Comparison

Overview

Company snapshot and where each provider is based.

FieldSMSAPITelesign
What it isA Polish business-messaging platform (a brand of LINK Mobility Poland, part of LINK Mobility Group) offering bulk SMS, MMS, VMS voice, RCS and WhatsApp Business messaging via REST API and a web interface.Digital identity and programmable communications platform offering SMS, RCS, voice, WhatsApp, Viber and email APIs alongside phone verification and fraud-prevention services.
Founded20072005
Ownershippublicprivate
Employees51-200500-1,000
HQ cityGliwiceMarina del Rey
HQ countryPoland (EU)USA
What's the differenceTelesign edges ahead on the overall messaging.dev Score (70 vs 44). SMSAPI is public and headquartered in Gliwice, Poland (EU); Telesign is private and based in Marina del Rey, USA.

Channels

Which messaging channels each provider can send and receive on.

FieldSMSAPITelesign
SMSYesYes
MMSYesNo
RCSYesYes
WhatsAppYesYes
ViberNoYes
Facebook MessengerNoNo
TelegramNoNo
Apple Messages for BusinessNoNo
VoiceYesYes
EmailNoYes
What's the differenceThey share 4 channels. SMSAPI additionally offers MMS, while Telesign additionally offers Viber, Email.

Developer Experience

How quickly a developer can sign up and send a first message.

FieldSMSAPITelesign
Self-service onboardingYesYes
Free developer creditFree test SMS on signupYes
Docs qualityhighhigh
DocumentationOpen ↗Open ↗
SDKsPHP, Python, JavaScript, Java, C#, Go, BashC#, Java, Node.js, PHP, Python, Ruby
Sandbox / test envYesNo
API typesREST, SMTPREST
What's the differenceOn SDKs, SMSAPI adds JavaScript, Go, Bash; Telesign adds Node.js, Ruby; SMSAPI offers Sandbox / test env, while Telesign does not; on API types, SMSAPI adds SMTP.

Data & Compliance

Data residency options and enterprise compliance certifications.

FieldSMSAPITelesign
EU data residencyYesYes
US data residencyNoYes
Choose regionNoNo
GDPRYesYes
ISO 27001YesYes
SOC 2NoYes
HIPAANoYes
What's the differenceTelesign offers US data residency, while SMSAPI does not; Telesign offers SOC 2, while SMSAPI does not; Telesign offers HIPAA, while SMSAPI does not.

Data Retention

How long message content and metadata are stored, and whether that is configurable.

FieldSMSAPITelesign
Retention policyMessages are stored in accordance with applicable law and disclosed only when required by a lawful request; phone numbers are used solely for SMS campaign purposes. No specific retention period is publicly documented. All data is held within the EEA on two redundant data centers in Poland (ATMAN and T-Mobile, over 150 km apart).Customer transaction data is retained for 90 days for operational troubleshooting and billing purposes, with full backups maintained across two separate data centers also kept for 90 days.
What's the differenceSMSAPI: Messages are stored in accordance with applicable law and disclosed only when required by a lawful request; phone numbers are used solely for SMS campaign purposes. No specific retention period is publicly documented. All data is held within the EEA on two redundant data centers in Poland (ATMAN and T-Mobile, over 150 km apart). Telesign: Customer transaction data is retained for 90 days for operational troubleshooting and billing purposes, with full backups maintained across two separate data centers also kept for 90 days.

Pricing & Credits

Pricing model and the cost of a first message.

FieldSMSAPITelesign
Pricing modelPay-as-you-go prepaid credit — pay only for sent messages with no setup fee or contract; minimum top-up around €30.Pay-as-you-go per-message/per-transaction pricing with volume-based enterprise contracts; public per-message rates are not transparently listed.
SMS starting priceFrom ~€0.04 per SMS (international, varies by destination country)Not published
Free developer creditFree test SMS on signupYes
What's the differenceSMSAPI and Telesign are closely matched on pricing & credits — no material differences in the tracked fields.

Reach & Reliability

Global coverage and delivery dependability.

FieldSMSAPITelesign
Countries covered0230
Direct operator connectionsNoYes
Published uptime SLANo published SLANo published SLA
What's the differenceTelesign leads on Countries covered (230 vs 0 for SMSAPI); Telesign offers Direct operator connections, while SMSAPI does not.

Company & Trust

Independent reviews and company profile.

FieldSMSAPITelesign
G2 rating0.04.3
G2 reviews020
Ownershippublicprivate
Employees51-200500-1,000
What's the differenceTelesign leads on G2 rating (4.3 vs 0 for SMSAPI); Telesign leads on G2 reviews (20 vs 0 for SMSAPI).

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