Skip to content

SMS Developer API

Transactional messaging, built into your application.

Send alerts, verification messages and customer updates through a documented API designed for real operational workflows.

Built for developers

One clear API for the messages your product needs to send.

Start with a direct integration, then add controls and delivery feedback as the workflow becomes more important.

01

Send with confidence

Submit outbound SMS through a documented API with recipient and message validation before it enters the delivery queue.

02

Estimate before sending

Check the message and destination before committing usage, so your application can make deliberate decisions.

03

Follow asynchronous status

Use callbacks for delivery events and, where needed, HLR lookup results in the systems that need them.

04

Control access

Use API tokens and optional IP restrictions to keep a production integration scoped to the right system.

From request to result

A small API surface with a clear operational lifecycle.

Your application remains in control: validate the destination, estimate usage, submit once and consume delivery events asynchronously.

01 / Authorise

One token per integration.

Keep production systems isolated with revocable credentials and optional source-IP restrictions.

  • Server-side API tokens
  • Optional IP allowlists
  • No credentials in browser code
02 / Estimate

Know the message before sending.

Use the estimate operation to validate recipient and message characteristics before committing the request.

  • Destination validation
  • Message-part awareness
  • Explicit application decision
03 / Queue

Submit without blocking your product.

Accepted messages enter an asynchronous delivery workflow and return a reference your application can retain.

  • Queued processing
  • Stable message reference
  • Transactional workloads
04 / Observe

Bring status back to your system.

Delivery callbacks let your application update its own workflow without repeatedly polling for every message.

  • Webhook callbacks
  • Delivery-state events
  • Audit-friendly processing
05 / Verify

Support identity workflows.

Use SMS for account creation, requested notifications and two-step login challenges with your own expiry and retry policy.

  • Verification codes
  • Operational notifications
  • No unsolicited marketing
06 / Scale

Pay for actual messaging.

The service is usage-based. Destination, route and sender requirements are confirmed before production traffic is enabled.

  • Country-aware routing
  • Sender review where required
  • Transparent usage records

Manage credentials, allowed sources, usage and delivery activity securely from your Silurian workspace.

Good to know. Delivery confirmation and sender behaviour depend on destination country, network and approved sending route. We will help define the appropriate setup before production use.

Developer experience

Integrate SMS into your applications easily.

Send the same authenticated JSON request from your preferred server-side stack. Keep the API token outside browser code and use the estimate operation before sending when price or message length matters.

Open the interactive API reference
curl --request POST 'https://api.silurian.net/sms/v2/send' \
  --user 'YOUR_API_TOKEN:' \
  --header 'Content-Type: application/json' \
  --data '{
    "sender": "YOURBRAND",
    "message": "Your verification code is 123456.",
    "recipients": [{"msisdn": "+34XXXXXXXXX"}]
  }'
Examples use HTTP Basic authentication with the API token as username. The interactive reference also documents header, query-token and short-lived Bearer authentication.

Destination pricing

Know the destination price before your application sends.

Prices below are the current public Silurian rate per SMS part, before VAT. The API estimate operation remains authoritative because message length, destination, route and sender requirements are checked for each request.

DestinationPrice per SMS part
AFAfghanistan 8.3059 CZK
ALAlbania 2.6599 CZK
DZAlgeria 6.7645 CZK
ASAmerican Samoa 2.8387 CZK
ADAndorra 2.0124 CZK
AOAngola 1.8844 CZK
AIAnguilla 3.9138 CZK
AGAntigua & Barbuda 5.3633 CZK
ARArgentina 2.1888 CZK
AMArmenia 5.1338 CZK
AWAruba 3.1890 CZK
AUAustralia 0.7320 CZK
ATAustria 1.2563 CZK
AZAzerbaijan 7.5086 CZK
BSBahamas 1.7660 CZK
BHBahrain 1.0147 CZK
BDBangladesh 11.0986 CZK
BBBarbados 5.8900 CZK
BYBelarus 4.2592 CZK
BEBelgium 1.9569 CZK
BZBelize 5.0275 CZK
BJBenin 5.3609 CZK
BMBermuda 5.8900 CZK
BTBhutan 7.5497 CZK
BOBolivia 5.0009 CZK
BABosnia & Herzegovina 3.4064 CZK
BWBotswana 3.1721 CZK
BRBrazil 0.6064 CZK
IOBritish Indian Ocean Territory 2.7541 CZK
VGBritish Virgin Islands 5.8900 CZK
BNBrunei 1.3602 CZK
BGBulgaria 3.3219 CZK
BFBurkina Faso 4.4211 CZK
BIBurundi 9.5670 CZK
KHCambodia 7.2477 CZK
CMCameroon 5.9431 CZK
CACanada 0.5073 CZK
CVCape Verde 4.6047 CZK
KYCayman Islands 5.4358 CZK
CFCentral African Republic 2.1018 CZK
TDChad 7.0206 CZK
CLChile 0.9881 CZK
CNChina 0.5750 CZK
COColombia 0.4542 CZK
KMComoros 7.6826 CZK
CGCongo - Brazzaville 4.7110 CZK
CDCongo - Kinshasa 6.6679 CZK
CKCook Islands 2.7372 CZK
CRCosta Rica 0.6644 CZK
HRCroatia 3.1286 CZK
CUCuba 1.9786 CZK
ANCuraçao 2.8991 CZK
CWCuraçao 6.6437 CZK
CYCyprus 2.3410 CZK
CZCzechia 1.1959 CZK
CICôte d’Ivoire 6.1605 CZK
DKDenmark 1.1137 CZK
DJDjibouti 2.8266 CZK
DMDominica 4.5661 CZK
DODominican Republic 2.9136 CZK
ECEcuador 6.3055 CZK
EGEgypt 6.7404 CZK
SVEl Salvador 2.7541 CZK
GQEquatorial Guinea 4.3486 CZK
EREritrea 2.2444 CZK
EEEstonia 1.1331 CZK
SZEswatini 3.6963 CZK
ETEthiopia 6.6437 CZK
FKFalkland Islands 1.5800 CZK
FOFaroe Islands 1.1548 CZK
FJFiji 4.0780 CZK
FIFinland 1.0147 CZK
FRFrance 1.1935 CZK
GFFrench Guiana 1.2949 CZK
PFFrench Polynesia 1.9448 CZK
GAGabon 6.4939 CZK
GMGambia 3.7761 CZK
GEGeorgia 2.9136 CZK
DEGermany 2.1042 CZK
GHGhana 5.2908 CZK
GIGibraltar 1.5413 CZK
GRGreece 1.0533 CZK
GLGreenland 0.2730 CZK
GDGrenada 5.4358 CZK
GPGuadeloupe 2.6816 CZK
GUGuam 2.9716 CZK
GTGuatemala 4.7110 CZK
GNGuinea 5.7982 CZK
GWGuinea-Bissau 5.3633 CZK
GYGuyana 5.7982 CZK
HTHaiti 5.8900 CZK
HNHonduras 3.1890 CZK
HKHong Kong SAR China 1.3553 CZK
HUHungary 1.5703 CZK
ISIceland 1.5244 CZK
INIndia 1.7998 CZK
IDIndonesia 9.7361 CZK
IRIran 8.2624 CZK
IQIraq 8.1247 CZK
IEIreland 1.0147 CZK
ILIsrael 4.8318 CZK
ITItaly 1.1548 CZK
JMJamaica 2.8846 CZK
JPJapan 1.2200 CZK
JOJordan 7.5376 CZK
KZKazakhstan 8.1537 CZK
KEKenya 2.8991 CZK
KIKiribati 1.2297 CZK
XKKosovo 6.0398 CZK
KWKuwait 6.9457 CZK
KGKyrgyzstan 6.2064 CZK
LALaos 3.0440 CZK
LVLatvia 1.2080 CZK
LBLebanon 1.1596 CZK
LSLesotho 5.7257 CZK
LRLiberia 4.3486 CZK
LYLibya 7.7019 CZK
LILiechtenstein 0.9639 CZK
LTLithuania 0.9809 CZK
LULuxembourg 2.4642 CZK
MOMacao SAR China 1.0630 CZK
MGMadagascar 9.4365 CZK
MWMalawi 6.3417 CZK
MYMalaysia 3.6238 CZK
MVMaldives 1.5220 CZK
MLMali 5.1459 CZK
MTMalta 1.3239 CZK
MHMarshall Islands 1.3602 CZK
MQMartinique 1.2080 CZK
MRMauritania 5.5083 CZK
MUMauritius 3.7326 CZK
MXMexico 1.7394 CZK
FMMicronesia 1.7829 CZK
MDMoldova 3.2204 CZK
MCMonaco 3.1745 CZK
MNMongolia 7.0979 CZK
MEMontenegro 3.4741 CZK
MSMontserrat 3.0440 CZK
MAMorocco 1.7394 CZK
MZMozambique 3.0440 CZK
MMMyanmar (Burma) 8.9098 CZK
NANamibia 1.0243 CZK
NRNauru 4.0780 CZK
NPNepal 5.9431 CZK
NLNetherlands 1.8433 CZK
NCNew Caledonia 2.8653 CZK
NZNew Zealand 1.0147 CZK
NINicaragua 2.8266 CZK
NENiger 6.7959 CZK
NGNigeria 8.1174 CZK
NUNiue 3.9258 CZK
KPNorth Korea 2.0269 CZK
MKNorth Macedonia 2.1284 CZK
NONorway 0.8697 CZK
OMOman 4.2278 CZK
PKPakistan 8.6972 CZK
PWPalau 2.7662 CZK
PSPalestinian Territories 7.1414 CZK
PAPanama 3.5514 CZK
PGPapua New Guinea 4.6820 CZK
PYParaguay 2.0294 CZK
PEPeru 3.0440 CZK
PHPhilippines 5.1193 CZK
PLPoland 0.6040 CZK
PTPortugal 0.6354 CZK
PRPuerto Rico 2.5246 CZK
QAQatar 2.5367 CZK
RORomania 1.1186 CZK
RURussia 9.7554 CZK
RWRwanda 6.7186 CZK
RERéunion 1.5220 CZK
WSSamoa 3.4064 CZK
SMSan Marino 1.3529 CZK
SASaudi Arabia 4.6385 CZK
SNSenegal 5.7257 CZK
RSSerbia 4.7110 CZK
SCSeychelles 2.6092 CZK
SLSierra Leone 5.6532 CZK
SGSingapore 1.1137 CZK
SXSint Maarten 2.2613 CZK
SKSlovakia 1.2273 CZK
SISlovenia 3.7761 CZK
SBSolomon Islands 2.0294 CZK
SOSomalia 5.1459 CZK
ZASouth Africa 1.1596 CZK
KRSouth Korea 0.4832 CZK
SSSouth Sudan 6.3417 CZK
ESSpain 0.8939 CZK
LKSri Lanka 9.0451 CZK
SHSt. Helena 2.2661 CZK
KNSt. Kitts & Nevis 5.8900 CZK
LCSt. Lucia 5.7257 CZK
PMSt. Pierre & Miquelon 2.8991 CZK
VCSt. Vincent & Grenadines 4.5661 CZK
SDSudan 7.3999 CZK
SRSuriname 5.2908 CZK
SESweden 1.1717 CZK
CHSwitzerland 1.4350 CZK
SYSyria 7.1124 CZK
STSão Tomé & Príncipe 0.5798 CZK
TWTaiwan 1.8119 CZK
TJTajikistan 8.7166 CZK
TZTanzania 6.4939 CZK
THThailand 0.4228 CZK
TLTimor-Leste 3.5514 CZK
TGTogo 4.2037 CZK
TKTokelau 0.6040 CZK
TOTonga 4.0780 CZK
TTTrinidad & Tobago 5.7257 CZK
TNTunisia 6.9578 CZK
TMTurkmenistan 5.2860 CZK
TCTurks & Caicos Islands 3.8509 CZK
TVTuvalu 3.7761 CZK
TRTürkiye 0.1836 CZK
VIU.S. Virgin Islands 0.8915 CZK
UGUganda 6.8249 CZK
UAUkraine 4.2278 CZK
AEUnited Arab Emirates 2.2057 CZK
GBUnited Kingdom 0.9688 CZK
USUnited States 0.5073 CZK
ZZUnknown Region 1.9931 CZK
UYUruguay 2.5681 CZK
UZUzbekistan 9.3616 CZK
VUVanuatu 3.9862 CZK
VEVenezuela 3.1890 CZK
VNVietnam 5.3609 CZK
WFWallis & Futuna 1.7902 CZK
YEYemen 4.1674 CZK
ZMZambia 6.3272 CZK
ZWZimbabwe 4.3945 CZK