Short, written, once, with a date and an instruction. That is the whole recipe.

The message needs to do four things and nothing else: give the new number, say when it takes over, tell them to save it, and say what happens to the old one. Anything else you add — the reason, the apology, the reassurance — gets skimmed past, and the number gets skimmed with it.

Here is the shape:

My practice number is changing. From {{date}}, please use {{new number}} for calls and texts. Could you save it in your phone now and delete the old one? The old number will still reach me until {{date}}, after that it won't.

That is it. No explanation of why, unless the why is clinically relevant. No "sorry for the inconvenience". Practitioners who have moved a whole client base describe the reaction as almost entirely non-existent — people update a contact and carry on. The anxiety about this conversation is disproportionate to the conversation.

The one addition worth making: if the new line behaves differently from the old one — different hours, a greeting instead of you, a reply window — say so in the same message. It is a better message anyway, and it means the boundary arrives as a choice rather than as a side effect of the switch.

When should I send it?

After the new line is fully working and before you update anything public.

Test the new number first — call it, text it, leave a voicemail, check the greeting is the one you want. A client should never be the first person to discover a problem with it.

Then send the message, then update your website, signature, listing and forms. In that order, so that nobody encounters the new number in the wild before they have heard it from you.

Should I text it or email it?

Both, if you can. They do different jobs.

A text from the new number is the useful one. It puts the number in their phone in the place they actually look, and gives them something to reply to. A number inside an email has to be retyped.

Email is the durable one. It survives, it can be searched, and it reaches the clients you do not have text consent for.

If you only do one, do the text — but only where you have consent to text that person, and only within whatever your consent covers. Consent here attaches to the channel, not to the message: Ontario's psychotherapy College expects registrants to "outline appropriate uses of technologies with clients (e.g., emailing or texting only for booking appointments, secure online platforms for the provision of therapy)" (CRPO, Standard 3.4 commentary).

So the question is not whether a change-of-number notice needs a consent of its own. It is whether texting this person is inside what you already agreed. If your form says texts are for scheduling, a message about the number they schedule on sits comfortably in that. If you have no text consent from someone, email them instead.

The federal anti-spam rules are a different question and a narrower one — they reach messages that are "commercial in nature" (CRTC), which is not the same category as telling your own client how to reach you.

How many times should I say it?

Twice, plus a passive net.

Once when you announce it. Once as a short reminder near the date the old number stops working. That is enough — a third message starts to read as anxious, and this audience notices tone.

The passive net is the greeting on the old number, stating the new one slowly and twice. That catches everyone the two messages missed, which is a real group: the clients who contact you least often are the ones least likely to have read either message, and they are also the ones whose eventual call matters most.

Who else needs telling?

Clients are the easy part. The long tail is everyone else with your number written down.

• Referral sources — family doctors' offices, other therapists, an EAP, a school

• Anyone you are in ongoing correspondence with about a shared client

• Your directory listing, and any second one you forgot about

• Your accountant, your insurer, your professional liability provider

• Your own emergency-contact arrangements, if a colleague covers for you

A doctor's office with your old number on a sticky note will use it for years after every client has moved over. Those are worth a specific, separate email rather than being folded into a general announcement.

What about people who are not clients yet?

The people you have not met are the ones you cannot message, and they are the reason the public surfaces matter more than the announcement does.

Someone who found your listing last month and is working up to calling has your old number saved in a note on their phone. You will never know about them. The only thing that catches them is the old line still answering with the new number, for longer than you think you need it.

What not to do

Don't announce it verbally at the end of a session and leave it there. It will not survive the week.

Don't announce it before the port or the setup is confirmed. If the date slips, you have to send a correction, and corrections are what actually confuse people.

Don't cut the old line the day after the message. The whole point of the message is to buy an overlap; ending the overlap immediately wastes it.

Don't keep giving out the old number. The most common failure after a switch is not clients ignoring the new number — it is the practitioner still handing out the old one from habit, on a form or a signature nobody updated.

The short version

One short written message with the number, the date, and a direct ask to save the contact. Text it from the new line where you can, email it where you can't, remind once near the cutover, and leave the old number speaking the new one for a good while afterwards. Then go tell the doctors' offices.

About Rivet

Rivet is a Canadian practice line built for therapists — a separate number for calls, texts and voicemail, with video sessions and clinical tools in the same place. Your data stays in Canada, and transcription runs on Rivet's own hardware rather than a third-party AI service.

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