Reach every phone in Uganda.
Reliably.
Send SMS at scale over one API — with delivery receipts, local Mobile Money billing, and a free sandbox so you never pay to test.
curl -X POST https://relsms.relworx.com/api/v1/sms/send_message \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"to": "+256 000 000 000",
"message": "Your RelSMS code is 4821."
}'Messaging that reaches everyone
Start with the SMS API and the campaign tools that are live today. USSD is next — so a customer on a ten-year-old handset is never out of reach.
SMS API
Send single or bulk SMS with delivery receipts and detailed analytics. One REST call reaches MTN and Airtel subscribers across Uganda.
Contacts & Campaigns
Not every message needs an engineer. Import an audience, reuse a template and schedule a campaign from the dashboard.
USSD Services
Menus that run on the simplest feature phone — no app, no data. Built on a shared short code, so a SACCO gets an extension instead of a carrier contract.
On the roadmap — not yet available to buy.
One integration. Every subscriber.
We carry the gateway relationship and the infrastructure so you carry none of it.
Call one API
POST to a single endpoint with your key. No per-operator contract, no SMPP bind to manage.
We route to the network
RelSMS holds the gateway integration and routes your message to the subscriber's carrier — MTN or Airtel.
The message is delivered
Your SMS lands on the handset, and credit is settled once delivery is confirmed.
You get confirmation
Delivery receipts stream back to your webhook and dashboard, with history you can audit.
The friction of going direct, removed
Integrating with a mobile operator yourself means contracts, SMPP binds and months of waiting. RelSMS is the one relationship that replaces them.
Pay only for what you send
No monthly fee, no hidden charges. Prices are set in local currency and settled with local payment methods.
- Top up with
- Mtn and Airtel
- Support
- English & Luganda
- Delivery
- MTN · Airtel
- Top up with
- Safaricom
- Support
- English & Swahili
- Delivery
- Billing ready — carrier onboarding in progress
- Top up with
- Tigo, Halopesa, and Airtel
- Support
- Swahili & English
- Delivery
- Billing ready — carrier onboarding in progress
Sandbox testing is always free — sandbox messages are never sent and never billed.
Get to production in an afternoon
A clean REST API documented with OpenAPI, scoped API keys, a free sandbox, and webhooks that just work. Read the docs, grab a key, ship.
{
"id": "9f0a2b7c",
"to": "+256 000 000 000",
"message": "Your RelSMS code is 4821.",
"status": "delivered",
"sandbox": false
}Built for how Uganda actually moves money and messages
From a Kabale SACCO to a Kampala bank — a message that arrives beats an app that was never installed.
Banks & fintech
Transaction alerts, OTP verification and fraud notices, delivered in seconds and confirmed with a receipt.
SACCOs & microfinance
Statement and repayment reminders for every member — no smartphone required.
Agritech
Market prices, input orders and weather advisories, sent to whole groups at once.
Health & NGOs
Appointment reminders and field surveys that reach people without a data bundle.
Retail & logistics
Delivery updates and campaign blasts, scheduled from the dashboard.
Government & utilities
Bill notices and service alerts at national scale.
Ready to move messages forward?
Create an account, test free in the sandbox, and go live once your organization is approved.
New organizations are reviewed before they can send live messages. Sandbox access is immediate.