Can you text your clients? How to ask for SMS consent

The short version

Yes, when you have the permission required for the message and the way you send it. Having a client's number or a booked appointment does not settle that question. For appointment texts through a business platform, use a documented written or electronic opt-in. Keep promotions separate and get a separate written opt-in before sending them. When a client asks you to stop, act promptly.

This guide covers US businesses as of October 6, 2026. It is general information, not legal advice. Requirements depend on the message, sending technology, recipient's location, and provider terms. Example wording and Desk's consent settings do not establish legal compliance. Have qualified counsel review your consent process before launching or changing a messaging program, especially promotions.

Separate appointment messages from promotions

The distinction matters because clients may want a reminder without signing up for offers. CTIA's industry guidance separates conversational, informational, and promotional messages. The table below gives a practical approach; it is not a complete statement of the law.

A reminder with a coupon or an invitation to buy more can become a promotional message. Keep appointment texts to the visit: who, when, where, and how to change it. A deposit or payment link should relate to a transaction the client requested or agreed to.

Ask while the client books

Offer an optional checkbox the client selects themselves. Leave it unchecked, and let them request an appointment without agreeing to SMS. Explain:

• the business sending the texts, and any platform sending on its behalf;
• the types of messages the client is agreeing to receive;
• the expected frequency or a truthful explanation that it varies;
• that message and data rates may apply;
• how to stop messages and get help;
• that consent is not required to book or buy.

These points combine provider requirements and industry guidance. They do not replace any additional disclosures or signature requirements that apply to your program.

For example, an appointment-only opt-in could start with: "I agree to receive appointment reminders and updates from [Business] through [Platform]. Frequency varies with my appointments. Message and data rates may apply. Reply STOP to cancel or HELP for help. I can book without agreeing to SMS."

Adapt the example to the messages you actually send, your provider's terms, and your working STOP and HELP process. Link to the relevant terms and privacy policy. This is a service-message example, not a marketing consent form.

Do not assume an oral yes is enough for your platform. Twilio's Messaging Policy, updated April 13, 2026, includes a specific rule for software services used by business customers. Those services must require their customers to obtain prior express written consent from downstream recipients. That requirement is separate from Twilio's general guidance for informational messages.

If you ask at a visit, give the client a way to provide the required written or electronic opt-in. Keep the phone number, business name, consent wording shown, date, and method. Retain the proof according to your legal and provider requirements. A staff member turning on a consent setting is not, by itself, proof that the client agreed.

Check clients you already have

A saved phone number, a past purchase, or a move to a different app does not by itself prove permission for your current SMS program. Check the original sender, message purposes, consent record, and any opt-out. A change of app does not necessarily cancel valid permission, but you need to establish that it covers the new setup.

If you cannot establish that permission, collect a fresh opt-in through your booking page or a written form. Share the booking link in person, through an email the client is permitted to receive, or on your public social page. Do not start an SMS conversation just to ask for permission when you have no basis to send that text.

In Desk's web import flow, clients imported from Square, Vagaro, and DIKIDI files start with the SMS consent setting off. Booksy files can carry a communication-agreement field that Desk imports. An imported flag still needs review: check what the client agreed to and whether it covers your business, purposes, and provider requirements.

Keep a separate record of requests to stop. Re-importing contacts or adding a client again should not erase that record or become permission to resume texts.

When a client asks you to stop

Make it easy to stop messages. As an operating practice, handle clear requests by text, email, or in person promptly. Recognize STOP and the other standard keywords: QUIT, END, REVOKE, OPT OUT, CANCEL, and UNSUBSCRIBE.

1. Pause further texts covered by the request and record the number, date, and request. If the scope is unclear, pause sending while you resolve it.
2. Use your provider's opt-out process and update the client's consent setting. If they ask outside SMS, record and process that request too.
3. If your provider sends an unsubscribe confirmation, do not add another manually. Any confirmation should contain no promotion. Check the rules for its timing and content.
4. Keep the opt-out record when you change apps or import contacts. Resume only after you have established a valid basis to do so.

Provider policies can require an immediate stop, so do not treat a legal processing deadline as permission to keep sending. For example, Twilio allows one final opt-out confirmation. It prohibits further messages unless the recipient chooses to receive them again and provides new express written consent.

In Desk's web dashboard, the client's profile has an SMS consent checkbox. Turn it off when the client withdraws permission. If you are unsure which messages a provider's automatic block covers, check with support before relying on it.

Check the law and the provider's terms separately

Federal TCPA consent rules depend in part on the sending technology. A scheduled message is not automatically an "autodialer" message under federal law. Marketing texts can also be subject to Do Not Call rules and state laws even when sent manually. An existing business relationship is not a blanket texting exception and does not override a request to stop.

CTIA publishes voluntary industry guidance. Providers and carriers set their own messaging conditions. Their requirements can be stricter than the consent needed under a particular law. A2P 10DLC registration is a carrier process for business messaging through US local numbers; registration does not determine whether each message complies with the law.

Check the rules that apply where your recipients are located, including any limits on sending hours. Daytime sending is sensible, but there is no single time window that settles every state's requirements.

What to check in Desk before you send

Desk's online booking form has an optional, unchecked SMS consent box. Its wording describes service messages from the business through Desk, including confirmations, reminders, booking updates, and payment-related notices. The form also links to terms and privacy information and explains that consent is not required to request an appointment.

Business owners can record consent in a client's profile. Before enabling that setting, obtain and retain the permission required for the messages and provider. The setting does not validate the consent record or cover promotional texts.

Before your first platform message, check a consent record against the wording the client saw. Confirm that the number, business, and message purposes match. Check your opt-out records and confirm how requests to stop will be processed.

Desk offers a Free plan for managing appointments and client records. SMS credits and payment processing are charged separately. You can also try the booking demo.

Sources

Sources reviewed October 6, 2026. This guide does not cover every state law or provider contract.

• 47 CFR 64.1200, eCFR: federal consent, Do Not Call, and revocation rules.
• Twilio Messaging Policy, updated April 13, 2026: consent, software-service customers, proof, and opt-outs.
• CTIA Messaging Principles and Best Practices, May 2023: voluntary industry guidance on message purposes and consent.
• Facebook, Inc. v. Duguid, April 1, 2021: the federal definition of an autodialer.
• Twilio's A2P 10DLC guide: carrier registration and the distinction between platform and person-to-person traffic.