If you run an HVAC shop or any home service business, you've probably been pitched on SMS as the next big lead-gen channel. The reality is messier. Cold texting strangers will burn your sender reputation, invite TCPA complaints, and convert worse than a cold call. But SMS to your existing customer base? That's one of the highest-ROI channels you'll find.
Here's how to think about it, and how to set it up without lawyering yourself into a corner.
Why cold SMS is a dead end for HVAC
Cold texting used to work because carriers didn't filter much and consumers were curious. Both of those things have changed.
Carriers now require every business-to-consumer SMS sender to register their brand and campaigns through 10DLC (the A2P framework for 10-digit long codes). Unregistered traffic gets throttled or blocked outright. Even when you do get registered, sending to numbers that didn't opt in produces high STOP rates and spam reports, which carriers use to dial down your throughput or shut you off. We covered the broader mechanics in our business SMS guide if you want the full background.
The TCPA layer makes it worse. Texting consumers without prior express written consent exposes you to statutory damages of $500–$1,500 per message. A single plaintiff's attorney with a 5,000-message list is looking at a settlement worth real money. "But I bought the list from a lead vendor" is not a defense.
And practically: most people treat unknown-number texts the same way they treat unknown-number calls. They ignore them or block them. Response rates on cold HVAC texts are bad enough that even if compliance weren't an issue, the unit economics wouldn't pencil out.
Where SMS actually prints money for home services
The channel works when there's an existing relationship. You installed their system. You did their spring tune-up. They called for a quote last fall and didn't book. These people already know your brand and have a reason to want to hear from you.
The highest-ROI use cases:
- Seasonal tune-up reminders. Text your maintenance list in early spring (AC) and early fall (heat) with a booking link. Conversion on a warm reminder beats any cold channel.
- Service plan renewals. A two-message sequence 30 and 7 days before expiration recovers a meaningful percentage of lapsed plans.
- Post-service follow-up and review requests. Same-day text with a one-tap Google review link. This is where most shops leave money on the table.
- Appointment confirmations and ETA updates. Reduces no-shows and the "where's my tech?" calls that clog your dispatch line.
- Quote follow-ups. If you sent a proposal and didn't hear back, a short text 3 and 10 days later closes deals that email won't. The same logic applies to inbound calls you couldn't pick up — our missed-call auto-text playbook breaks down the mechanics.
- Emergency capacity offers. Heat wave hits, you have a same-day cancellation, text it to your local maintenance list.
Notice what's not on that list: blasting promotional offers to purchased lead lists.
Getting through 10DLC registration
If you're going to send any business SMS in the US, you need 10DLC registration. There's no path around it. Here's what you actually need:
- Brand registration. Your legal business name, EIN, address, and website. The EIN has to match your registered business; vetting fails when these don't line up.
- Campaign registration. A description of what you'll text and to whom. For HVAC, you'll typically register a "Mixed" or "Customer Care" use case covering appointment reminders, service updates, and account notifications. If you also want to send promotional offers, register a separate Marketing campaign.
- Sample messages. Carriers want to see the actual templates you'll send, including the opt-out language.
- Opt-in description and proof. You have to describe exactly how customers consent — checkbox on your booking form, verbal opt-in during service call logged in your CRM, etc. Keep records.
Approval usually takes a few business days. Rejections almost always come down to vague campaign descriptions or missing opt-in details — we walked through the most common rejection causes in what carriers actually require. Be specific.
What your messages must include
Every campaign needs:
- Identification of your business in the first message
- Clear opt-out instructions ("Reply STOP to unsubscribe")
- Help instructions ("Reply HELP for info")
- Message frequency disclosure on the opt-in surface
- Standard "Msg & data rates may apply" language at opt-in
A compliant first message looks like:
Acme HVAC: Hi Jane, this is a reminder your AC tune-up is
scheduled for Tue 4/15, 9-11am. Reply C to confirm,
R to reschedule. Reply STOP to opt out, HELP for help.
Building an opt-in flow that holds up
The TCPA standard for marketing messages is prior express written consent. That's a higher bar than "they gave us their number." Operationally:
- Booking forms: Add an unchecked checkbox with explicit language: "I agree to receive appointment reminders and service offers from Acme HVAC by text. Message frequency varies. Msg & data rates may apply. Reply STOP to opt out. Consent is not a condition of purchase." Store the timestamp, IP, and form version.
- In-person and phone intake: Train techs and CSRs to ask explicitly: "Can we send you appointment reminders and seasonal offers by text?" Log the answer in your CRM with a date.
- Existing customers without explicit consent: Service-related transactional messages (today's appointment, ETA, invoice) generally fall under an established business relationship for informational use, but marketing messages do not. When in doubt, run a re-permission campaign by email first.
- Honor STOP immediately and forever. Suppress that number across every campaign. Carriers and plaintiffs both watch this.
Keep an audit trail. If a complaint lands, you want to pull up the exact form, timestamp, and consent language in under a minute.
A 90-day rollout that actually works
Don't try to launch everything at once. A workable sequence:
Days 1–14: Register your brand and one campaign (Customer Care, covering reminders and confirmations). Add the opt-in checkbox to your booking form and tune-up scheduling pages. Train CSRs on the verbal opt-in script.
Days 15–45: Turn on appointment confirmations and ETA texts only. These are transactional, low-risk, and immediately reduce no-shows. You'll start building a clean opted-in list.
Days 46–75: Layer in post-service review requests and quote follow-ups. Track reply rates and STOP rates. If STOPs are above 2–3% on any message type, rewrite it.
Days 76–90: Register a Marketing campaign if you want to run seasonal tune-up promos. Send your first seasonal blast only to customers who opted in to marketing specifically.
What to do next
If you take one thing from this: stop thinking of SMS as a cold acquisition channel for HVAC. It isn't, and the people selling it to you as one are setting you up to get throttled or sued. Use Google Ads, Local Services Ads, and Facebook for acquisition. Use SMS to wring more revenue out of the customers you've already won — tune-up reminders, review requests, quote follow-ups, plan renewals.
The operational lift is real: 10DLC registration, an audited opt-in flow, suppression lists, and message templates that actually comply. If you'd rather not stitch all that together yourself, our Phone System and SMS plans handle the carrier paperwork and tracking out of the box.
Start with confirmations and reminders. Get those clean. Everything else builds on that base.