Setup guide
How to Forward Only Missed Calls (and Why It Can Fail Without Warning)
To forward only the calls you don't answer, use conditional call forwarding: dial *71 plus the number on Verizon, or **61*1 plus the number and # on T-Mobile. AT&T publishes no code for it on cell phones, and an iPhone's settings can only forward every call. Whatever you set up, test it from a second phone, because a conditional code that didn't take sounds exactly like one that did.
By CompleteLine · Published October 24, 2026 · Codes checked against each carrier's own support page that day
Two kinds of call forwarding
Forward all calls (also called unconditional or immediate forwarding) sends every call to another number. Your own phone doesn't ring while it's on.
Forward missed calls (conditional, "no answer/busy transfer") lets your phone ring first and sends the call on only if you don't pick up, are on another call, or your phone is off. It's what most owners picture when they want missed calls to go to an answering service or a second phone.
The codes, carrier by carrier
Dial these from the phone whose calls you want forwarded, then press call.
Verizon
Missed calls only: *71 + the 10-digit number (forwards when you’re busy or don’t answer)
All calls: *72 + the 10-digit number
Turn off: *73
Source: Verizon support
T-Mobile
Missed calls only: **61*1 + the 10-digit number + # (forwards when you don’t answer). Change the delay from 5 to 30 seconds by adding **seconds before the #.
All calls: **21*1 + the 10-digit number + #
Turn off: ##61# turns off no-answer forwarding; ##21# turns off forward-all
Source: T-Mobile support
AT&T (wireless)
Missed calls only: AT&T publishes no code for forwarding only unanswered calls on a cell phone. Ask AT&T directly.
All calls: Your phone’s Call Forwarding setting (AT&T’s support pages point to the device tutorials)
Turn off: The same setting, switched off
Source: AT&T support
iPhone (any carrier)
Missed calls only: Not in Settings. Apple says to contact your carrier for conditional forwarding.
All calls: Settings → Apps → Phone → Call Forwarding
Turn off: The same switch, turned off
Source: iPhone support
Business landlines and VoIP systems (RingCentral, Google Voice, a desk-phone system) set forwarding in their own admin settings, not with these codes.
Why conditional forwarding can fail without warning
After you dial a forwarding code, the phone plays a confirmation tone or shows a short message. That tells you the phone sent the code. It doesn't tell you unanswered calls will actually be forwarded. That depends on your carrier supporting it on your plan and phone, and only two of the four big options above publish a code for it at all.
The problem is that nothing tells you. Answered calls work normally, so everything looks fine. The calls that disappear are the ones you never saw, which is exactly where you can't notice. Owners often find out weeks later, when a customer mentions they called twice and nobody got back to them.
How to test it in two minutes
- Turn it on. Dial your carrier's code with the destination number.
- Call from a second phone and don't answer. Let it ring out.
- Check the destination. The call should arrive there. If it goes to your voicemail instead, forwarding isn't working.
- Test with your phone off, and again while you're on another call.
- Re-test after any change to your phone, plan or carrier.
Why CompleteLine forwards every call instead
CompleteLine uses forward-all, not conditional forwarding. Forward-all is documented on every carrier and every phone, so it can't quietly stop working. When it's off, you notice right away, because your phone rings again.
The tradeoff, said plainly: while forwarding is on, your own phone doesn't ring. Every call reaches CompleteLine, which texts the caller back in about 5 seconds and answers their questions by text. On Pro, an AI receptionist (which says it's an AI) answers the call. That suits an owner who is on a roof or under a sink all day. It doesn't suit a shop where someone at the front desk answers most calls; for that, conditional forwarding to a second line, tested as above, is the better fit.
Setup is one code (*72 on Verizon), and one code turns it back off (*73). You keep your number and your carrier. More on how missed call text back works, and how it compares to an answering service.
Questions
What is the code to forward only unanswered calls?
On Verizon, dial *71 and the 10-digit number. On T-Mobile, dial **61*1, the 10-digit number, then #. AT&T publishes no such code for cell phones, and the iPhone’s Settings app only forwards every call; Apple says to ask your carrier for conditional forwarding.
How do I turn call forwarding off?
On Verizon, dial *73. On T-Mobile, dial ##61# for no-answer forwarding or ##21# for forward-all. On an iPhone or with AT&T, switch off Call Forwarding in the phone’s settings.
How do I know conditional forwarding actually worked?
Test it. Call your business number from a second phone, let it ring out without answering, and check that the call reaches the forwarding number. Then test again with your phone switched off. The confirmation tone you hear after dialing the code doesn’t prove anything on its own.
Can I keep my business number?
Yes. Forwarding doesn’t move your number. You keep the same number and the same carrier, and you can turn forwarding off any time with your carrier’s off code.
Does CompleteLine use conditional forwarding?
No. CompleteLine uses forward-all (*72 on Verizon), because it works the same on every carrier and can’t quietly stop working. The tradeoff is that your own phone stops ringing while forwarding is on: every call reaches CompleteLine, which texts the caller back in about 5 seconds, or, on Pro, has an AI receptionist answer. One code turns it off.
See what a caller gets
Try the live demo to see the text a caller receives. Core is $249/mo plus a one-time $500 setup, month to month, with a 30-day money-back guarantee.