How to divert only the calls you miss - without losing them to voicemail

Two codes, dialled from your business handset. ##002# clears every divert already on the line, voicemail's own included. Then **004*<the number that should catch them># hands over the calls you don't answer, are already on, or miss with no signal. Your phone still rings first. You still take what you can.

That second code is a conditional divert: call forwarding that fires only when the call would otherwise go unanswered. Dialled on its own it can lose to a divert already on the line, which is why the clearing code goes first.

Which divert code does what?

Four conditions, four codes, plus two that act on several at once. The digits come from 3GPP TS 22.030, the man-machine interface spec GSM handsets are built to, which is why Vodafone UK's divert page and Odido's voicemail page both start their no-answer code with **61*.

When the call arrives	Register the divert	Cancel it	Ask what's set
Always, before your phone rings	**21*<number>#	##21#	*#21#
You didn't answer in time	**61*<number>#	##61#	*#61#
You're already on a call	**67*<number>#	##67#	*#67#
Phone off, or no signal	**62*<number>#	##62#	*#62#
All three conditional rows above, at once	**004*<number>#	##004#	*#004#
Every divert on the line	-	##002#	-

The prefixes carry the meaning. ** registers a rule, ## erases one, *# interrogates. Dial, press call, and wait for the network to accept or reject the request.

Treat **21* with respect. It is unconditional: the network forwards every call, whatever state your phone is in. Useful when you want the front door answered for you, wrong if you still want first refusal on the job.

Why does voicemail still get there first?

Because voicemail is a divert too, already sitting in the slots you are trying to use. A moderator on KPN's own community puts it plainly: voicemail works through divert rules in the network, which send the call on when you don't answer, are busy or have your phone off.

You can see the machinery in your network's own instructions. Odido tells you to change the ring time by dialling **61*+31624<your ten digits>*11*<seconds># - that is the no-answer divert, pointed at a voicemail number that happens to be yours. Vodafone UK offers 1211 to put you back on "the standard voicemail service if you're busy, unreachable or don't answer in 15 seconds". Three conditions. The same three.

So a divert does not sit alongside voicemail. Each code takes over its own condition and leaves the others where they were, and that is exactly where it goes wrong:

• You replaced one rule and left two. Dial **61* on its own and a call that finds your line busy still lands on the beep. **004* covers all three in one dial.
• An old unconditional divert is beating you. If **21* is still active from some job two winters ago, the network turns down a new busy or no-answer divert, and every call follows the old one. ##002# erases it along with everything else, which is why it goes first.
• Voicemail goes down with everything else. ##002# is not selective, so it takes the voicemail rules too. If you are handing the calls to a fallback, that is the point. If it isn't, each network in the table below publishes a way back - 1750 on O2, 12331 on KPN and on Vodafone NL, VM ON texted to 150 on EE, 1211 on Vodafone UK, Mijn Odido on Odido.

How long should the phone ring before it diverts?

Between 5 and 30 seconds, in steps of five, and you pick the number yourself when you register the rule. The spec calls it the No Reply Condition Timer and stops at thirty, so a divert code cannot ask for longer.

The timer goes on the end of the code:

**61*<number>*11*20#

20 is the seconds, and 11 is the basic service group for telephony, so the rule covers voice calls and leaves your texts alone. Vodafone UK writes it with *10* instead - that is the same field, set to all teleservices rather than voice only. Both are legal values from the spec's own service list, so use whichever your network prints.

Set it to 20. Fifteen is Vodafone's default in both countries, and I think it is too short to get out from under a sink and decide whether to take the call. Thirty seconds of ringing, to someone standing in a wet kitchen, feels like being ignored.

What does your own network do by default?

Each cell is what the network's own help page says, and each row describes the voicemail rule your own divert replaces.

Network	Rings before voicemail	Timer adjustable?	Switch voicemail off
EE (UK)	not stated	not stated	text VM OFF to 150
O2 (UK)	not stated	not stated	dial 1760, back on with 1750
Vodafone (UK)	15 seconds	yes, in the code	dial 1210, back on with 1211
KPN (NL)	20 seconds	no - "helaas kan je dit niet zelf instellen"	call 12339, back on with 12331, or text UIT to 1233
Odido (NL)	20 seconds	yes: 5, 10, 15, 20, 25 or 30	in Mijn Odido
Vodafone (NL)	15 seconds	yes, 5 to 30 seconds	call 12330, back on with 12331

Three (UK) is the gap in that table. Its old voicemail help page no longer loads, and the ring-time answers a search turns up sit on its community forum, so budget a call to Three's support rather than an evening of dialling codes at it: 337 from a Three Business phone, or 333 on a personal plan.

KPN is the one to watch. Its page puts the ring time at twenty seconds and says you cannot change it yourself. In the spec the timer belongs to the rule you register, and a value you register replaces the provider's default. KPN's page does not say whether it honours one set in your own **61* code, so set it, then ask the network with *#61#.

Should you divert everything instead?

Depends on whether you want to be interrupted. The two modes are genuinely different businesses, not settings.

	Divert everything (**21*)	Divert only what you miss (**004*)
Does your phone ring?	No	Yes, first
The caller reaches	Whatever you diverted to	You, or the fallback if you can't get to it
Good when	You want the phone to stop owning your day	You want to answer what you can and keep the rest
The risk	You never speak to a customer first	Nothing catches the call unless the fallback is real

That last row is the whole point. A conditional divert is plumbing: it moves the call somewhere. Whether that somewhere books the job is a separate question, and voicemail has already answered it - fewer than 3% of callers pushed to voicemail leave a message, on Invoca's platform data, published in May 2024. Point your new divert at the same voicemail box and you have built a longer corridor to the same empty room.

Diverting the call is the easy half. The half that pays is what picks up at the other end.

What the calls are worth is measurable. ServiceTitan's data from more than 3,000 trade businesses on its software put plumbing's call booking rate at 43% in June 2022, the highest of the trades it reported that month. That is June 2022 data from businesses in the United States and Canada, so treat it as a yardstick: at that rate, roughly two in five calls became a job. It's worth counting your own missed calls before you decide how much that fallback is allowed to cost.

What if your business line is a landline or VoIP?

Then you need a different set: the codes above are the mobile (GSM) ones. KPN's fixed line takes its own, with a single star - *21* forwards everything, *61* forwards after five rings, *67* forwards while you are on a call, and #21#, #61# and #67# switch them off again. For a VoIP number or a hosted phone system, look in the provider's control panel or app.

Two things travel across: the destination number, and the choice between forwarding everything and forwarding only what you miss. Set both to match, and test it the same way.

How do you know it worked?

Interrogate the line, then ring it. *#61# asks the network, which answers from its own records with the number your no-answer rule forwards to and the seconds it waits first.

Then make a real call from a phone that is not your business line. Let it ring out without touching it. Whatever you diverted to should pick up once your handset stops ringing. If it doesn't, interrogate *#21# before you re-dial anything: an unconditional divert left over from an earlier setup takes every call, and your no-answer rule never gets a say.

Do it again after any change of SIM or contract. A divert that has quietly stopped firing looks exactly like a quiet day.

Where the call should land

A divert needs a destination that can do something. A mate's phone can't see your diary, and a voicemail box gets under 3% of callers to speak. SwiftGuard's AI receptionist picks up within two rings and takes down the caller's details and the problem. Once your Google Calendar is connected, it books the job into it while the caller is still on the line.

SwiftGuard's setup screen prints both codes, with your SwiftGuard number already in the second once one has been assigned to you, so there is nothing to type by hand: the forwarding walkthrough has the whole sequence, including which mode to save before you dial. That screen is built for Dutch lines; SwiftGuard does not set up forwarding for UK numbers. On a UK mobile the standard codes above still apply (Vodafone UK prints the same ones), and voicemail is still the thing to get out of the way first.