What Is RCS Messaging?
RCS (Rich Communication Services) is a messaging protocol built into the default messaging app on smartphones. It replaces SMS with branded, interactive messages, verified sender profiles, high-resolution media up to 100 MB, product carousels, and tappable action buttons, delivered directly to the recipient’s standard messaging inbox, with no app download required.
Where SMS shows only a phone number and plain text, RCS displays your verified business name, logo, and brand colours alongside interactive elements that behave more like a mobile app than a text message. For devices that do not yet support RCS, messages fall back to standard SMS automatically.
If you have been running SMS campaigns for your brand, you already know the limitations. 160 characters. No branding. No images worth looking at. No way for a customer to tap a button and buy directly from the message. Your brand’s carefully crafted identity gets reduced to a grey bubble from an unknown number.
RCS changes all of that. It is the biggest upgrade to business messaging since SMS was invented in 1992, and it is now reaching the scale where brands that ignore it are leaving money on the table.
RCS vs SMS vs MMS: Feature Comparison
| Feature | SMS | MMS | RCS |
|---|---|---|---|
| Character limit | 160 | 1,600 | 8,000+ |
| Images | None | Low-res, compressed | High-res, up to 100 MB |
| Video | None | Short, heavily compressed | Full HD video |
| Branding | None, shows phone number | None | Verified sender name, logo, colours |
| Interactivity | None | None | Buttons, carousels, suggested replies |
| Read receipts | None | None | Yes |
| Typing indicators | None | None | Yes |
| Fallback | N/A | SMS | SMS (automatic) |
The fallback mechanism is particularly important. When you send an RCS message to a device that does not support it, the message automatically degrades to SMS. Your campaign still reaches everyone, RCS-capable devices get the rich experience, and everyone else gets a standard text.
Why RCS Matters Now
RCS reached critical mass in 2024 because Apple finally added support, making it viable for brands to reach virtually every modern smartphone without requiring a separate app, and major marketing platforms responded by shipping native integrations.
RCS has been in development since 2007, but two things happened recently that changed its trajectory entirely.
First, Apple added RCS support to iPhones with iOS 18 in September 2024. Before this, RCS was Android-only, which limited its reach significantly. With Apple on board, RCS now reaches virtually every modern smartphone, the protocol is projected to have 3.8 billion active users by the end of 2026. Google had been pushing carriers to adopt RCS for years, and Apple’s support was the missing piece that made it viable for brand adoption at scale. Adoption increased 550% through 2024 alone.
Second, major marketing platforms have started building native RCS support. Klaviyo launched RCS messaging capabilities, allowing brands to send rich, branded messages through the same platform they already use for email and SMS. Sinch, Twilio, Infobip, and other CPaaS providers have expanded their RCS offerings. The infrastructure is no longer experimental, it is production-ready.
It is worth noting that the UK has a particular head start here. Virgin Trains and Vodafone launched the world’s first commercial RCS Business Messaging campaign back in August 2018, and UK carriers have been supporting the protocol for years.
The Numbers That Matter
Early adoption data from brands running RCS campaigns is compelling:
- Up to 35 times higher engagement compared to SMS, according to Google’s own case studies with enterprise brands.
- Open rates above 90%, partly because messages appear richer and more trustworthy in the native messaging app. 88% of consumers say they trust messages more when they see a verified company badge.
- Conversion rates 20 to 60% higher than equivalent SMS campaigns, driven by interactive elements like product carousels and one-tap purchase buttons. Brands saw 60 to 70% higher conversion rates with rich cards versus MMS in A/B holiday tests.
- 3 to 5 times higher click-through rates on RCS messages with action buttons versus SMS with shortened URLs.
These are not theoretical projections. Brands like Subway, Vodafone, and several major airlines have reported these figures from live RCS campaigns. In the US alone, one billion RCS messages are now sent daily.
What RCS Looks Like in Practice
In practice, an RCS message from your brand looks and behaves more like a branded app experience than a text: verified sender identity at the top, swipeable product carousels, tappable action buttons, and high-resolution media, all inside the recipient’s default messaging app.
When a customer receives an RCS message from your brand, they see your verified business name, logo, and brand colours at the top of the conversation, not a random phone number. This is controlled through what is called an RCS Agent, a verified business identity registered with Google and local carriers.
From there, the message itself can include:
Product carousels. Swipeable product cards with images, descriptions, and “Buy Now” buttons. A fashion retailer can showcase five new arrivals in a single message, with each card linking directly to checkout.
Suggested replies and actions. Instead of asking customers to type a response, you present tappable options: “Track my order”, “Speak to an agent”, “Browse sale items”. This reduces friction and increases response rates.
Rich media. High-resolution images that actually look good, not the compressed, grainy images MMS produces. Video content that plays inline. GIFs that render properly.
Location sharing and maps. “Find your nearest store” with an embedded map. Useful for retail, hospitality, and service businesses.
Payment integration. Some RCS implementations support in-message payments, turning a marketing message into a complete transaction without the customer ever leaving their messaging app.
Getting Started: The Practical Path
If your brand is already running SMS campaigns through a platform like Klaviyo, the path to RCS is relatively straightforward. Here is what the process looks like.
1. Choose a Platform with RCS Support
Klaviyo now offers native RCS support, which means brands already using it for CRM and marketing automation can add RCS without switching platforms. Other platforms with RCS capabilities include Sinch, Twilio, Infobip, and Vonage.
2. Register Your RCS Agent
This is the most involved step. You need to create a verified business identity, your RCS Agent, which includes your brand name, logo (224×224px), cover image (1440×448px), brand colour, description, and contact details. This gets submitted to Google and your local carriers for verification.
In the UK, this includes a third-party brand verification step through Brand Assure. The carrier review process typically takes four or more weeks, so plan accordingly.
3. Test Before You Launch
Most platforms provide a test mode where you can send RCS messages to approved numbers before going live. Use this to verify how your branding renders, test interactive elements, and confirm the SMS fallback works correctly.
4. Design for RCS, Not Just SMS
This is where many brands stumble. They take their existing SMS campaigns and simply add an image. That misses the point entirely. RCS campaigns should be designed from scratch to take advantage of interactivity: carousels for product discovery, suggested replies for quick engagement, branded experiences that reinforce your identity.
Where RCS Fits in Your Messaging Strategy
RCS does not replace your existing channels, it enhances one of them. Your email campaigns, WhatsApp Business messages, and push notifications all continue to serve their purpose. RCS specifically upgrades the SMS channel you are already using.
The smart approach is to run RCS and SMS in parallel. Your platform handles the routing: RCS-capable devices receive the rich version, and everyone else receives SMS. Over time, as device support reaches near-universal coverage, the proportion of messages delivered as RCS will increase.
For brands already investing in digital strategy and customer experience, RCS is a natural extension. It brings the branded, interactive experience customers expect from your website and app into the messaging channel where they are most responsive.
Challenges to Consider
The main practical challenges with RCS are the carrier registration timeline (typically four to six weeks in the UK), a higher per-message cost than SMS, and the additional creative effort required to design effective rich campaigns, though the SMS fallback means incomplete device coverage is handled automatically.
RCS is not without its complications. Being realistic about these helps you plan properly.
Carrier approval takes time. Registration and verification can take four to six weeks, and requirements vary by country. If you are operating across multiple markets, you need a separate RCS Agent registration for each.
Not every device supports it yet. While Apple’s iOS 18 adoption is high, older iPhones and some budget Android devices still lack RCS support. The SMS fallback handles this, but it means not every recipient gets the rich experience immediately.
Cost is higher than SMS. RCS messages typically cost more per message than standard SMS. The higher engagement and conversion rates generally justify the premium, but you need to factor this into your campaign economics.
Content requires more effort. Designing effective RCS campaigns with carousels, images, and interactive elements takes more creative effort than writing a 160-character text. Budget for this in your marketing workflow.
On the positive side, security is improving rapidly. The GSMA adopted Universal Profile v3.0 in March 2025, adding end-to-end encryption via the MLS protocol. This addresses one of the earlier criticisms of RCS and puts it on par with WhatsApp and iMessage for message security.
The Bottom Line
RCS is not a future technology, it is available now, and brands that adopt early are seeing measurably better results from their messaging campaigns. The combination of Apple’s support, platform readiness from providers like Klaviyo, and growing carrier coverage means the window for early-mover advantage is open but closing.
If you are already running SMS campaigns, adding RCS is an incremental upgrade with outsized returns. If you are building a new CRM and automation stack, RCS should be on the requirements list from day one.
The brands that will win in messaging over the next two years are the ones that stop treating it as a plain-text channel and start treating it as a rich, branded experience. RCS makes that possible without asking your customers to change a single thing about how they communicate.