Have you ever missed an important call because your phone was in a dead zone, buried in a bag, or simply out of battery? Call forwarding is the quiet feature that solves that problem, and most people never touch it until the day they desperately need it. The good news is that setting it up takes less than a minute once you know which method matches your phone and carrier. The bad news is that the wrong method can leave you with silent, missing calls and no idea why.
This guide walks through the practical ways to forward calls on mobile phones, landlines, and office systems, plus the mistakes that trip people up and the fixes that actually work.
What call forwarding actually does
Call forwarding is a telephone-network feature that redirects incoming calls from one number to another. The redirect happens on the network side, not on your handset, which is why it still works when your phone is off, has no signal, or is sitting in a drawer.
There are two broad flavors, and confusing them is the most common mistake:
- Unconditional forwarding sends every call to the second number immediately. Your phone never rings.
- Conditional forwarding only kicks in under specific conditions: when you are already on a call (busy), when you do not pick up within a set time (no answer), or when your phone is switched off or out of coverage (unreachable).
That distinction matters because conditional forwarding is usually what people actually want. Unconditional forwarding sounds helpful until you realize you have accidentally sent every call to voicemail and stopped answering your phone entirely.
How to forward calls on Android
Android does not have one universal forwarding screen. The setting lives in the Phone app and depends on both your carrier and your phone manufacturer, so the menu path varies.
The most reliable route is the carrier feature code, which works on almost any Android phone regardless of brand:
- Open the Phone app and bring up the keypad.
- Dial the activation code for the forwarding type you want (see the table below).
- Press the call button and wait for a confirmation message or tone.
- To turn it off, dial the matching deactivation code.
If you prefer menus, open the Phone app, tap the three-dot menu, then Settings, then Calls, then Call forwarding. You will see separate options for always forward, forward when busy, forward when unanswered, and forward when unreachable. Enter the target number and save.
One practical tip: if the Call forwarding menu is greyed out or missing, your carrier has disabled it at the account level. No amount of tapping will fix that. You will need to call support or use the carrier’s app. If you are also fighting unwanted calls, it helps to sort out spam blocking first with this guide to block spam calls on Android, because forwarding and blocking settings can interact in confusing ways.
How to forward calls on iPhone
On iPhone, the setting is refreshingly consistent. Go to Settings, then Phone, then Call forwarding, toggle it on, and type the number. That covers unconditional forwarding only.
For conditional forwarding on iPhone, you generally have to use carrier feature codes on the keypad, because iOS does not expose busy, no-answer, and unreachable options in the Settings app. This is a genuine gap, and it catches out a lot of people who assume the iPhone menu covers everything.
If your iPhone shows the Call forwarding toggle but it will not stay on, the usual culprits are a carrier account restriction, a missing SIM update, or a conflicting setting in the carrier’s own app. Restarting the phone and re-seating the SIM resolves a surprising number of these cases. For a deeper walkthrough of the settings that genuinely work, see this guide on blocking spam calls on iPhone, which covers the Phone settings menu in detail.
The feature codes you need
These GSM-style codes follow a consistent pattern: an asterisk, a service code, an asterisk, the target number, and a hash, then the call button. Deactivation swaps the asterisks for hashes and drops the number.
| What it does | Activate | Deactivate |
|---|---|---|
| Forward all calls | `21number#` | `##21#` |
| Forward when busy | `67number#` | `##67#` |
| Forward when no answer | `61number#` | `##61#` |
| Forward when unreachable | `62number#` | `##62#` |
| Cancel all forwarding | — | `##002#` |
Two warnings worth taking seriously. First, these codes are widely used but not perfectly universal; some networks use variations, and VoIP services ignore them entirely. Second, `##002#` is your emergency brake. It cancels every forwarding rule at once, which is exactly what you want when calls are vanishing and you cannot work out why.
Forwarding on landlines and office systems
Traditional landlines use star codes that vary by region and provider, so the only reliable source is your carrier’s own documentation. In North America, for example, the codes differ from the European GSM set above.
VoIP and PBX systems are a different world. Platforms like Asterisk, Cisco call managers, and Microsoft Teams implement forwarding through their own configuration screens or dial plans rather than carrier codes. In a business phone system, forwarding is usually set per extension, and administrators can apply rules that route calls by time of day, caller, or department. If you are setting this up at work and the codes do nothing, you are almost certainly on a system that expects configuration through an admin portal instead.
Common mistakes and how to fix them
Most forwarding problems come down to a handful of repeatable errors. Here is what actually goes wrong in practice.
Forgetting which rule is active. People set unconditional forwarding for a holiday, come back, and wonder why their phone never rings for three weeks. Dial `##002#` to clear everything, then set only the rules you need.
Forwarding to a number that also forwards. If number A forwards to B and B forwards back to A, calls can loop or drop entirely. Some networks detect this and reject the setup; others let you create the mess silently.
Assuming forwarding covers texts. Standard call forwarding does not redirect SMS. Message forwarding is a separate feature, and on many carriers it is not available at all. If you are switching phones and want your messages to follow you, that is a different task entirely, closer to something like forwarding Gmail to another address than to call routing.
Ignoring the billing angle. Forwarded calls are often billed as outgoing calls from your line, and forwarding to international numbers can carry steep per-minute charges or be blocked outright. Check your plan before forwarding abroad.
Skipping authentication. Because forwarding can be abused for toll fraud, many carriers require account verification before changes take effect. If a code fails repeatedly, this is often why.
Testing badly. Always place a test call from a different phone after changing settings. Testing from the same handset proves nothing, since the call never leaves your line.
Forwarding when your connection is the problem
Sometimes the real issue is not forwarding at all. If calls drop mid-conversation or audio cuts out, the problem may be your network or your Wi-Fi, and forwarding will just move the bad experience to another device.
On home networks, prioritising the devices that matter makes a measurable difference to call quality. This guide on how to prioritize devices on your Wi-Fi for smoother video calls and gaming explains the quality-of-service settings involved. For people who take a lot of calls on the move, the headset matters as much as the network, and this roundup of the best earbuds for phone calls and meetings covers what to look for in microphone quality. (ITU Telecommunication Standardization Sector (ITU-T) overview)
When to use forwarding, and when not to
Forwarding is the right tool when you are temporarily away from a number, when you are migrating between carriers and want calls to keep arriving, or when a business needs after-hours calls to reach an on-call phone. It is the wrong tool when you simply want voicemail, when you want texts redirected, or when you are trying to dodge spam, since forwarding a spam call just moves it somewhere else.
A quick decision guide:
- Going on holiday and want calls on a second phone? Conditional forwarding on no answer.
- Phone broken, waiting for a replacement? Unconditional forwarding to a working number.
- Office line that should ring a mobile after 6pm? PBX time-based rule, not a carrier code.
- Calls mysteriously not arriving? Dial `##002#` and start again.
Conclusion
Call forwarding is one of those features that rewards five minutes of attention. Learn the four conditional codes, know where the menu lives on your specific phone, and remember that `##002#` clears everything when calls go missing. Test with a real call from another device, check your plan for forwarding charges before sending calls abroad, and do not expect texts to follow your calls. Get those basics right and forwarding becomes a genuinely useful safety net rather than a source of silent, unexplained missed calls.
Frequently Asked Questions
Does call forwarding cost money?
Often yes, at least for some types. Conditional forwarding within your own carrier is frequently included in plans, while unconditional forwarding and forwarding to international numbers are commonly billed per minute. Rates vary widely by carrier and country, so check your plan details before relying on it.
How do I cancel call forwarding?
Dial `##002#` and press call. This cancels all forwarding rules at once on most GSM-based networks. You can also cancel individual rules with their specific deactivation codes, or toggle the setting off in your phone’s Call forwarding menu.
Why is my Call forwarding option greyed out?
The setting is usually greyed out because your carrier has not enabled the feature on your account, or because your SIM provisioning is out of date. Restarting the phone or re-seating the SIM sometimes fixes it. Otherwise, contact your carrier to confirm forwarding is active on your line.
Does call forwarding also forward text messages?
No. Standard call forwarding applies to voice calls only. Text message forwarding is a separate service that many carriers do not offer at all, and where it exists it is configured differently from call forwarding.
Can I forward calls to a different country?
Sometimes, but expect restrictions. Many carriers block or surcharge international forwarding to prevent fraud, and some require account authentication before the change will stick. Confirm the per-minute rate with your carrier first, because international forwarding charges can add up quickly.
What happens if I forward calls to a number that is switched off?
The call will typically go to that number’s voicemail or fail entirely, depending on the network. It will not bounce back to your original phone. This is why testing with a real call from another device matters before you rely on forwarding for anything important.
One last practical note on timing: forwarding rules can take a minute or two to propagate across the network, so a test call placed immediately after dialling a code may still ring the original handset. Wait a couple of minutes, then test again before concluding the setup failed. If you manage several lines, keep a short written record of which rules are active on each number and when they were set; this small habit prevents the classic holiday-forwarding fiasco. Finally, revisit your rules whenever you change plans or carriers, since migrations can silently reset or drop forwarding configuration. With those habits in place, call forwarding stays a reliable tool you control rather than a mystery you inherit.
