SMS is not dead — it's just been disciplined
A few years ago, every Indian SMB had a "bulk SMS" panel they used to spray promotional messages from rotating sender IDs. That model is gone — TRAI's DLT framework killed it deliberately, and the result is actually a cleaner channel. Promotional SMS today is harder to do but works better when done right: a registered sender ID, an approved template, an opt-in list, and a Channel that customers actually trust enough to read. The open rate of an SMS still sits north of 95%, and for transactional messages (OTPs, order confirmations, delivery updates) it's the most reliable channel in India bar none.
Proofox's SMS platform is built around the post-DLT reality. We handle DLT principal-entity registration, header (sender ID) approval, content template approval, and ongoing compliance. You get high-deliverability routes on transactional and promotional SMS, real-time delivery reports (DLRs), and an API that integrates with anything from a Shopify store to a Salesforce instance. SMS works alongside our WhatsApp platform and email marketing for true multi-channel orchestration.
When SMS still wins against WhatsApp and email
WhatsApp is the channel of choice for conversational, content-rich, opt-in heavy use cases — but SMS still wins decisively in three buckets: One-Time Passwords (OTP), where the 4-second SMS delivery beats anything else; transactional confirmations to feature-phone users (still ~30% of rural India); and "no-WhatsApp-thanks" segments (older demographics, financial services where SMS records have legal standing). For OTP delivery, our SMS routes consistently hit ~99.5% delivery within 5 seconds, which is the global benchmark.
For promotional use, SMS works particularly well as the last-mile nudge in a multi-channel campaign: the WhatsApp message goes out, the email follows, and the SMS arrives 20 minutes later as the explicit "we're running a sale, here's the link" with brevity that the channel format enforces. It also works as the OTP fallback when WhatsApp delivery fails (carrier issues, account blocks) — most enterprises run SMS as the redundancy channel for any system-critical message flow.
DLT compliance is the moat — and where most SMBs trip
The DLT framework requires every business sending commercial SMS to: register as a Principal Entity (PE) on a DLT operator portal, register Header (sender IDs — exactly 6 characters), register content templates for every message you intend to send, and operate inside the consent + opt-out framework TRAI mandates. Skipping any step results in the message getting blocked at the telco level — and repeated violations get the PE blacklisted across all operators.
We handle the entire DLT layer: PE registration with the right LEI / GST documentation, Header approval (we negotiate naming conflicts with the operator), content templates submitted in the right Variable-Field syntax, and ongoing audits to catch templates drifting out of compliance. This is the part most "cheap bulk SMS" panels skip — and it's why your messages get blocked. Compliance is the product.
How to design SMS campaigns that don't feel like spam
160 characters is a constraint, not a limitation. The senders who treat SMS like a haiku — one clear message, one clear action, one clear sender identity — see 3-5× higher click-through than senders who try to cram a paragraph in. Our copy framework for promotional SMS is three lines: line one is the value proposition, line two is the proof or urgency, line three is the link with a short CTA. Anything more is wasted character budget. We test multiple variants on each campaign and roll out the winning copy at scale.
Timing matters as much as copy. Promotional SMS sent at 11 AM on a weekday outperforms 8 PM by ~22% in our data; transactional and OTP have no time-of-day dependency. For e-commerce flash sales, the optimal send window is the first 90 minutes after the sale goes live (when intent is hottest), with a second nudge 6 hours later to the segment that opened but didn't click. We bake this orchestration into our campaign manager so non-marketing staff can deploy multi-touch SMS without ad-hoc scheduling.
Personalisation in SMS is underused. A SMS that addresses the recipient by first name has ~14% higher CTR than a generic one. A SMS that references the recipient's last purchase or recent browse adds another 8-12%. These are template-variable substitutions — no extra effort once the data plumbing exists. We build the variable feed from your CRM or product catalogue at onboarding so the data is right by send-1, and we test 3-4 variant copies on every recurring campaign to keep the winning template fresh against creative fatigue.
