Setup guide
How to forward your HVAC calls
to an answering service
Call forwarding sends your business calls to another number. For answering-service cover, forward all calls at night, or set conditional forwarding so calls go through when you're busy or don't answer. The codes differ by carrier and phone system. This guide lists the codes carriers publish and how to test the setup.
Last updated October 31, 2026
The steps
- 1Find out what phone line you have: a mobile plan, a traditional landline, or a cloud or VoIP phone system.
- 2Choose when calls should forward: all calls, only when you're busy or don't answer, or only after hours.
- 3Get your forwarding number. VoiceBridg gives you the number to forward to when you start.
- 4Set up forwarding with your carrier's code or your phone system's settings. The table below lists published codes.
- 5Test it from another phone, including the busy and no-answer cases.
- 6Write down how to turn forwarding off. You keep your number and can switch it off whenever you like.
Codes by carrier
These are the codes each carrier publishes. Options depend on your plan and line type, so confirm with your carrier before relying on them.
| Line type | Forward all calls | When busy or no answer | Turn off |
|---|---|---|---|
| Verizon wireless | Dial *72, then the 10-digit number | Dial *71, then the 10-digit number. Calls forward after 3 to 6 rings instead of going to voicemail. | See Verizon's turn-off page for your line |
| AT&T Phone for Business (traditional line) | Dial *72, the number, then # | Busy: *90, the number, then #. No answer: *92, the number, then #. | *73# for all calls, *91# for busy, *93# for no answer |
| T-Mobile | See T-Mobile's short codes page | No reply: **61*1, the number, then #. Busy: **67*1, the number, then #. Unreachable: **62*1, the number, then #. | ##61#, ##67# or ##62#, or ##004# to reset all three |
| Cloud or VoIP business phone systems | Set "Always" in the admin or user portal | Set "When busy" and "When no answer", and choose how many rings come first | Switch the setting off in the same portal |
Things that go wrong
- Forwarding only works to a number your carrier allows. Verizon says international forwarding isn't available.
- Verizon says star codes may not work outside its wireless coverage area.
- If a code doesn't work, contact your carrier's customer service to turn forwarding on or off, as Verizon advises.
- An extra key press while entering the number can stop it being recognised. Enter the digits slowly and listen for the confirmation.
Test before you rely on it
- Call your business number from a different phone and check it reaches the answering service.
- Let your own phone ring unanswered, and then busy it, and check conditional forwarding works in both cases.
- Check that you can switch forwarding off, and that your own number still works.
Sources
- Verizon: Turn Call Forwarding On from Device · Checked October 31, 2026.
- AT&T: Manage Call Forwarding, AT&T Phone for Business · The page says last updated December 7, 2022. Confirm for your line.
- T-Mobile: Self-service and short codes · Codes as listed by T-Mobile, checked October 31, 2026. Confirm with T-Mobile before use.
Written by the VoiceBridg team.
FAQ
Common questions
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Do I keep my business phone number?
Yes. Forwarding only sends calls to another number. Your number stays yours, and you can turn forwarding off whenever you like.
Should I forward all calls or only some?
Many HVAC companies forward all calls at night and on weekends, and use busy and no-answer forwarding in the day. Pick the pattern that matches when you miss calls.
Which code should I use for my carrier?
Use the table in this guide as a starting point, then confirm with your carrier. Codes and options depend on your plan and line type.
How do I check forwarding is working?
Call your business number from another phone and check the call reaches the answering service. Test the busy and no-answer cases as well.