A service business loses £100 per no-show. Multiply that by even two cancellations per week, and you're handing away £10,000 annually to customers who simply forget. SMS reminders cut that bleed. But the real story isn't binary: SMS alone stops 40% of no-shows. Deposits stop another 30%. And when you layer both—SMS + a non-refundable deposit—you're approaching zero-show territory. The problem: most booking platforms don't offer native SMS at all. Calendly sends email only. Acuity and Orin both offer SMS natively, which matters because every tool swap costs time and creates failure points. Here's what the data actually shows, and what's worth the money. The 40% myth: SMS timing beats frequency Not all SMS reminders are equal. The data is clear: two reminders at precise moments beat daily nagging. 24-hour reminder: Converts 15–20% of would-be no-shows. Gives customers time to reschedule without friction. 2-hour reminder: Converts another 20–25%. At this point, the appointment feels real and imminent. The ask to confirm or cancel is harder to ignore. Multiple daily reminders: No gain. Just churn and unsubscribes. The 40% figure (often cited by Acuity and Calendly in their own research) reflects the combined effect of both reminders hitting the right moments. A single 24-hour SMS alone cuts no-shows by about 15–20%. The 2-hour nudge does the real work. Cost per reminder: £0.01–£0.05 depending on your SMS provider. If you send two per appointment, that's £0.02–£0.10 per booking. At 100 bookings per month, you're spending £2–£10 on SMS to save £2,000–£3,000 in no-show losses. The math is obvious. Email reminders: cheaper, slower, easier to ignore Email is free (or bundled into your booking platform). It's also nearly useless for preventing no-shows. Email reminder conversion rates hover at 5–10%. Why? Because email lives in noise. It arrives with 50 others. The notification doesn't trigger urgency the way SMS does. By the time a customer opens their email and processes the reminder, the appointment is hours away—too late to reschedule easily. Email works for confirmations and follow-ups, not reminders. If you're using email alone to remind customers of appointments, you're saving money and losing bookings in equal measure. The trade: Email is free; SMS is 2–5% of your booking revenue. But SMS stops 4–5x more no-shows. Deposits and non-refundables: the 30% game-changer A £20 non-refundable deposit (or 50% of the service fee) changes behavior fundamentally. No-show rates drop another 30% beyond what SMS alone achieves. Why? Psychology. Money paid is different from money owed. A customer with £20 at stake will call to reschedule rather than vanish. The deposit doesn't have to be large—it just has to exist. The cost to you: processing. Most booking platforms with native SMS also handle deposits natively (Acuity, Orin). If you're using Calendly or another email-only platform, adding deposit collection means integrating Stripe or PayPal separately. That's friction—both technical and customer-facing. Customers see a second payment page, which kills 3–8% of initial bookings. Deposit logistics: Non-refundable: Simplest. Clearest behavior change. Slight ill-will if customer needs to reschedule (but they will, instead of ghosting). Refundable (24-hour notice): Keeps goodwill. Still prevents no-shows because most customers won't bother trying to get the refund. Slightly higher admin for you. Credit-toward-service: Best for retention. Customer can reschedule at no cost, but the money doesn't leave your account. Requires a booking platform smart enough to track credit balances. At 100 bookings per month with a £20 deposit, you're holding £2,000 in customer deposits. That's working capital you didn't have before. And it almost never comes back as a refund request—most customers reschedule. Which platforms actually offer native SMS and deposits? This matters because native beats bolted-on. Calendly: Email reminders only. No SMS. No deposit collection without integrations. If you want SMS reminders, you'll layer Twilio or another SMS service, which means manual setup and a separate bill. Cost: £0 (Calendly) + £50–200/month (SMS service) = expensive for what you get. Acuity: Native SMS reminders at 24 and 2 hours. Native deposit collection (non-refundable or refundable). Integrates with Stripe. Solid UX, but priced at $16–$199/month depending on feature tier. SMS reminders are included; deposits require the higher tier. Orin: Native SMS and WhatsApp reminders. Native deposit collection with full credit tracking. Invoicing and deposits live in the same system, so refunds and rescheduling are actually traceable. Deposits flow straight to your invoice. No separate integrations needed. Pricing includes SMS—you pay per message (£0.01–£0.05), not per feature. Square Appointments: SMS reminders (via Twilio integration). Deposits through Square Payments. Works if you're already in Square's ecosystem; clunky if you aren't. The hidden cost: