Guides
Phone guides that answer the actual question
Step-by-step answers to the mechanical questions phones create: which code forwards a line, how to cancel it, why a mailbox never rings, and how to leave a message without placing a call.
Reviewed by Sujan ThapaliyaLast updated
What is in this section?
Guides covering call forwarding and voicemail: the carrier codes that turn forwarding on and off, what forwarded calls cost, how to configure voicemail on a VoIP line, and how to deliver a voicemail without ringing the handset. Each one cites the source its facts come from.
Start here
Which guide do I need?
| What is happening | Where to go |
|---|---|
| My calls are going somewhere else and I did not set that up | Call forwarding — the codes, and how to cancel them |
| I need calls to reach a colleague while I am away | Call forwarding, then the carrier guide for your network |
| My desk phone shows no message-waiting light | Voicemail on a VoIP phone |
| I want to leave a message without ringing the phone | Leave a voicemail without calling |
| Callers hang up before the mailbox answers | Voicemail — greetings and ring timing |
Call forwarding
Call forwarding guides
Verizon call forwarding: every code, and how to turn it off
On a Verizon wireless line, dial *72 followed by the 10-digit destination number to forward every incoming call, or *71 followed by the number to forward only the calls you do not answer. Dial *73 to turn forwarding off. Forwarded calls are billed as if you answered them.
All call forwarding guides
The full section, including the ones added since this page was written.
Voicemail
Voicemail guides
How to leave a voicemail without calling someone
There are four routes: call a number you know is switched off, use a carrier voicemail deposit number where one still exists, send a voice message through a messaging app, or use a voicemail drop through a calling platform. Only the last is reliable at volume, and it carries the same consent obligations as a call.
How to set up voicemail on a VoIP phone
On a VoIP line, voicemail lives in the phone platform rather than in the handset. Enable the mailbox on the extension or number in your provider's settings, set the PIN, record the greeting through the platform, turn on voicemail-to-email, then place a test call and leave yourself a message.
What to say in a business voicemail greeting (12 scripts)
A business voicemail greeting needs four things: who the caller reached, that the message was received, when someone will call back, and one route for anything urgent. Twelve to fifteen seconds is enough to say all four. Anything longer is answered by hanging up rather than by leaving a message.
All voicemail guides
The full section, including the ones added since this page was written.
Blocked and anonymous calls
Blocked, anonymous and restricted calls
What is a restricted call, and should you answer it?
A restricted call is one where the caller withheld their number, so your handset has nothing to display. It is not a special kind of call and it is not necessarily a scam — medical practices, switchboards, recruiters and government offices all withhold routinely — but you cannot tell which it is before answering.
No Caller ID: what it means and how to stop it
No Caller ID means the caller withheld their number, so the network passed the call with no identity to display. It is different from Unknown, which means the network had no number to pass. Both can be silenced on modern handsets, though doing so also blocks legitimate callers who withhold by default.
How to make an anonymous phone call
Dial *67 immediately before the number in North America, or 141 in the UK and much of Europe, and your caller ID is withheld for that call only. The recipient sees Private, Restricted or No Caller ID depending on their handset. Your number is still recorded by the carriers.
How to tell if someone has blocked your number
There is no definitive signal. The common pattern is one ring or none, then straight to voicemail, with messages that are never returned. But a phone that is off, on Do Not Disturb, or out of coverage produces almost the same behaviour, which is why a single call proves nothing.
How to block unwanted, restricted and spam calls
Blocking works in four layers: block individual numbers on the handset, silence unknown or withheld callers, enable carrier-level screening, and register on the national do-not-call list. No single layer stops everything, because most unwanted calling now presents a spoofed number that changes constantly.
All blocked and anonymous calls guides
The full section, including the ones added since this page was written.
Texting and SMS
Texting and SMS guides
How to forward text messages to another number, phone or inbox
Carrier call forwarding does not move text messages — it is a voice feature. To forward texts you either turn on message sync between your own devices, use a third-party auto-forwarding app, ask your carrier whether they offer SMS forwarding, or move the number to a platform where messages arrive in a shared inbox.
How to set up an automatic text reply
iPhone has Driving Focus, which auto-replies only while you are driving, and Focus modes that can reply to chosen contacts. Android varies by manufacturer, with some builds offering scheduled replies. Neither handles business hours properly, which is why a scheduled auto-reply belongs on a business messaging platform.
How to text from a different number than your own
Get a second number and text from it: a business messaging platform, a second line on your existing phone, or a dual-SIM setup. Sending a message that displays somebody else's number is spoofing rather than a feature, and carriers filter it aggressively even where it is not unlawful.
What happens when you text a number that blocked you
The message sends normally and is discarded at the other end. You get no error, no bounce and usually no delivery report either way, which is why nothing on your screen distinguishes being blocked from a phone that is switched off. Delivery receipts are not evidence in either direction.
How to text over wifi when you have no signal
Messages sent through an app — iMessage, WhatsApp, a business texting platform — travel over data, so they work on wifi with no cell signal. Standard SMS between two ordinary handsets needs the carrier network, unless you enable wifi calling on the line, which carries SMS over wifi too.
SMS international format: how to write a number so the text arrives
International standard format is E.164: a plus sign, the country code, then the national number with no spaces, dashes or leading trunk zero. A UK mobile written 07700 900123 becomes +447700900123. That single form works from every country and every platform.
All texting and sms guides
The full section, including the ones added since this page was written.
Frequently asked questions
What is the difference between these guides and the blog?
A guide answers a mechanical question you have right now — which code forwards this line, why the mailbox is silent. A blog post argues something: why connect rate beats dial count, why per-seat pricing costs more than it looks. Guides tell you what to press; posts tell you what to think.
Are the carrier codes on these pages verified?
Yes, and where a carrier is missing it is because we could not verify it. Verizon publishes its star codes openly and that guide cites the page they came from. Guides for carriers whose documentation we cannot check are held back rather than filled in from memory, because a wrong forwarding code wastes an afternoon.
Do these apply outside the United States?
The GSM codes behind forwarding — the ones beginning with a star and a hash — are broadly international, but each carrier decides which it supports and what it charges. Treat the mechanism as portable and the specific code as local.
Why does a phone platform publish guides about carrier features?
Because the honest answer to most of these questions ends in the same place: the carrier feature does one thing, in one direction, with no schedule and no record of what happened. Knowing exactly where that wall is makes it obvious when a business needs routing rather than a star code.
Sources
- Combating Spoofed Robocalls with Caller ID Authentication — Federal Communications CommissionThe STIR/SHAKEN framework, the attestation levels carriers sign calls with, and the mandate requiring providers to authenticate caller ID.
- 47 U.S.C. § 227 — Restrictions on the use of telephone equipment — Cornell Legal Information InstituteThe Telephone Consumer Protection Act itself — the consent requirements, calling-hours limits, and private right of action.
- ITU-T Recommendation E.164 — The international public telecommunication numbering plan — International Telecommunication UnionThe international number format, the 15-digit maximum, and how country codes and national numbers compose.
Every guide here ends the same way
Carrier features move one line to one other line. A business needs rules: hours, overflow, recording, and a record of what happened. That is the product.