, #61#, or #24# for its named forwarding types. Other carriers and business-phone systems can differ. Check status and test after any change; a broad reset may also alter voicemail routing you wanted to keep.
Does Amaysim support call forwarding?
Amaysim documents forwarding through My amaysim, its app, or device settings. Confirm your plan and test the call. Its currently published diverted-call rate for local Australian landlines and mobiles is 32c/minute, separate from your AI service's usage charge; do not assume forwarding is free just because the network is Optus.
How do I divert my landline to my mobile in Australia?
For a Telstra nbn home phone, dial *21number# for immediate forwarding or *61number# for no-answer forwarding, then test the mobile destination. #21# or #61# turns off the corresponding setting. A business SIP or Optus fixed-line service may have different codes or a portal, so identify the exact line product before configuring it.
Do forwarded calls cost extra?
It depends on carrier and plan. Telstra says forwarding is included on plans with unlimited call allowance; Optus lists plan-dependent second-leg charges, including a published 10c/minute local/national/mobile rate for prepaid mobile; Amaysim lists 32c/minute for local Australian landline/mobile diverts. Confirm your own plan and destination. Carrier forwarding charges are separate from any AI receptionist subscription, extra voice minutes, or SMS.
Updated August 2026: added a dedicated section and FAQ for forwarding a Telstra mobile to another number and a guide to diverting a landline to a mobile in Australia. Carrier-specific details were rechecked and corrected in September.
Updated September 2026: aligned Telstra mobile voice-divert codes to its current *11# instructions, distinguished Optus's external-number timer from Telstra's MessageBank timer, removed the unverified universal Optus fixed-line code, and added carrier-specific forwarding costs and test-call cautions; noted that Trillet's setup shows the carrier code to dial or scan, and pointed US readers to the AT&T, Verizon and T-Mobile guide.
