RCS-Box vs SMS.es Business Messenger
RCS-Box
rcs.jetztSMS.es Business Messenger
rcs.esSide by side
| Figure | RCS-Box | SMS.es Business Messenger |
|---|---|---|
| Price from | €49/mo | €20/mo |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Web | Yes | Yes |
| API | Yes | Yes |
| Plans published | 5 | 8 |
| Spec score · RCS Messaging Platforms | 8.6 (#3) | 8.4 (#6) |
| Authentication | Authenticated API calls use a tenant-specific 64-character hexadecimal key through Bearer or X-API-Key headers. | API access uses OAuth2 client credentials, and the page says access tokens are valid for seven days. |
| Company headquarters | LinkedIn lists Railslove's headquarters in Cologne, North Rhine-Westphalia, Germany. | The registered address is Avenida San Crispín 72, Fuensalida, Toledo, Spain. |
| Company legal name | The legal operator identified in the imprint is Railslove GmbH. | SMS.es is the commercial brand of G729 S.L., tax ID B45850724. |
| Company size | LinkedIn lists Railslove in the 11–50 employee range. | LinkedIn lists SMS.es as privately held with 11–50 employees and headquarters in Fuensalida, Madrid. |
| Messaging formats | It supports text with suggestions, rich cards, carousels, XL messages, and automatic video and image unfurling. | RCS supports rich cards, carousels, suggested replies, action buttons, high-resolution images and video, location sharing, and branded sender identity. |
Plans
RCS-Box
- FreeFree
- FreeFree
- Skizze€49 a month
- Atelier€249 a month
- Manufaktur€999 a month
SMS.es Business Messenger
- EmpresaFree
- InicioFree
- SMS Starter€5, paid once
- RCS channel add-on€20 a month
- Conversacional€39 a month
- Omnicanal€79 a month
- EmpresarialPriced on request
- EnterprisePriced on request
In their own words
RCS-Box
RCS-Box is a multi-tenant API for Google RCS Business Messaging, with EU hosting and a German contract partner. It supports text with suggestions, rich cards, carousels, XL messages, and automatic video and image unfurling. Webhooks can deliver incoming messages and opt-in or opt-out events; forwarded webhooks carry an HMAC-SHA256 signature calculated with the tenant API key. Each tenant has a dedicated key and brand-level isolation, plus a configurable country allowlist that defaults to Germany with the +49 prefix. The API manages STOP and START blacklist status per agent. Plans can use standard or newsletter mode, with newsletter billing based on active recipients per month. XL messages are available in all plans from Skizze and count as one conversation. The Free plan costs nothing and includes 100 sessions per calendar month. Skizze costs €49 a month, Atelier €249 a month, and Manufaktur €999 a month. The API is presented for development teams and technology leaders in startups, scale-ups, and enterprise technology units.
SMS.es Business Messenger
SMS.es Business Messenger provides RCS business messaging through a REST API and web interface, with campaign management, webhooks and automatic SMS fallback. Its Campaign API can create, clone, list, retrieve, update, activate, pause and delete campaigns. RCS messages can include rich cards, carousels, suggested replies, action buttons, high-resolution images and video, location sharing and branded sender identity. OAuth2 client credentials provide API access, and tokens are valid for seven days. Configured webhooks report delivered, read and user-reply events in real time. To connect an RCS agent, create it in Google's RCS console and provide its Agent ID, region and webhook URL. RCS requires explicit opt-in, which can be managed with web forms and keyword rules. Before launch, the agent can message only test devices; public availability follows approval by each carrier. The setup guide identifies Android devices using Google Messages and iOS 18 or later as supported test devices. The Inicio tier lists €0.004 per message, and Empresa lists €0.0032 per message; both show free. Empresarial pricing is custom and not specified.