CS (Rich Communication Services) is the carrier-standard successor to SMS, and RCS Business Messaging (RBM) is its enterprise form: a verified, branded sender delivering rich cards, carousels, suggested replies and actions, and read receipts straight to the phone's native Messages app — no app install required. In 2026, with support on Android since 2019 and on iPhone since iOS 18, RBM is the upgrade layer over SMS, with SMS remaining the universal fallback where RCS is unavailable.
Short on time? See the answers on RCS for business, what RCS is, and RCS vs SMS. This guide ties them together end to end.
What RCS is — and what RBM adds
RCS is a GSMA-standard protocol carried by mobile operators and rendered in the native Messages app. Where SMS is 160 characters of plain text from an alphanumeric sender, RBM adds a verified brand identity (name, logo, colour, checkmark), rich media, interactive buttons, and delivery and read receipts — an app-like experience without an app. See what is rcs business messaging.
How RBM works
A business is verified through the RCS ecosystem, then sends messages via a provider's API. The message is delivered over the RCS network to capable devices; where a device or network cannot receive RCS, the campaign falls back to SMS. Capability checks let you know, per recipient, whether RCS is available before you send — which is what makes reliable fallback possible. See sms fallback strategy.
Reach in 2026
RCS is native in Google Messages on Android (since 2019) and, significantly, supported on iPhone since iOS 18 (2024), which expanded addressable reach considerably. Coverage still varies by market, carrier and device, so RCS is best treated as the rich upgrade for capable users with SMS beneath it for everyone else — not a universal replacement yet.
RCS vs SMS vs WhatsApp
| Attribute | SMS | RCS (RBM) | |
|---|---|---|---|
| Install needed | No | No (native inbox) | Yes (app) |
| Branding | Sender ID | Verified brand + logo | Verified business name |
| Rich content | Text only | Cards, carousels, actions | Media, buttons, catalogue |
| Reach | Universal | Capable devices + carriers | 2B+ app users |
| Best role | Universal fallback | Branded rich notifications | Conversational + marketing |
The three are complementary. Use SMS for universal reach and OTP, RCS for branded rich notifications in the default inbox, and WhatsApp for opted-in conversational and marketing threads — and orchestrate them behind one API. See our channel decision guide and the answer on WhatsApp vs RCS for business.
Where RBM shines
- Order and delivery updates with a live card, image and one-tap tracking.
- Appointment reminders with confirm/reschedule buttons in the thread.
- Branded promotions with carousels and suggested actions.
- Authentication and alerts where a verified sender raises trust.
- Conversational support with rich replies, backed by SMS fallback.
BroadNet delivers RCS Messaging with automatic SMS fallback behind one omnichannel API, so you get RBM's richness on capable devices and guaranteed SMS reach everywhere else — from a single integration.
Getting started with RBM
Verify your brand through the RCS ecosystem, design your agent and message templates, wire capability checks and SMS fallback, and test on real devices across your target markets. Follow the same consent and content rules as other channels. See rcs for business and what is verified sender.
Frequently asked questions
What is the difference between RCS and RCS Business Messaging?
RCS is the underlying carrier protocol that upgrades person-to-person messaging in the native inbox. RCS Business Messaging (RBM) is the enterprise layer on top of it: verified branded senders, rich cards and buttons, and delivery and read receipts for businesses to message customers. When people say 'RCS for business,' they mean RBM.
Does RCS work on iPhone?
Yes. Apple added RCS support to iPhone in iOS 18 (2024), so RCS messages can be delivered to updated iPhones as well as Android devices. Coverage still depends on carrier and device support, so treat RCS as the rich upgrade for capable users and keep SMS as the universal fallback.
Do I still need SMS if I use RCS?
Yes. RCS reach, while growing, is not universal — it depends on device, carrier and network. SMS reaches any handset, so it remains the fallback that guarantees delivery when RCS is unavailable. The standard pattern is RCS first for richness, SMS underneath for reach, orchestrated automatically.
Is RCS more expensive than SMS?
RCS is typically priced per message or session and differs from SMS's per-segment model. Whether it costs more depends on the message and market, but RCS often delivers more value per interaction through branding and interactivity. Model your traffic and use RCS where its richness earns its price, with SMS as the efficient fallback.
References
- GSMA — RCS and Universal Profile: gsma.com
- Apple — iOS 18 RCS support (2024): apple.com
- BroadNet — Answers: RCS for business, RCS vs SMS, SMS fallback strategy.