Comparison
Overview
Company snapshot and where each provider is based.
| Field | GatewayAPI | MessageFlow |
|---|---|---|
| What it is | Danish SMS gateway and messaging platform by ONLINECITY.IO offering SMS, RCS and email APIs with pay-as-you-go pricing and EU data hosting. | Cross-channel messaging platform by Polish CPaaS company Vercom S.A. (Warsaw Stock Exchange listed), providing email, SMS, RCS, mobile push, Viber and WhatsApp through a single REST API and campaign panel. |
| Founded | 1999 | 2005 |
| Ownership | private | public |
| Employees | 11-50 | 51-200 |
| HQ city | Odense | Poznań |
| HQ country | Denmark (EU) | Poland (EU) |
What's the differenceMessageFlow edges ahead on the overall messaging.dev Score (59 vs 54). GatewayAPI is private and headquartered in Odense, Denmark (EU); MessageFlow is public and based in Poznań, Poland (EU).
Channels
Which messaging channels each provider can send and receive on.
| Field | GatewayAPI | MessageFlow |
|---|---|---|
| SMS | Yes | Yes |
| MMS | No | No |
| RCS | Yes | Yes |
| No | Yes | |
| Viber | No | Yes |
| Facebook Messenger | No | No |
| Telegram | No | No |
| Apple Messages for Business | No | No |
| Voice | No | No |
| Yes | Yes |
What's the differenceThey share 3 channels. MessageFlow additionally offers WhatsApp, Viber.
Developer Experience
How quickly a developer can sign up and send a first message.
| Field | GatewayAPI | MessageFlow |
|---|---|---|
| Self-service onboarding | Yes | Yes |
| Free developer credit | Test credits on request | 30-day trial: 100 SMS + 100 emails |
| Docs quality | med | med |
| Documentation | Open ↗ | Open ↗ |
| SDKs | — | — |
| Sandbox / test env | No | Yes |
| API types | REST, SMPP, Email-to-SMS | REST, SMTP |
What's the differenceMessageFlow offers Sandbox / test env, while GatewayAPI does not; on API types, GatewayAPI adds SMPP, Email-to-SMS; MessageFlow adds SMTP.
Data & Compliance
Data residency options and enterprise compliance certifications.
| Field | GatewayAPI | MessageFlow |
|---|---|---|
| EU data residency | Yes | Yes |
| US data residency | No | No |
| Choose region | Yes | No |
| GDPR | Yes | Yes |
| ISO 27001 | No | Yes |
| SOC 2 | No | Yes |
| HIPAA | No | No |
What's the differenceGatewayAPI offers Choose region, while MessageFlow does not; MessageFlow offers ISO 27001, while GatewayAPI does not; MessageFlow offers SOC 2, while GatewayAPI does not.
Data Retention
How long message content and metadata are stored, and whether that is configurable.
| Field | GatewayAPI | MessageFlow |
|---|---|---|
| Retention policy | Message content, sender and recipient are stored in the traffic log for 30 days, after which records are anonymized (message content and full sender deleted, last half of the recipient number removed). An optional "secret" message class skips storage of content, sender and recipient entirely. | All customer data is stated to be stored exclusively on servers within the EEA (Microsoft Azure, AWS). No overall retention period for message content is published; the API docs state sent SMS message data is kept and queryable for 60 days, and the privacy policy retains personal data for the duration of the service agreement plus statutory periods (e.g. accounting records). |
What's the differenceGatewayAPI: Message content, sender and recipient are stored in the traffic log for 30 days, after which records are anonymized (message content and full sender deleted, last half of the recipient number removed). An optional "secret" message class skips storage of content, sender and recipient entirely. MessageFlow: All customer data is stated to be stored exclusively on servers within the EEA (Microsoft Azure, AWS). No overall retention period for message content is published; the API docs state sent SMS message data is kept and queryable for 60 days, and the privacy policy retains personal data for the duration of the service agreement plus statutory periods (e.g. accounting records).
Pricing & Credits
Pricing model and the cost of a first message.
| Field | GatewayAPI | MessageFlow |
|---|---|---|
| Pricing model | Pay-as-you-go per-message pricing with prepaid credit; no monthly subscriptions or fees (except short-code countries), with negotiated discounts for high volumes. | Monthly subscription tiers priced by contact count (Starter from €69/month) with bundled email/SMS volumes and per-unit overages, plus a customizable Mix & Match plan (from €465/month); SMS rates vary by destination country. |
| SMS starting price | From €0.0061 per SMS (standard class, cheapest destination on the public price list; e.g. €0.0401 to Denmark) | Not published (per-country SMS rates shown only in an in-panel calculator; e.g. Grow plan €109/month includes 1,000 SMS) |
| Free developer credit | Test credits on request | 30-day trial: 100 SMS + 100 emails |
What's the differenceGatewayAPI and MessageFlow are closely matched on pricing & credits — no material differences in the tracked fields.
Reach & Reliability
Global coverage and delivery dependability.
| Field | GatewayAPI | MessageFlow |
|---|---|---|
| Countries covered | 200 | 190 |
| Direct operator connections | Yes | Yes |
| Published uptime SLA | No published SLA (99.99%+ historical uptime claimed) | No published SLA (custom SLA available on Enterprise plans) |
What's the differenceGatewayAPI leads on Countries covered (200 vs 190 for MessageFlow).
Company & Trust
Independent reviews and company profile.
| Field | GatewayAPI | MessageFlow |
|---|---|---|
| G2 rating | 4.9 | 4.9 |
| G2 reviews | 7 | 11 |
| Ownership | private | public |
| Employees | 11-50 | 51-200 |
What's the differenceMessageFlow leads on G2 reviews (11 vs 7 for GatewayAPI).
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