Missing a call can mean missing a new client, an urgent appointment, or an important update. Call forwarding lets you redirect incoming calls to another number, so someone (or something) always picks up. Whether you want calls routed to a colleague, a second phone, or an AI phone assistant like Safina, the setup takes just a few minutes.
This guide covers every method: built-in phone settings, universal GSM codes, and carrier-specific instructions.
What Is Call Forwarding?
Call forwarding sends your incoming calls to a different phone number. You can forward all calls unconditionally, or set conditions: only when you don’t answer, when your line is busy, or when your phone is unreachable (turned off, no signal, airplane mode).
Most people use conditional forwarding. That way, you still receive calls normally, but if you can’t pick up, the call goes somewhere useful instead of dying in a generic voicemail box.
Call Forwarding on iPhone (iOS)
Apple makes this straightforward through the Settings app.
Steps
- Open Settings > Phone > Call Forwarding
- Toggle Call Forwarding on
- Enter the phone number you want calls forwarded to
- Tap Back to save
That’s it. A small phone icon appears in your status bar when forwarding is active.
Important Notes for iPhone
- This enables unconditional forwarding, meaning every call goes to the new number. Your phone won’t ring at all.
- If you only want to forward unanswered or busy calls, use the GSM codes described below instead.
- On some carriers, the Call Forwarding toggle may be grayed out. This usually means your carrier doesn’t support the feature through the settings UI, or you need to contact them to enable it. You can still use GSM codes as a workaround.
Call Forwarding on Android
Android varies by manufacturer, but the general path is similar across Samsung, Google Pixel, OnePlus, and other devices.
Steps
- Open the Phone app
- Tap the three-dot menu (top right) > Settings
- Select Calling accounts or Supplementary services (varies by device)
- Tap Call forwarding
- Choose your forwarding type:
- Always forward (unconditional)
- Forward when busy
- Forward when unanswered
- Forward when unreachable
- Enter the destination number and confirm
Samsung-Specific Path
On Samsung Galaxy phones: Phone app > Menu > Settings > Supplementary services > Call forwarding > Voice call.
Google Pixel Path
On Pixel devices: Phone app > Settings > Calling accounts > select your SIM > Call forwarding.
Universal GSM Codes (Works on Any Phone)
GSM codes work on virtually every phone and carrier. You dial them like a regular phone number. This is the most reliable method, and it’s the one we recommend.
Open your phone’s dialer and enter these codes, replacing [number] with the full destination number (including country code, like +491701234567).
Forward All Calls (Unconditional)
Activate: **21*[number]#
Deactivate: ##21#
Check: *#21#Forward When No Answer
Activate: **61*[number]**[seconds]#
Deactivate: ##61#
Check: *#61#Replace [seconds] with how long your phone should ring before forwarding: 5, 10, 15, 20, 25, or 30 seconds. Most people use 15 or 20.
Forward When Busy
Activate: **67*[number]#
Deactivate: ##67#
Check: *#67#Forward When Unreachable
Activate: **62*[number]#
Deactivate: ##62#
Check: *#62#Cancel All Forwarding
##002#This one code removes every forwarding rule at once. Useful when you want a clean slate.
Quick Example
Say you want unanswered calls (after 20 seconds of ringing) forwarded to +491701234567:
**61*+491701234567**20#Dial that code, press call, and you’ll see a confirmation message. Done.
Carrier-Specific Instructions
T-Mobile / Magenta
T-Mobile supports all standard GSM codes. You can also manage forwarding through the T-Mobile app or your online account at my.t-mobile.com. For customer support, dial 611 from your T-Mobile phone.
AT&T
AT&T uses GSM codes on its network. Unconditional forwarding can also be set up by dialing *72 followed by the number, and deactivated with *73. For conditional forwarding, use the standard GSM codes above.
Verizon
Verizon supports *72 / *73 for unconditional forwarding. For conditional forwarding (busy, no answer, unreachable), use the GSM codes. You can also manage settings through the My Verizon app.
Other US Carriers
Most US carriers support standard GSM codes. If your carrier uses a CDMA-only network (increasingly rare), you may need to contact them directly or use their app.
European Carriers
Telekom, Vodafone, O2 (Germany): Standard GSM codes work. Forwarding is included in all plans. Some business plans offer additional forwarding options through carrier portals.
Swisscom, Sunrise, Salt (Switzerland): Same GSM codes. Forwarding costs may apply on older prepaid plans, so check your terms if you are on prepaid.
A1, Magenta, Drei (Austria): Standard codes work. A1 offers a dedicated forwarding management page in their app.
Landlines and VoIP
Landlines and VoIP phones do not use GSM codes. Instead, forwarding is configured through your router’s web interface (FRITZ!Box users: go to Telephony > Call Handling) or your VoIP provider’s dashboard. The concept is the same, but the setup steps differ.
Business PBX Systems
If your office uses a phone system with extensions, forwarding rules are set in the PBX admin panel. Your IT team can configure individual extensions to forward to another number, or set up a hunt group that tries internal extensions first and forwards as a last resort.
Not sure about your number format? Use our phone number validator to check that the destination number is correct before setting up forwarding.
Forwarding to Voicemail vs. a Real Destination
Most phones come with calls forwarded to your carrier’s voicemail by default. That’s fine if you actually check your voicemail. But let’s be honest: most people don’t. Messages sit there for days, and callers often hang up before leaving one anyway.
A better option is forwarding to a number where someone (or something) actually answers, asks the caller what they need, and sends you a summary. That’s exactly what services like Safina do. But more on that at the end.
If you just need a better voicemail greeting, our voicemail script generator can help you create a professional message in seconds.
Does Call Forwarding Cost Money?
This depends on your plan, but for most modern mobile plans, forwarding is free or close to free.
Forwarded calls count as an outgoing call from your number to the destination number. If both numbers are domestic and your plan includes unlimited calls (or a large minute allowance), there is no extra charge.
Situations where costs might apply:
- Prepaid plans with per-minute billing: each forwarded call costs whatever your outgoing rate is
- International forwarding: if you forward to a number in a different country, international rates apply
- Some legacy landline plans may charge per forwarded call
For most users on standard postpaid mobile plans, call forwarding adds nothing to your regular phone bill.
Troubleshooting Common Issues
”Call Forwarding Failed” or No Confirmation
- Double-check the destination number, including country code
- Make sure you have cellular signal (GSM codes don’t work over Wi-Fi)
- Try removing the
+and using the full international format (e.g., 00491701234567 instead of +491701234567) - Some carriers require you to enable call forwarding on your plan first. Call your carrier’s support line to check.
Calls Still Going to Voicemail
- You may have carrier-level voicemail forwarding active alongside your custom forwarding. Dial
##004#to clear conditional forwarding, then set up your new rules. - On iPhone, turn off Visual Voicemail if it conflicts with your forwarding destination.
Forwarding Works, but the Destination Doesn’t Ring
- Confirm the destination phone is on and has signal
- Check that the destination number doesn’t have its own call forwarding or blocking enabled
- If forwarding to a VoIP number or service, make sure it accepts calls from your carrier
GSM Codes Don’t Work
- Your carrier might not support the code. Contact their support.
- On dual-SIM phones, make sure you’re dialing the code from the correct SIM.
- Some VoIP-based carriers (like Google Fi) handle forwarding differently. Check their support docs.
Forwarding Activates but Calls Still Ring on Your Phone
This is normal for conditional forwarding (busy, no answer, unreachable). Your phone rings first, and only forwards if the condition is met. If you want calls to skip your phone entirely, use unconditional forwarding (**21*[number]#).
Which Forwarding Type Should You Use?
| Scenario | Forwarding Type | GSM Code |
|---|---|---|
| Never miss a call, even when busy | All conditional (no answer + busy + unreachable) | Set up all three: **61*, **67*, **62* |
| Going on vacation | Unconditional | **21*[number]# |
| Phone often dies or loses signal | Unreachable only | **62*[number]# |
| In meetings and can’t answer | No answer (with short ring time) | **61*[number]**10# |
The Best Combination for Most People
If you want to catch every missed call without giving up the ability to answer your phone yourself, activate all three conditional types together: no answer + busy + unreachable. This means:
- If you are available and answer, nothing changes
- If you do not answer within your set ring time, the call forwards
- If you are on another call, the second call forwards instead of getting a busy signal
- If your phone is off or out of range, the call still gets answered
You stay in control during hours when you want to take calls, and your forwarding destination covers everything else.
Call Forwarding FAQ
“Can callers tell their call was forwarded?” No. The forwarding happens transparently. From the caller’s perspective, they dialed your number and someone answered. They do not see or hear any indication of forwarding.
“Can I forward only during certain hours?” With conditional forwarding (no-answer, busy, unreachable), you control this by answering or not answering your phone. Some business phone systems also support time-based forwarding rules that activate automatically by schedule.
“Does forwarding work with dual SIM phones?” Yes, but forwarding settings are per SIM. Configure forwarding on the SIM that receives your business calls.
Forward Your Calls to an AI Assistant
If you’re a freelancer, consultant, or small business owner, forwarding unanswered calls to Safina is a practical option. Safina is an AI phone assistant that picks up when you can’t, asks callers what they need, and sends you a summary with action items.
Setup takes about five minutes: you get a dedicated Safina number, then use the GSM codes above to forward unanswered calls to it. Your phone rings first, and if you don’t pick up, Safina handles the conversation. No hardware, no apps running in the background, no extra phone needed.
It’s made in Germany, GDPR-compliant, and plans start at $11.99/month for 30 minutes. You can learn more on our call forwarding solutions page.