Who this is for
You've signed up and you want calls to actually reach Scarlett. This guide sets the divert on your phone network so calls forward to your Scarlett line, and shows you the exact code to dial for your carrier.
Time: about 5 minutes. You'll need: to be the account owner, and the phone that receives your business number to hand.
You set the divert on your own phone or with your phone provider — not in the Scarlett app. Nothing in the app can turn it on for you. The app gives you the number and the code; you dial it.
Before you start
- Sign up and start your free trial — you need an account, and your business number saved on it.
Why this matters: your customers keep dialling the number they already know. The divert is your network quietly passing those calls to Scarlett's line, so she can pick up when you don't. You keep your number; nothing is transferred away from you.
Steps
1. Find your Scarlett line
Sign in, open Settings, then the Scarlett number tab. Your Scarlett line is the large number at the top of the page — this is where your calls forward to.
You should see: the number under the label The Scarlett line, with the line "Forward calls from [your business number]" beneath it. If that instead warns that no business number is saved, add it first — Scarlett matches incoming calls against it to know they're yours.
2. Choose when calls should divert
Pick a Divert mode. There are three, and most traders start on Always.
| Mode | Diverts when | Best for |
|---|---|---|
| Always | Every call, immediately | Scarlett is your receptionist |
| When busy | You're already on a call | You answer when you can |
| When unanswered | You don't pick up in ~20 seconds | Answer first, Scarlett catches the rest |
You should see: the mode you tapped turn coral, and the badge beside Divert mode update to match. The setting saves as you tap — there's no separate save.
3. Dial the divert code for your network
Under How to divert on your network, choose your network. The page shows the
exact numbered steps for it — on most UK mobile networks that's: open the Phone
app, dial **21* followed by your Scarlett line then #, and tap call. Do
this on the phone that receives your business number.
You should see: your network confirm the divert is on — on most mobiles a
"Service was activated" message. To turn diverting off again later, dial
##21#.
Supported networks: EE, O2, Vodafone, Three, Sky Mobile, plus
BT and Virgin Media landlines (landlines use *21*…# and cancel with
#21#). For anything else, choose Another network for the generic code.
Most traders do this standing on a job, on the mobile itself. The Scarlett number page works the same on your phone — the Scarlett line and the divert modes are right at the top.
4. Prove it worked with a test
Press Test divert on the same page. It rings your business number from the Scarlett line: if the divert is live, the call loops straight back to Scarlett and never reaches your handset. That single test proves the whole path.
Read the result, then follow Test your divert and read the result for what each outcome means.
Verify it worked
You're done when Settings → Scarlett number shows your divert as Divert working after a test. Until it does, assume it isn't on — the divert lives on your carrier's network, so the app cannot see it without a test. A quick real-world check: ring your business number from a different phone and let it divert; Scarlett should answer.
Troubleshooting
The Test divert button is greyed out. You haven't saved a business number yet. Add it in the Your business number field on the same page — that's the line Scarlett rings to run the test.
Your phone rang instead of Scarlett. The divert isn't active. Re-dial the code for your network and check you copied the Scarlett line exactly. If you set the mode to When busy or When unanswered, that's expected — the test only proves an always-on divert.
The test says your calls arrive "anonymously" / your number is stripped. Your divert works, but your network doesn't pass through which number the call was for, so Scarlett can't tell your calls apart from anyone else's. The fix is your own dedicated Scarlett line — see Get your own Scarlett line.
It worked, then stopped after I changed SIM, handset or network. Diverts don't survive a network change. Re-dial the code to set it again.
"That doesn't look like a UK phone number."
The business number wasn't recognised. Enter it as 07… for a mobile or 020…
for a landline — Scarlett only accepts UK numbers.
What's next
- Test your divert and read the result — interpret every test outcome.
- What Scarlett says and does on a call — the greeting, the recording notice, and what she'll never do.
- Scarlett isn't answering — if calls still aren't reaching her.