Optus call forwarding: the codes, and how to turn it off
Optus calls it call diversions. Here are its codes, straight from Optus’s own help pages, with how to test them and how to turn them off again.
The short answer
On an Optus mobile, you forward calls by dialling a code on the keypad and pressing call. **004*04XXXXXXXX**20# rings your phone for 20 seconds, then sends on any call you don’t take. **21*04XXXXXXXX# sends every call straight there.
To turn it off, dial ##002#. You can also set, remove and check diversions in the My Optus app, under Settings, then Voicemail and call diversions.
Swap 04XXXXXXXX for the number you’re sending calls to. The codes are from Optus’s help pages, read on 12 October 2026, and Optus can change them.
The Optus divert codes
Dial them on the phone you’re forwarding and press call. A landline number needs its area code. Overseas, Optus says to enter the number in +61 form.
| Code | Optus page it’s from | |
|---|---|---|
| Turn it on | ||
| Rings you first, then diverts if you don’t answer, you’re on a call or you’ve got no coverage | **004*04XXXXXXXX**20# | Manage call diversions on your Mobile Phone |
| Every call, and your phone doesn’t ring | **21*04XXXXXXXX# | iPhone 17 guide: Divert calls to your voicemail |
| Only when you don’t answer | **61*04XXXXXXXX**20# | How to change the ring time before a call diverts |
| Only when you’re on another call | **67*04XXXXXXXX# | iPhone 17 guide: Divert calls to your voicemail |
| Only when the phone’s off or out of coverage | **62*04XXXXXXXX# | iPhone 17 guide: Divert calls to your voicemail |
| Turn it off | ||
| Turn off one divert | ## then its code then #, like ##004# or ##21# | Manage call diversions on your Mobile Phone |
| Turn off every divert | ##002# | iPhone 17 guide: Cancel all diverts |
| Ring time | ||
| How long it rings first | Change the 20 to 05, 10, 15, 25 or 30 seconds. Optus puts 20 seconds at about 4 to 8 rings | How to change the ring time before a call diverts |
From Optus’s help pages, read on 12 October 2026. Optus’s iPhone guide shows its voicemail number in these codes, and we’ve swapped in 04XXXXXXXX. Optus can change them.
Set it up, then test it
Pick where calls go
Your other mobile, the office, an answering service or voicemail. A landline number needs its area code.
Dial the code
Key it in like a phone number and press call. On an iPhone, Optus’s guide then says to tap Dismiss.
Ring your number from another phone
Borrow a mate’s phone. With a ring-first code, let it ring out and see where the call lands. With code 21, your phone shouldn’t ring at all.
Check it in the app
In the My Optus app, tap Services, your mobile, Settings, then Voicemail and call diversions. Optus’s troubleshooting page says to check there.
Things that trip people up
And what Optus says to do about each one.
- Your phone never rings. Optus’s likely culprit is an all-calls divert (code 21). Dial ##21#, then set the divert you wanted.
- Callers get Optus’s Missed Call Service. Dial 159 and follow the prompts to switch it off, then set your divert again.
- Callers hear “this number is not listed”. The divert is going to a voicemail box that isn’t switched on. Dial 1509 to turn voicemail on, or use the My Optus app on prepaid.
- Callers get a disconnected tone. The number in the divert may be wrong, so Optus says to cancel it and set it up again.
- The code does nothing. Optus points you to your phone maker’s guide, or use the My Optus app.
- Your iPhone silences unknown callers. Optus’s iPhone guide says those calls go to voicemail and show as missed. New customers ring from unknown numbers, so test with one.
Getting voicemail back
Want missed calls back on Optus voicemail? Optus’s ring time page gives **61*321**20# for calls you don’t answer within 20 seconds. Its iPhone guide adds **67*+61411000321# for when you’re on a call and **62*+61411000321# for no coverage.
In the My Optus app, it’s Settings, Voicemail and call diversions, pick when, then Voicemail. Optus says voicemail changes there take 15 minutes to 4 hours, so test it after that.
On a Samsung or an iPhone
Samsung Galaxy: Optus’s Galaxy S26 guide uses the menus. In the Phone app, tap the menu icon, then Settings, Supplementary services and Call forwarding. Pick the type of divert, type in the number and tap Enable. To stop it, pick it again and tap Disable.
iPhone: Optus’s guide uses the codes above, typed into the Keypad. Our forwarding help page, linked below, covers the iPhone’s own Call Forwarding setting and Live Voicemail.
What a divert costs on Optus
Optus doesn’t charge for the call coming in, only for the second leg, from your phone to wherever the call goes.
| The forwarded part of the call | |
|---|---|
| Postpaid mobile | Your plan’s rates for local, national and mobile numbers, so check what your plan includes |
| Prepaid mobile | 10c a minute to local, national and mobile numbers |
| Home phone and other fixed lines | Your fixed line plan’s rates |
From Optus’s “Call diversions costs” page, read 12 October 2026. Optus says diversions switched on at the exchange, rather than from your phone, may cost differently.
Home phones, office phones and Optus Loop
Landlines and business phone systems have their own codes and menus.
| How to set it | |
|---|---|
| Home phone | Dial *78, then the number, and wait for two short beeps. #78 turns it off. Optus says this is for eligible services |
| Office phone, 1 to 5 staff | Call Divert has to be switched on for the line first, which Optus says can take up to 48 hours. Its link for doing that online didn’t load when we checked, so ask Optus. Then dial *78 and the number, and wait for two short beeps. #78 turns it off |
| Office phone on Directline, 6 to 300 staff | *91, the number, then # for every call. *92 instead for when it’s busy, *93 for no answer. #91#, #92# or #93# turns each one off |
| Office phone on Multiline | Your PABX maintainer sets it up. If you can’t do it yourself, Optus says to ring 13 33 43 |
| Business mobile, 1 to 5 staff | In the My Optus app, tap the Menu icon, then Settings, then Setup call diversions |
| Business mobile, 6 to 300 staff | Optus asks you to send its mobile diversion request form |
| Optus Loop with RingCentral | In the RingCentral app, tap your profile picture, then Call rules, turn on Forward all calls and choose Forward the call. You need call handling permission |
From Optus’s help page for each, read 12 October 2026. Optus says Loop may need new codes since its move to RingCentral, so use the app for Loop.
Where to send missed calls
A divert only moves the call. Whatever’s at the other end still has to answer it.
An AI receptionist can answer it instead, and we sell one. Ours answers as your business, says it’s your assistant, gets the job details and texts you anything urgent. You keep your Optus number. With the 004 code your phone rings first, and with code 21 our assistant takes every call. We set it up with you on a call.
Optus call forwarding questions
How do I turn off call forwarding on Optus?
Dial ##002# and press call to cancel every divert. To remove just one, dial ## then its code then #, like ##21#. You can also remove them in the My Optus app, under Voicemail and call diversions.
How do I activate call forwarding on my Optus mobile?
Dial **004*, then the number, then **20#, and press call. Your phone rings for 20 seconds, then diverts the calls you don’t take. For every call with no ringing, dial **21*, the number, then #.
How do I check if call forwarding is on with Optus?
Look in the My Optus app, under Settings, then Voicemail and call diversions. Optus’s troubleshooting page sends you there too, and warns that an all-calls divert stops calls reaching your phone at all.
Does Optus charge for call diversions?
Not for the call coming in. The forwarded leg is charged at your plan’s rates on postpaid, and 10c a minute on prepaid, to local, national and mobile numbers.
How do I forward my Optus landline to a mobile?
On an Optus home phone, dial *78, then the mobile number, and wait for two short beeps. #78 stops it. An office phone needs Call Divert switched on for the line first.
How long does an Optus mobile ring before it diverts?
As long as you set, from 5 to 30 seconds in steps of 5. It’s the two numbers before the last #, so **20# means 20 seconds. Optus says that’s about 4 to 8 rings.
Keep reading
- Forwarding codes for Telstra, Optus and Vodafone, plus iPhone and Samsung settings
- Missed-call text back: a text from your business name when you can’t pick up
- Ringing you first, or answering every call
- Voicemail or an AI receptionist
- How our AI receptionist handles a call
- Vodafone call forwarding, code by code
- Call forwarding on iPhone and Android phones
- Can your iPhone or Android answer calls for you with AI?
- Auto-reply to missed calls on your own phone
- Voicemail greetings for tradies
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