Messaging API
Send codes and alerts with one request. The parts and the price come back in the answer, the receipt by webhook.
About the APIRoute trust Every route tested on real phones
Send the text.
Know it arrived.
An SMS API for verification codes, alerts and campaigns. We check every route against real phones, so a receipt that says delivered is one you can trust.
Free test credits. No card, no monthly fee, no contract.
- REST API and SMPP 3.4
- Public prices for every country
- Signed delivery webhooks
Campaigns
Send to a whole list from one CSV, schedule it, and see who clicked. Duplicates and opted out numbers are skipped.
About campaigns
SMPP and wholesale
Bind your platform over SMPP 3.4 with TLS. The same routes, prices and reports as the API.
About SMPP
Verify Soon
Verification codes by Telegram first and SMS second, from one call. Coming soon to the console.
Ask for early accessAnalytics
Know how every message did
Delivery rate, time to the handset and spend on one screen, and every message traced from the request to the receipt.
Overview
Messages18,40619,212 parts billed
Delivery rate97.8%398 not delivered
Time to handset2.6 smedian
Spend538.21 USDBalance 1,204.50
Messages per dayDelivered Undelivered Failed
17 Oct23 Oct30 Oct
Time to handsetshare of messages
0 s5 s10 s+
- Delivery rate and time to handset
- Spend and balance, day by day
- A timeline for every message
- Campaign reports with clicks
- Delivery and speed per destination
- Export to CSV
Delivery quality
Delivered should mean delivered
Some routes report a message delivered whether or not a phone ever buzzed. We test our routes with real phones and watch every receipt on live traffic, so the delivery rate you see is one you can trust.
- Routes tested with real phones
- Receipts watched on live traffic
- Quality routing on trusted receipts
- Our team alerted when a route slips
Routing ruleActive
Product: Standard
Country: United Kingdom
Any sender
Route
PriorityWeightedLeast costBest quality
- 1Northline · SMPPbuy 0.0180
- 2Tern Messaging · HTTPbuy 0.0165
- 3Upstream · Standardbuy 0.0210
Allow selling at a loss
Route tester+44 7700 900123 · Acme · attempt 1
DestinationUnited Kingdom, 234 30
Sell price0.0290
RuleUK, best quality
| Target | Buy | Margin | Recent delivery | Result |
|---|---|---|---|---|
| Northline · SMPP | 0.0180 | 0.0110 | 98.2% | Picked |
| Upstream · Standard | 0.0210 | 0.0080 | 97.9% | Next on retry |
| Tern Messaging · HTTP | 0.0165 | 0.0125 | 91.4% | Lower quality |
| Harbour SMS · SMPP | 0.0310 | −0.0020 | 96.8% | Skipped, at a loss |
Routing, for partners
Route every destination your way
Partners run their own routing in their console: rules by client, product, country, network or number, with a route tester that shows what will happen before a message goes out.
- Priority and weighted split
- Least cost and best quality
- Failover on every retry
- No selling at a loss
- A route tester with margins
- A log of every change
Try it here
See the price before you send
Type, or change the number, and watch the parts and the price follow. Press send and the receipt comes back the way it does in the console.
Send a messageSample prices
GSM · 1 part51 / 160
Type, or change the number, and watch the parts and the price follow.
0.0290 USDUnited Kingdom, 0.0290 per part
+44 7700 900123Draft
Your Acme code is 482913. It expires in 10 minutes.
- Accepted and chargedPrice fixed when the API answers
- Sent to the networkThe operator answers with an ID
- Delivered to the handsetReceipt from the operator
- Webhook sent to your endpointmessage.delivered, signed
Press send to watch the receipt come back.
Delivered should mean
a phone buzzed.
So we test our routes
on real phones, and stop
trusting the ones that lie.
How it works
Three steps to your first delivered code
Create an account
Verify your own phone number and send to it on free test credits. No card needed.
Send with one request
Make an API key and post a message. The answer carries the parts and the price.
Go live
Register your sender and add credits by card, PayPal or bank transfer. Then send to anyone.
For developers
One request in.
The receipt comes back.
- Plain statuses: queued, sent, delivered, undelivered, failed, with the operator's error code.
- Signed webhooks for every receipt, retried automatically if your endpoint is down.
- Idempotency keys, so a retry never sends or charges twice.
curl https://app.siellabs.com/v1/messages \
-H "Authorization: Bearer $API_KEY" \
-H "Content-Type: application/json" \
-d '{"to": "+447700900123", "from": "Acme",
"body": "Your Acme code is 482913."}'Response 201
{
"id": "6f1c3d2a-7c1e-4e0b-9d2f-2b1f4b9a2e10",
"status": "queued",
"to": "+447700900123",
"from": "Acme",
"encoding": "gsm7",
"segments": 1,
"price_micros": 29000,
"country": "GB"
}const res = await fetch("https://app.siellabs.com/v1/messages", {
method: "POST",
headers: {
Authorization: `Bearer ${process.env.API_KEY}`,
"Content-Type": "application/json",
},
body: JSON.stringify({
to: "+447700900123",
from: "Acme",
body: "Your Acme code is 482913.",
}),
});
const message = await res.json(); // { id, status: "queued", segments, price_micros, … }import os, requests
r = requests.post(
"https://app.siellabs.com/v1/messages",
headers={"Authorization": f"Bearer {os.environ['API_KEY']}"},
json={"to": "+447700900123", "from": "Acme",
"body": "Your Acme code is 482913."},
)
message = r.json() # {"id": ..., "status": "queued", "segments": 1, ...}$ch = curl_init("https://app.siellabs.com/v1/messages");
curl_setopt_array($ch, [
CURLOPT_POST => true,
CURLOPT_RETURNTRANSFER => true,
CURLOPT_HTTPHEADER => [
"Authorization: Bearer " . getenv("API_KEY"),
"Content-Type: application/json",
],
CURLOPT_POSTFIELDS => json_encode([
"to" => "+447700900123", "from" => "Acme",
"body" => "Your Acme code is 482913.",
]),
]);
$message = json_decode(curl_exec($ch), true);body, _ := json.Marshal(map[string]string{
"to": "+447700900123", "from": "Acme",
"body": "Your Acme code is 482913.",
})
req, _ := http.NewRequest("POST", "https://app.siellabs.com/v1/messages", bytes.NewReader(body))
req.Header.Set("Authorization", "Bearer "+os.Getenv("API_KEY"))
req.Header.Set("Content-Type", "application/json")
res, err := http.DefaultClient.Do(req)The console
What support sees when a customer says no code came
Each message opens to its text, its parts with the operator's own IDs and receipts, the time to the handset, and the webhooks that told your system about it.
+44 7700 900318Delivered in 3.6 s
Hi Dana, your Acme order 30638 is packed and leaves our warehouse today. It should reach you on Thursday between 9:00 and 13:00. Track it any time at acme.example/t/30638, where you can also change the time.
- Accepted and chargedThrough the API, key ending 7f3a14:02:08.512
- Handed to the operator2 parts, each with the operator's ID14:02:08.540
- Part 1 deliveredDELIVRD from the operator14:02:11.902
- Part 2 deliveredDELIVRD from the operator14:02:12.118
- Webhook sent to your endpointmessage.delivered, answered 200 in 86 ms14:02:12.204
| # | Operator ID | Receipt | Error | Time to receipt | Price |
|---|---|---|---|---|---|
| 1 | 4f0e9c21b7 | DELIVRD | None | 3.4 s | 0.0290 |
| 2 | 4f0e9c21b8 | DELIVRD | None | 3.6 s | 0.0290 |
Security
Built so a leak has nothing to find
Encrypted everywhere
Message text and secrets are encrypted in transit and at rest, and the API and SMPP connections use TLS.
Content on a need to know basis
Only staff whose role requires it can open message text, every access is recorded, and old text is erased after the retention period.
Two factor sign in
Protect your console with an authenticator app and recovery codes, see where you are signed in, and sign out other sessions.
Pricing
Pay per part, nothing else
No monthly fee, no minimum, no contract. Every destination has a public price, and changes carry a date you see ahead of time.
Pay as you go
Per part from the price list
Prepaid credits, spent as you send.
- Free test credits to start
- A public price for every country
- Card, PayPal or bank transfer
- Refunds for parts never accepted
Volume
Custom rate sheet
For a few hundred thousand messages a month and up.
- Rates by MCC and MNC
- Postpaid with a credit limit
- SMPP 3.4 over TLS
- Price changes dated ahead
Partner
Your prices your brand
Run an SMS business on our platform.
- Your console at your domain
- Your clients, staff and routes
- Us as your upstream
- Partners of your own
a month, at the local price—
| Country | Local, USD | International | Networks |
|---|---|---|---|
Questions
What people ask first
Something else? A person who runs the routes answers by email within one business day.
What do I need to send my first message?
An account, a sender ID and credits. Sign up, verify one of your own phone numbers as a test number, and send to it right away on the free test credits. Register a sender ID for your brand; once it is approved and you have added credits, you can send to anyone.
How is it priced?
Per message part, from a prepaid balance. No monthly fee, no minimum, no contract. Every country has a price on the public price list, and the API tells you the price of each message when it accepts it.
Which countries can I send to?
Every destination on the price list. Traffic goes over direct operator connections where we have them and over vetted wholesale partners elsewhere. The price list in the console shows each destination's recent delivery rate and time to handset.
How do you know a message was really delivered?
Operators send a receipt for each part, and we test our routes with real phones and watch receipts on live traffic. Routes whose receipts do not match what phones receive stop counting in quality routing, and our team is alerted.
Can I connect over SMPP instead of the API?
Yes. Create an SMPP login in the console and bind with SMPP 3.4 over TLS. Submits go through the same validation, pricing and routing as the API, and receipts come back as deliver_sm.
What reports and analytics do I get?
A dashboard with your delivery rate, time to handset, spend and daily volume, a log of every message with its timeline and receipts, campaign reports with clicks, and a price list with each destination's delivery rate and speed. Lists export to CSV.
Is there a console for people who do not write code?
Yes. A composer that shows the part count and the price before you send, campaigns from a pasted list or a CSV with templates and contacts, sender ID registration, API keys, webhooks and billing.
Do you send verification codes?
Yes, as ordinary messages through the API today. Verify, which sends a code by Telegram first and SMS second and checks it for you, is coming soon to the console. Write to us for early access.
Who can read message content?
Message text is encrypted in transit and at rest. Only staff whose role requires it can open it, every access is recorded, and old text is erased after the retention period.
Send a code to your own phone in five minutes
Sign up, verify your number and send to it on free test credits. Add a sender and credits when you are ready for real traffic.
Free test credits. No card, no monthly fee, no contract.
