{"slug":"rcs-messaging","title":"RCS Messaging — RBM, Google Business Messages, Apple RCS","tags":["rcs","rbm","business-messaging","google","apple","messaging"],"agent_summary":"RCS (Rich Communication Services) is the GSMA-standardized SMS successor. Supports rich media, suggested replies, branded sender, read receipts, and typing indicators. Business-to-consumer RCS in the US is delivered via Google's RBM (RCS Business Messaging) platform. Apple began native RCS support in iOS 18 (2024-09). Carrier rollout still in progress; treat RCS as a fallback-enhanced channel, not a replacement for SMS/MMS.","trigger_phrases":["RCS messaging","RBM Google","rich communication services","branded business messaging","RCS Business Messaging","Apple RCS iOS 18","RCS vs SMS"],"runnable":false,"markdown":"\n# RCS Messaging\n\nRCS (Rich Communication Services) is the GSMA-standardized successor to SMS/MMS. It's IP-based, supports rich media up to 100 MB, branded sender display, suggested replies, carousels, and read receipts. Business-to-consumer RCS in the US is delivered through Google's RCS Business Messaging (RBM) platform. Apple shipped native RCS support in iOS 18 (released 2024-09).\n\n## RCS vs SMS/MMS — what's different\n\n| Feature | SMS | MMS | RCS |\n|---|---|---|---|\n| Text length | 160 chars / segment | 160 chars + media | Up to 8,000 chars |\n| Media size | None | ~600 KB (carrier-dependent) | Up to 100 MB |\n| Sender display | Phone number | Phone number | Verified brand name + logo |\n| Read receipts | No | No | Yes |\n| Typing indicators | No | No | Yes |\n| Suggested replies | No | No | Yes (up to 11 chips) |\n| Carousels | No | No | Yes (up to 10 cards) |\n| Encryption | None | None | End-to-end (Google-to-Google) |\n| Carrier dependency | Universal | Universal | Carrier + device must support |\n| Fallback | None | None | Auto-falls back to SMS/MMS |\n\n## Where RCS works today (US)\n\n- **Android devices** with Google Messages app — RCS works carrier-side via Jibe (Google's hosted RCS platform). Coverage is universal across major US carriers as of 2023.\n- **iOS 18+** — Apple added native RCS support. Works on all iPhones running iOS 18.0+ when paired with a carrier that has activated RCS for iPhone (T-Mobile, AT&T, Verizon all enabled by late 2024).\n- **Older Android (no Google Messages)** — RCS not available, falls back to SMS.\n- **Older iOS (< 18)** — Falls back to MMS for media, SMS for text.\n\nFor business messaging, assume 50-70% RCS reach in 2026 with rapid growth.\n\n## Two RCS flavors for business\n\n### Carrier RCS / Universal Profile\n\nPerson-to-person RCS, also accessible to businesses via specific carrier integrations. Limited business features, no branded sender. Rare in the US — Google's RBM is dominant.\n\n### Google RCS Business Messaging (RBM)\n\nThe dominant US business RCS channel. Verified by Google, supports branded sender, all rich features. Requires:\n\n- A verified Google Business Profile or registered RBM Agent\n- Brand verification through a Verified Sender process\n- Subscription to RBM via Google or a partner (Twilio, Sinch, Infobip, etc.)\n\nSignalWire does not currently offer first-party RBM. Production RBM today goes through aggregators (Twilio, Sinch, Infobip). When SignalWire ships RBM, it will plug into the same SWML messaging APIs.\n\n## What an RBM message looks like\n\n```json\n{\n \"messageId\": \"msg-12345\",\n \"agent\": \"brands/acme-plumbing\",\n \"to\": \"+13105551234\",\n \"richCard\": {\n \"standaloneCard\": {\n \"cardOrientation\": \"VERTICAL\",\n \"thumbnailImageAlignment\": \"RIGHT\",\n \"cardContent\": {\n \"title\": \"Your appointment is confirmed\",\n \"description\": \"Acme Plumbing — Wednesday at 2 PM\",\n \"media\": {\n \"height\": \"MEDIUM\",\n \"contentInfo\": {\n \"fileUrl\": \"https://cdn.example.com/confirmation.jpg\",\n \"forceRefresh\": false\n }\n },\n \"suggestions\": [\n { \"reply\": { \"text\": \"Reschedule\", \"postbackData\": \"reschedule\" } },\n { \"reply\": { \"text\": \"Cancel\", \"postbackData\": \"cancel\" } },\n { \"action\": { \"text\": \"Call us\", \"postbackData\": \"call\", \"dialAction\": { \"phoneNumber\": \"+12125551111\" } } }\n ]\n }\n }\n }\n}\n```\n\nSuggestions render as tap chips below the message. Postback data fires a webhook to your backend when tapped, similar to a webhook from a button click in an interactive Messenger-style chat.\n\n## Brand verification for RBM\n\nTo send RCS as a verified business, the brand must pass Google's verification:\n\n1. Register the business via Google Business Profile or an RBM partner.\n2. Provide a logo (1024×1024 PNG), brand color, and short description.\n3. Submit a sample message flow showing legitimate use case.\n4. Add DNS-based domain verification on the brand's website.\n5. Wait 3-10 business days for Google approval.\n\nVerified brands get a checkmark icon, branded color in the chat header, and prominent logo. Unverified brands send as plain RCS without branding — still RCS-capable but visually similar to a regular SMS thread.\n\n## Apple RCS specifics\n\nApple's iOS 18 RCS implementation uses the Universal Profile 2.4 specification. Differences from Google RBM:\n\n- No native support for verified business sender branding (as of iOS 18.2)\n- Suggested replies render but with iOS-specific chip styling\n- End-to-end encryption uses Apple's PQ3 protocol (Google uses MLS)\n- Read receipts and typing indicators work cross-platform between iOS and Android RCS\n\niPhone-to-iPhone messages continue to prefer iMessage. RCS kicks in only when the recipient is Android-on-RCS or iMessage is unavailable.\n\n## Fallback behavior\n\nSend to a number that doesn't support RCS and the message auto-falls back:\n\n- Text-only RCS → falls back to SMS\n- RCS with media → falls back to MMS\n- RCS with rich card → falls back to MMS with the title text + image\n- RCS with suggested replies → falls back to MMS, replies become inline text\n\nThis means **never send RCS that depends on a tap-chip for the recipient to take action**. Always include enough information in the text body for SMS-fallback recipients to understand and respond.\n\n## Cost model\n\nRCS pricing through aggregators (typical 2025):\n\n| Message type | Cost per message |\n|---|---|\n| Simple text RCS | $0.008 - $0.015 |\n| Rich card RCS (with media) | $0.015 - $0.025 |\n| Carousel RCS | $0.025 - $0.040 |\n| Inbound RCS (replies) | $0.005 - $0.010 |\n\nMore expensive than SMS but with higher engagement — RCS open rates run 75-90% vs 95% for SMS, but click-through is typically 5-10x higher on RCS.\n\n## When to choose RCS over SMS/MMS\n\n| Use case | RCS | SMS/MMS |\n|---|---|---|\n| OTP / 2FA codes | No (latency, fallback delays) | Yes |\n| Appointment reminders | Yes (rich card with reschedule chip) | Yes (text + link) |\n| Marketing promos | Yes (carousel, branded) | Yes (text + image) |\n| Customer support replies | Yes (typing indicators feel chat-like) | Yes (works universally) |\n| Shipping notifications | Yes (carousel of items) | Yes (text + URL) |\n| Compliance-sensitive (financial, healthcare) | No (encryption story still maturing) | Yes (well-understood compliance posture) |\n\n## A2P 10DLC and RCS\n\nRBM is **separate from 10DLC**. RCS messages do not flow through the 10DLC throughput pool — they have their own RBM throughput limits set by Google. However, the same opt-in/opt-out compliance applies under CTIA and TCPA. STOP/HELP keywords must be respected; opt-in records must be retained.\n\nWhen RCS falls back to SMS/MMS, that fallback traffic **does** consume 10DLC throughput. Plan accordingly.\n\n## Common pitfalls\n\n- **Sending rich content assuming RCS reach** — always design for SMS fallback. Test by disabling RCS on a test phone.\n- **Suggested replies as the only CTA** — replies don't survive fallback. Include the CTA text in the message body.\n- **No opt-in flow for RCS specifically** — opt-in obtained for SMS does not automatically apply to RCS for compliance purposes. Treat RCS as a separate channel for consent records.\n- **Mismatched brand verification across carriers** — Google verification is one process. Aggregator verification may be additional.\n\n## Roadmap notes\n\n- 2024-09: Apple iOS 18 ships RCS support\n- 2024-Q4 to 2025-Q1: Major US carriers enable iPhone RCS interop\n- 2025-2026: RBM Verified Sender expansion; carousel and form features mature\n- Future: SignalWire first-party RBM integration (no firm date as of 2026-05)\n\n## References\n\n- GSMA Universal Profile 2.4 — RCS specification\n- Google RCS Business Messaging — developer documentation\n- Apple iOS 18 release notes — RCS support\n- 3GPP TS 26.114 — IMS multimedia telephony service\n","html":"

RCS Messaging

\n

RCS (Rich Communication Services) is the GSMA-standardized successor to SMS/MMS. It's IP-based, supports rich media up to 100 MB, branded sender display, suggested replies, carousels, and read receipts. Business-to-consumer RCS in the US is delivered through Google's RCS Business Messaging (RBM) platform. Apple shipped native RCS support in iOS 18 (released 2024-09).

\n

RCS vs SMS/MMS — what's different

\n

| Feature | SMS | MMS | RCS |\n|---|---|---|---|\n| Text length | 160 chars / segment | 160 chars + media | Up to 8,000 chars |\n| Media size | None | ~600 KB (carrier-dependent) | Up to 100 MB |\n| Sender display | Phone number | Phone number | Verified brand name + logo |\n| Read receipts | No | No | Yes |\n| Typing indicators | No | No | Yes |\n| Suggested replies | No | No | Yes (up to 11 chips) |\n| Carousels | No | No | Yes (up to 10 cards) |\n| Encryption | None | None | End-to-end (Google-to-Google) |\n| Carrier dependency | Universal | Universal | Carrier + device must support |\n| Fallback | None | None | Auto-falls back to SMS/MMS |

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Where RCS works today (US)

\n\n

For business messaging, assume 50-70% RCS reach in 2026 with rapid growth.

\n

Two RCS flavors for business

\n

Carrier RCS / Universal Profile

\n

Person-to-person RCS, also accessible to businesses via specific carrier integrations. Limited business features, no branded sender. Rare in the US — Google's RBM is dominant.

\n

Google RCS Business Messaging (RBM)

\n

The dominant US business RCS channel. Verified by Google, supports branded sender, all rich features. Requires:

\n\n

SignalWire does not currently offer first-party RBM. Production RBM today goes through aggregators (Twilio, Sinch, Infobip). When SignalWire ships RBM, it will plug into the same SWML messaging APIs.

\n

What an RBM message looks like

\n
{\n  \"messageId\": \"msg-12345\",\n  \"agent\": \"brands/acme-plumbing\",\n  \"to\": \"+13105551234\",\n  \"richCard\": {\n    \"standaloneCard\": {\n      \"cardOrientation\": \"VERTICAL\",\n      \"thumbnailImageAlignment\": \"RIGHT\",\n      \"cardContent\": {\n        \"title\": \"Your appointment is confirmed\",\n        \"description\": \"Acme Plumbing — Wednesday at 2 PM\",\n        \"media\": {\n          \"height\": \"MEDIUM\",\n          \"contentInfo\": {\n            \"fileUrl\": \"https://cdn.example.com/confirmation.jpg\",\n            \"forceRefresh\": false\n          }\n        },\n        \"suggestions\": [\n          { \"reply\": { \"text\": \"Reschedule\", \"postbackData\": \"reschedule\" } },\n          { \"reply\": { \"text\": \"Cancel\", \"postbackData\": \"cancel\" } },\n          { \"action\": { \"text\": \"Call us\", \"postbackData\": \"call\", \"dialAction\": { \"phoneNumber\": \"+12125551111\" } } }\n        ]\n      }\n    }\n  }\n}\n
\n

Suggestions render as tap chips below the message. Postback data fires a webhook to your backend when tapped, similar to a webhook from a button click in an interactive Messenger-style chat.

\n

Brand verification for RBM

\n

To send RCS as a verified business, the brand must pass Google's verification:

\n
    \n
  1. Register the business via Google Business Profile or an RBM partner.
    2. \n
  2. Provide a logo (1024×1024 PNG), brand color, and short description.
    3. \n
  3. Submit a sample message flow showing legitimate use case.
    4. \n
  4. Add DNS-based domain verification on the brand's website.
    5. \n
  5. Wait 3-10 business days for Google approval.
    6. \n
\n

Verified brands get a checkmark icon, branded color in the chat header, and prominent logo. Unverified brands send as plain RCS without branding — still RCS-capable but visually similar to a regular SMS thread.

\n

Apple RCS specifics

\n

Apple's iOS 18 RCS implementation uses the Universal Profile 2.4 specification. Differences from Google RBM:

\n\n

iPhone-to-iPhone messages continue to prefer iMessage. RCS kicks in only when the recipient is Android-on-RCS or iMessage is unavailable.

\n

Fallback behavior

\n

Send to a number that doesn't support RCS and the message auto-falls back:

\n\n

This means never send RCS that depends on a tap-chip for the recipient to take action. Always include enough information in the text body for SMS-fallback recipients to understand and respond.

\n

Cost model

\n

RCS pricing through aggregators (typical 2025):

\n

| Message type | Cost per message |\n|---|---|\n| Simple text RCS | $0.008 - $0.015 |\n| Rich card RCS (with media) | $0.015 - $0.025 |\n| Carousel RCS | $0.025 - $0.040 |\n| Inbound RCS (replies) | $0.005 - $0.010 |

\n

More expensive than SMS but with higher engagement — RCS open rates run 75-90% vs 95% for SMS, but click-through is typically 5-10x higher on RCS.

\n

When to choose RCS over SMS/MMS

\n

| Use case | RCS | SMS/MMS |\n|---|---|---|\n| OTP / 2FA codes | No (latency, fallback delays) | Yes |\n| Appointment reminders | Yes (rich card with reschedule chip) | Yes (text + link) |\n| Marketing promos | Yes (carousel, branded) | Yes (text + image) |\n| Customer support replies | Yes (typing indicators feel chat-like) | Yes (works universally) |\n| Shipping notifications | Yes (carousel of items) | Yes (text + URL) |\n| Compliance-sensitive (financial, healthcare) | No (encryption story still maturing) | Yes (well-understood compliance posture) |

\n

A2P 10DLC and RCS

\n

RBM is separate from 10DLC. RCS messages do not flow through the 10DLC throughput pool — they have their own RBM throughput limits set by Google. However, the same opt-in/opt-out compliance applies under CTIA and TCPA. STOP/HELP keywords must be respected; opt-in records must be retained.

\n

When RCS falls back to SMS/MMS, that fallback traffic does consume 10DLC throughput. Plan accordingly.

\n

Common pitfalls

\n\n

Roadmap notes

\n\n

References

\n\n"}