SMS, email, and TRAI-compliant links for Indian enterprises
DLT header-compliant short links that carriers never block, an SMS API built for scale, and email campaigns that land during business hours. One platform, one API.
Short links that pass TRAI and DLT rules
TRAI requires every commercial SMS in India to carry a whitelisted Header ID, and telecom operators block messages whose URLs aren't registered on the DLT platform. Smler builds compliance into the link itself: your 6-character DLT Header ID sits in the URL structure, the static part is whitelisted once, and the dynamic part changes per message without affecting compliance.
Link anatomy
smler.in/HEADER/
Static part, whitelisted once on DLT
abc123
Dynamic part, unique per link, no re-whitelisting needed
The shortest compliant domain
smler.in is 14 characters including https://. With your header that's 21, leaving maximum room for your message in a 160-character SMS.
Custom domains with headers
Run compliant links on your own brand: yourbrand.link/HEADER/. Full control over branding, same whitelisting model, managed from one dashboard.
Compliance screening built in
Destination URLs are automatically screened against TRAI standards before shortening. Flagged URLs go to manual review, and approved links are marked TRAI-compliant for your campaigns.
Our guarantee: links shortened through our compliance service meet regulatory standards. If a compliant link is ever blocked, we resolve and replace it immediately.
An SMS API that speaks DLT natively
Pass your DLT header in the same call that creates the link. No separate compliance step, no second vendor.
curl --location 'https://app.smler.io/api/v1/short' \
--header 'x-code: YOUR_API_KEY' \
--data '{ "url": "https://example.com/long-url", "dltHeader": "HEADER", "maxLength": 10 }'Email that arrives when people are awake
Timezone-aware sending delivers every email during the recipient's local business hours, not at 3 a.m. their time. Campaigns, transactional email, and the same link analytics you get everywhere else on Smler.
Built for Indian industries
E-commerce
Order updates, delivery notifications, and promotions with compliant tracking links.
Banking & finance
Alerts, loan offers, and investment communication with secure compliant URLs.
Healthcare
Appointment reminders and telemedicine links with patient privacy protection.
Real estate
Listings, site-visit bookings, and project updates with verified links.
Education
Enrollments, exam notifications, and student communication.
Insurance
Policy renewals, claim updates, and quotes with compliant tracking.
Trusted by India's most demanding senders
From airlines to fintech to healthcare: teams that can't afford a broken link.
24/7 Enterprise Support
Round-the-clock support for enterprise customers with dedicated account management, priority resolution, and custom integration assistance. Enterprise customers get a named contact, WhatsApp support, and MSAs reviewed by founders, not a ticket queue.
Get in touch
India link plans
Plans built for Indian SMS and OTT campaigns. All prices in INR.
Free
Small businesses, individual developers testing the platform
15,000 active links/month
Get StartedTeam
Startups and small teams that need more flexibility
75,000 active links/month
Get StartedPopular
Mid-sized businesses with regular SMS and OTT campaigns
1,25,000 active links/month
Get StartedBusiness
Large businesses, telecom providers, enterprises with heavy messaging traffic
2,50,000 active links/month
Get StartedEnterprise
Volume based pricing tailored to your needs
Unlimited active links/month
Contact SalesExisting customers keep their current plans and pricing. Nothing changes.
Building a mobile app? See our deep linking plans.
Smler is also a full deep linking platform: deferred deep linking and install attribution for mobile apps, free at 25,000 attributed installs a month.
Explore the platformFrequently Asked Questions
What does TRAI require for links in SMS?
TRAI requires every commercial SMS in India to carry a whitelisted Header ID tied to a registered Principal Entity. Telecom operators block messages whose URLs aren't registered on the DLT platform. Smler builds the header into the link structure so every link you send is compliant by default.
What is a DLT Header ID?
A DLT Header ID is the 6-character sender code registered on the Distributed Ledger Technology platform. It identifies your entity and must be whitelisted along with your link's static URL part before operators will deliver your messages.
Do I need to whitelist every link?
No. The static part (domain + header) is whitelisted once. The dynamic part changes per link with no impact on compliance. You register once, then every new link you create is automatically compliant.
Can I use my own domain?
Yes. Custom domains with header support are available, for example yourbrand.link/HEADER/. Full control over branding, same whitelisting model, managed from one dashboard.
What if a compliant link gets blocked?
Our guarantee: links shortened through our compliance service meet regulatory standards. If a compliant link is ever blocked, we resolve and replace it immediately.
Do you also send the SMS?
Yes. Smler offers an SMS API with DLT header support built in. Pass your DLT header in the same call that creates the link. No separate compliance step, no second vendor.
Where do I start?
Create a free account to start, or book a call with the founders for enterprise volumes.