A service business sends two fundamentally different kinds of message. "Your technician Mike is on the way, ETA 20 minutes" is one kind. "Spring AC tune-ups are open, book now" is the other. They look similar in a phone's inbox. Under the law and the carriers' rules, they are different things with different requirements, and treating them the same is how businesses get tripped up.
Here is the distinction, why it matters for both email and text, and how to keep the two cleanly separated in your systems.
The two categories
Transactional (or informational) messages exist because of a relationship or transaction the customer already has with you. Appointment confirmations, reminders, on-the-way notices, invoices, receipts, service updates, password resets, and responses to a customer's own inquiry. The customer needs or expects them as part of doing business with you.
Marketing (or commercial) messages promote something. Offers, seasonal promotions, new services, newsletters, referral asks, and any message whose main purpose is to get the customer to buy.
The line is about the primary purpose of the message, not the channel or the tone. A reminder that ends with a coupon is a marketing message wearing a reminder's clothes.
Why it matters for email
Under CAN-SPAM, a commercial email must identify itself as an ad if the recipient has not consented, must include a physical mailing address, and must carry a working opt-out that is honored promptly. Transactional emails are exempt from most of those requirements, as long as the transactional content is primarily what the email is for.
Google's and Yahoo's bulk sender requirements, in force since 2024, add practical rules for anyone sending marketing volume: authenticated sending (SPF, DKIM, DMARC), one-click unsubscribe, and a spam complaint rate kept low. Transactional email is judged separately by the mailbox providers, which is one reason to send it from a different stream or domain. When your promotional list triggers complaints, you do not want your invoices landing in spam too. The deliverability side of this is its own topic.
Why it matters for SMS
This is where the difference has teeth. Under the TCPA and its FCC rules, informational texts to a mobile number generally need the customer's prior express consent, which providing a phone number in the course of a transaction can establish. Marketing texts need prior express written consent: a clear, affirmative agreement to receive marketing messages, with the required disclosures, that you can produce on demand.
A customer who gave you their number to book a service has consented to the appointment reminder. They have not necessarily consented to "20% off duct cleaning this month." Sending the second to a list collected for the first is the most common TCPA exposure we see in the trades, and the basics of SMS compliance come down to keeping those two consents separate.
Carriers enforce their own layer through the 10DLC registration system. Your registered campaign describes the message types you send, and messages outside that description get filtered. A campaign registered as transactional that starts sending promotions is a filtering problem waiting to happen.
Keeping them separate in practice
Two consent fields in the CRM. One for transactional contact (which most customers grant simply by booking), one for marketing, with the date, the source, and the exact language they agreed to. Every marketing send checks the second field, never the first.
Two message streams. Transactional messages go from a dedicated sending setup, whether that is a separate email sending domain or a separately registered SMS campaign. Marketing goes from another. A complaint spike on one does not take down the other.
Content discipline. Reminders remind. Confirmations confirm. Do not tuck an offer into the bottom of an on-the-way text. If you want to promote the maintenance plan, send a marketing message to people who have consented to marketing.
Opt-out on everything. Transactional texts are not strictly required to carry opt-out language in every case, but including "Reply STOP to opt out" costs nothing, satisfies carriers, and removes an argument. Honor STOP immediately across both streams.
A written policy. One page that defines the two categories, lists which messages fall in each, and states the consent required for each. When someone new starts writing messages, hand them the page.
The gray areas
"Your annual tune-up is due." Informational if it is a reminder about a service plan the customer holds. Marketing if it is a pitch to someone who does not.
Review requests. Generally treated as related to the transaction and sent after it, but the FTC's rules on how you ask apply regardless, and the safest practice is to send them under the same consent you would use for marketing.
"Thanks for your business, here is what to check next week." A post-job helpful message with no offer is on the informational side. Add a coupon and it moves.
When in doubt, treat the message as marketing and send it only to the marketing-consented list. The cost of over-caution is a slightly smaller audience. The cost of the other error is a demand letter with a per-message figure attached.
The consent fields and the two sending streams are set up as part of every managed CRM build-out, and the SMS consent page on this site is an example of the disclosure language a marketing opt-in needs.
Frequently asked questions
Can I collect both consents in the same form?
Yes, as separate, unchecked boxes with their own disclosure language. A pre-checked box or a single combined checkbox does not establish marketing consent.
What if the customer texts me first?
You can reply about the thing they texted about. That does not grant marketing consent.
Do I need separate phone numbers for each stream?
Not always, but separately registered campaigns are the cleaner setup, and some platforms require it. Your SMS provider can advise on the current registration rules.
Does this apply to a one-person business?
Yes. The rules attach to the message, not the size of the sender.