Forward Business Calls to an AI Receptionist (2026)
You signed up for an AI receptionist, it gave you a phone number, and now you are looking at the phone in your pocket wondering what you are actually supposed to do with it. Nobody wants to reprint the van, the cards and the Google listing with a new number. So you go looking for how to point your existing line at the new one, and you find a dozen pages of star codes copied from each other, most of which teach you the wrong setting.
This is a guide to doing it properly. NoMissedCall is our product, so we have an obvious interest in you setting up an AI receptionist successfully — read it with that in mind. Everything below links to a carrier's own support page, Apple's own documentation, or the telecoms standard that defines the codes, rather than to another vendor's blog. Where a carrier does not publish something, we say so instead of inventing it.
There are two kinds of forwarding, and most guides only teach one
Every guide you have read hands you *72 and moves on. That is unconditional forwarding: every call to your number goes straight to the other line, immediately, and your own handset never rings at all. It is the right setting if you have genuinely stopped answering your business phone.
Almost nobody has. What a plumber or a salon owner actually wants is conditional forwarding: your phone rings first, and the call only bounces to the AI if you didn't answer it, or you were already on another call, or your phone was off. You keep every call you want and the AI catches the rest.
The distinction is not a vendor invention — it is baked into the mobile standard. 3GPP TS 22.030, the specification that defines the codes your dialler sends, lists four separate forwarding services with four separate service codes: unconditional (21), on busy (67), on no reply (61), and when not reachable (62). It also defines two bulk codes: 002 for all forwarding, and 004 for all conditional forwarding — the three conditional ones together, which is usually exactly what you want to set in one go.
The generic pattern from that same specification is worth memorising, because it works on any GSM network and it explains every code in this article:
- Register a destination: **SC*number#
- Deactivate without forgetting the destination: #SC*number#
- Check what's set: *#SC#
- Erase completely: ##SC#
So **004*5551234567# sends every unanswered, busy and unreachable call to that number, and ##002# wipes all forwarding of every kind. Dial them exactly as written, press the call button, and wait for the network's confirmation message.
What the three big carriers actually publish
This is where most guides quietly stop being accurate. Only one of the three major US carriers publishes a star-code table for wireless at all.
| Carrier | What it publishes | Codes |
|---|---|---|
| Verizon | A full call forwarding FAQ with codes | *72 + 10-digit number to forward everything; *73 to turn it off; *71 + 10-digit number to forward only the calls you don't answer |
| AT&T | Behaviour and billing, but no wireless code table — it points you at per-device tutorials | None published for wireless; use the standard codes above. AT&T does publish *72 for its traditional business landline |
| T-Mobile | The rules and the conditions, but no code table — also points you at per-device tutorials | None published; use the standard codes above |
Verizon's *71 is the single most useful code in this article and the one nearly every listicle omits. Verizon describes it in one line: it forwards "only the calls you don't answer on your mobile phone." That is conditional forwarding, published by the carrier, on a page you can send to a sceptical business partner.
For AT&T and T-Mobile, the absence of a published table is not a dead end. Both run GSM networks, and the standard codes above are what your phone's own settings screen sends anyway. T-Mobile's calling services page confirms the capability exists in the words a standard would use — you can forward "if you don't answer the call, if your phone is turned off, or if you're out of signal range" — it simply routes you to a per-device tutorial for the steps rather than printing the codes.
Why the switch in your iPhone settings is the wrong tool
There is a Call Forwarding toggle at Settings › Apps › Phone on an iPhone, and it is tempting because it is a switch rather than a string of asterisks. It is also unconditional only. Apple's own iPhone User Guide is unusually direct about the limit: "If your carrier supports conditional call forwarding when the line is busy or not in service, contact them for setup information." Apple does not build a UI for it. Flip that switch and your phone stops ringing entirely.
Two more things from the same Apple page that catch people out. Call forwarding on iPhone requires a GSM network — on CDMA, Apple tells you to contact your carrier. And you "must be in range of the cellular network when you set iPhone to forward calls, or calls won't be forwarded," which is why setting this up in a basement or a rural blackspot silently does nothing.
Android is better here. Most builds of the Phone app expose all four conditions separately under call settings — usually labelled something like "Always forward," "Forward when busy," "Forward when unanswered" and "Forward when unreachable." Set the last three, leave the first one off, and you have conditional forwarding without dialling a code. The menu path moves between manufacturers and Android versions, so if you cannot find it, the dial codes work identically on any Android handset.
The Google Voice trap
If the number on your van is a Google Voice number, stop before you set anything up. Google's own help documentation on linked numbers states it in a single sentence: "Forwarding calls from your Google Voice number to an automated system is unsupported."
That is not a warning that it will definitely fail. It is a warning that when it does — and the usual symptom is calls dropping or landing in Google's own voicemail instead of reaching the AI — Google will not troubleshoot it with you, because you are outside what the product supports. Google Voice is designed to ring your phones, not to hand calls off to another automated service.
Two honest options if that is your situation: publish the AI receptionist's number directly on your listings and website and let Google Voice keep doing whatever it does today, or port the number to a carrier whose forwarding is supported. There is no clever code that makes the unsupported path supported.
Five things that quietly break
1. Your voicemail stops working. AT&T states it flatly: "Call forwarding overrides your wireless voicemail." This is the intended outcome — the AI is meant to replace voicemail — but it surprises people who assumed both would run. If you forward unconditionally, you also stop getting missed-call notifications on your own phone, so the app's call log becomes your only record.
2. Forwarded calls can cost you minutes. Verizon's FAQ: if you don't have unlimited minutes, "you'll be billed for all forwarded calls according to your plan… even if the calls are forwarded to a landline." AT&T's page says the same thing in different words — forwarded calls "are billed for the length of the call" and may incur long distance or roaming charges. On the unlimited plan most business lines run today this is academic. On a legacy metered plan it is a real line item, and it is the one thing in this article worth checking your bill for.
3. International destinations are blocked. AT&T: "You can't forward calls to an international number." T-Mobile: "You can't forward calls to international numbers. You can only forward calls to 10- or 11-digit numbers." If the number your AI receptionist issued you is a US number this never comes up — but it is why forwarding sometimes refuses to register with no useful error.
4. A busy destination gives your caller a busy signal. AT&T warns that "if the designated forwarding number is busy, callers to your number will receive a busy signal." This is the argument for choosing an AI receptionist that handles several calls at once rather than one that queues them. It is worth asking a vendor directly, because a single-channel destination turns a busy afternoon into a wall of busy tones.
5. Chained forwarding. If your published number already forwards somewhere — an old answering service, a second handset, a virtual number you set up years ago and forgot — adding another hop on top produces behaviour that is very hard to reason about. Dial *#004# and *#21# before you change anything, and wipe with ##002# if the answers surprise you.
Getting the ring order right
Once conditional forwarding is on, one number decides whether the whole setup feels good or annoying: how long your phone rings before the call moves on. 3GPP TS 22.030 defines a "No Reply Condition Timer" of 5 to 30 seconds, and you can set it explicitly by appending the seconds to the registration code — **61*5551234567**20# registers a no-answer forward with a 20-second timer.
Twenty seconds is roughly four or five rings. Shorter and you will never get to the phone in time on a job site. Longer and a caller who is already dialling three plumbers has moved on to the second one. If in doubt, start at 20 and adjust after a week of watching your own call log.
A useful thing to know before you spend an evening tuning timers: some AI receptionists implement the ring-first behaviour inside the product rather than at the carrier. NoMissedCall's is called ring-first screening — your phone rings, you press 1 to take the call yourself, or stay silent and the AI picks it up seamlessly, and a call you answer that way uses none of your AI minutes. The Help Center covers the setup and the carrier codes for your specific line.
Where forwarding is the wrong answer entirely
Forwarding is a workaround. It exists because moving a phone number is a hassle, not because bouncing calls between two networks is elegant. Three situations where something else is better.
Port the number instead. If you are willing to move your business number to the service that answers it, every problem in this article disappears — no chained hops, no billing surprises, no carrier-specific codes, no basement-with-no-signal failure mode. It takes longer to set up and it is harder to reverse, which is why most people forward first and port later, if at all.
You need a phone system, not an answering layer. If you have staff, extensions, a shared inbox and a queue, a business phone platform that includes AI answering is a better fit than a receptionist product bolted onto a personal mobile line. That is a genuinely different category with genuinely different pricing, and we wrote about how the categories compare in our breakdown of what 200 minutes actually costs.
Where our competitors do this better. Nothing in this guide is proprietary — the codes are a public standard, and forwarding to Rosie, Clara (heyitsclara.com) or a human answering service works identically. On the specifics, Rosie's published entry plan gives you 250 minutes for $49 a month as of August 2026, which sits exactly on our own Pro allowance, and its warm and live transfer features are a real advantage if you want the AI to hand a live caller to a person rather than take a message. Clara advertises unlimited calls answered on a flat monthly fee, which removes minute anxiety in a way a minutes-based plan simply cannot — if your call volume is genuinely unpredictable, that is a better shape of pricing than ours, and we would rather say so than pretend otherwise. Our roundup of AI receptionist apps you can run from your phone goes through the trade-offs in more detail.
The five-minute version
If you skipped to the end: dial *#004# to see what forwarding is already set on your line. Dial ##002# to wipe it. Then dial **004* followed by your AI receptionist's number and # to send every unanswered, busy and out-of-coverage call to it, while your own phone keeps ringing first. On Verizon, *71 plus the 10-digit number does the no-answer case on its own. Make a test call from a different phone, let it ring out, and confirm the AI picked up and the transcript landed in your app.
Then leave it alone for a fortnight and read your call log. The calls you never knew about are the entire reason to do any of this — and if you want to know who else is dialling your number now, our piece on Google's AI calling businesses for pricing is worth ten minutes.
Frequently asked questions
What is the difference between conditional and unconditional call forwarding?
Unconditional forwarding sends every incoming call straight to the forwarding number — your own handset never rings. Conditional forwarding only redirects calls that meet a condition: you didn't answer, you were already on a call, or your phone was off or out of coverage. For an AI receptionist, conditional forwarding is almost always the one you want, because you keep the option of picking up yourself.
Will forwarding my calls to an AI receptionist break my voicemail?
Usually yes, and that's the point. AT&T's own support page states plainly that "call forwarding overrides your wireless voicemail." Once a call is forwarded, the forwarding destination decides what happens to it, so your carrier voicemail never gets a chance to pick up. If you set unconditional forwarding you will also stop seeing missed-call notifications on your own phone.
Do forwarded calls use my plan minutes?
On the two carriers that publish an answer, yes. Verizon's call forwarding FAQ says that if you don't have unlimited minutes, "you'll be billed for all forwarded calls according to your plan," and AT&T's page says forwarded calls "are billed for the length of the call." On an unlimited plan this is a non-issue, which is what most business lines are on now.
Can I forward a Google Voice number to an AI receptionist?
Google's own help documentation says that "forwarding calls from your Google Voice number to an automated system is unsupported." That doesn't guarantee it will fail, but it does mean Google will not help you when it does. If your published business number is a Google Voice number, the more reliable route is to publish the AI receptionist's number directly, or to move the number to a carrier that supports forwarding to automated systems.
How do I check what call forwarding is currently set on my phone?
Dial the interrogation code for the condition you want to check and press call: *#21# for unconditional forwarding, *#61# for no-answer forwarding, *#67# for busy, *#62# for unreachable, or *#004# for all conditional forwarding at once. The network replies with a status message. To clear everything and start again, dial ##002#.
How long does the phone ring before a no-answer forward kicks in?
The 3GPP standard that defines these codes allows a no-reply timer of 5 to 30 seconds, and you can set it yourself by appending the number of seconds to the registration code. Around 20 seconds — roughly four or five rings — is a sensible starting point: long enough that you can genuinely reach the phone, short enough that the caller doesn't give up first.
Try it on your own phone
No Missed Call is an AI receptionist that answers your business line 24/7, books appointments straight into your calendar, and sends you a transcript and summary of every call. Setup takes minutes from your phone, and there is a 7-day free trial.
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