Ontech USSD Gateway · *388#

Reach every phone in Zambia.
In JSON.

No app. No smartphone. No SIM toolkit. Point a *388*N# shortcode at your HTTPS endpoint and you're on every handset in the country — across MTN, Airtel and Zamtel, through one gateway. We POST JSON, you reply JSON. That's the whole integration.

Start building → Read the API docs
Live sandbox & simulator Self-serve — live the same day One endpoint, three networks
POST your-app.co.zm/ussd
// we send you every session, as JSON
{
  "session_id": "AX-92f1...",
  "msisdn":     "260971234567",
  "user_input": "1",
  "is_new_request": true,
  "shortcode":  "388*100",
  "mno":        "AIRTEL"
}
200 OK your reply
// you answer with the screen + a flag
{
  "response_string":
    "Welcome to Acme\n1. Balance\n2. Pay",
  "continue_session": true
}

// continue_session:false ends the call

Two fields back. No SDK to install, no state machine to run on your side — the gateway keys each dialog by session_id.

Start free → Read the API docs

From zero to a live code

Live in minutes, not months.

01

Sign up & verify

Create a developer account, verify your email, and get your API keys. Build and walk full USSD journeys in the browser simulator — no handset needed.

02

Build free, then go live

Verify your email and a *388*N# code is issued instantly — free, with 120 sessions over a 5-day proof-of-concept. Point your callback URL at it from the portal and you're live. Need more runway? Extend by mobile money from K350/week — no approval queue, ever.

03

Go live

Point the code at your endpoint and dial in. Real traffic flows across all three networks, with per-session logs, latency and success rates in your dashboard.

A quick tour of the integration and the free signup — no sound needed.

See it end to end

From the docs to a live signup, in half a minute.

Watch the whole path — the JSON contract, the free code, the sign-up form — then take it yourself.

Why build here

Everything the integration needs, nothing it doesn't.

One gateway, all operators

MTN, Airtel and Zamtel behind a single endpoint and a single shortcode. Write once; reach every subscriber.

{ }

Plain JSON, no SDK

An HTTP POST in, a JSON reply out. Any language, any framework. If it can serve a webhook, it can run USSD.

Sandbox before you spend

A live simulator walks your menus per network, so you test the whole flow before a shortcode ever goes live.

Metering built in

Per-session logs you can search and export, success-rate and latency dashboards, and usage-based billing — no analytics to wire up.

Free to start
K0 to go live

A live *388*N# code and 120 sessions, issued the moment you verify your email. No card, nothing to pay to go live.

Proof-of-concept — 120 sessions over 5 days, free
Need more? Extend by mobile money from K350/week (up to 1,000 sessions)
Sessions reset each week; days stack. Testing in the sandbox never counts against your balance.

Ship a USSD service this week.

Sign up, wire one webhook, and be live on *388# across Zambia today — free, with 120 sessions to prove it out.

Create your developer account → Integration guide