Klaviyo Spring 2026: Composer AI, RCS Messaging, and What's Worth Your Attention

Most “AI-powered” email updates in 2026 amount to a subject line suggester and a call it a day. Klaviyo’s Spring 2026 release is different in scale. On March 24, 2026, the company announced Composer — an agentic AI that builds entire marketing campaigns from a single text prompt — alongside more than 75 other platform updates including RCS Business Messaging, Customer Agent expansions, and multi-email profile support.

Full release notes are at klaviyo.com/whats-new. What’s actually worth your attention, what the limitations are, and whether any of it changes the calculus for ecommerce brands evaluating Klaviyo.

Composer: AI That Builds Full Campaigns

Composer is Klaviyo’s biggest launch. It is an agentic AI — meaning it does not just suggest, it executes — that takes a plain-language brief and builds a complete campaign: subject line, body copy, images, audience segment, and send logic, all from a single prompt.

Type something like “create a spring re-engagement campaign for customers who haven’t bought in 90 days” and Composer produces a ready-to-review campaign across email and SMS. It adapts tone and format for each channel automatically rather than just copy-pasting the same message.

What makes this more than a novelty is what the model is trained on. Klaviyo has 193,000 customers and 14+ years of performance data across billions of consumer interactions. Composer’s outputs are shaped by what has actually worked across that dataset, not generic best-practice templates. A win-back sequence built by Composer should be tuned to win-back norms across real ecommerce purchase patterns, not marketing textbook theory.

Nothing goes live without human review. Every campaign Composer builds sits in a staging queue until you approve, edit, or discard it. This matters: the pitch is speed and a strong starting point, not fully autonomous sends.

The weakness here is access. A feature in private beta is not a feature you have. For the majority of Klaviyo customers, Composer is marketing material for now, not a working tool. It also currently covers email and SMS only — mobile push and WhatsApp support are described as “on the way” with no firm date. Brands running omnichannel campaigns will need to wait or manually adapt Composer drafts for other channels.

RCS Business Messaging: Now Generally Available

Rich Communication Services (RCS) messaging graduated to general availability in Klaviyo this quarter. RCS delivers interactive, branded messages inside the native messaging app on Android — carousels, suggested replies, high-resolution images, branded sender identity. It is effectively what SMS should have been if carriers had not spent two decades ignoring UX.

RCS in Klaviyo works within your existing SMS flows. You do not set up a separate channel; eligible messages are automatically upgraded to RCS format on supported devices, and fall back to standard SMS on devices that do not support it. This means no new workflow architecture required — you just benefit from richer formatting where available.

The catch is reach. RCS is Android-only. Apple added RCS support in iOS 18, but the rich business messaging features that make RCS useful for marketing (interactive carousels, verified sender branding) are still limited primarily to Android. If your customer base skews iPhone, the practical impact is muted for now. Google and Apple are still ironing out interoperability standards at the carrier level.

Customer Agent: More Channels, More Control

Klaviyo’s Customer Agent — their AI-powered customer service assistant — expanded significantly this quarter. It now handles conversations across email and WhatsApp in addition to the existing chat and SMS support. More practically, you can now configure exactly how the agent communicates: tone (professional, friendly, or casual), decision-making rules, and escalation triggers that hand off to a human rep with full conversation context.

This is the configuration that has been missing since Customer Agent launched. An agent that cannot be tuned to your brand’s voice is a liability, not a feature. Now you can define guardrails, limit which topics the agent addresses, and set specific conditions (order value threshold, complaint type, sentiment trigger) that automatically escalate to your support team.

The practical value depends entirely on your support volume and ticket complexity. Brands handling thousands of “where is my order” queries per month will see immediate time savings. Brands with complex, high-touch support interactions will still need humans involved for most conversations — the agent handles the long tail, not the nuanced cases.

Multi-Email Profiles and Personalization Updates

Klaviyo profiles can now store up to five email addresses, each with independent consent status, suppression history, and engagement tracking. In practice this solves a real problem: customers who have multiple email addresses (personal, work, Gmail, Apple relay) often create duplicate profiles that fragment their purchase history and break segmentation.

A unified profile with all a customer’s addresses in one place means cleaner segmentation data, fewer duplicates to merge manually, and a more accurate view of each customer’s behavior. The consent independence is important for compliance — suppressing one address does not suppress others unless you explicitly do so.

Next Best Product (NBP) recommendations — Klaviyo’s AI-powered product suggestion engine — now work across SMS, RCS, and WhatsApp in addition to email. Personalized product recommendations in text channels have higher open-rate context than email (SMS open rates consistently run 90%+), so extending NBP to these channels is a meaningful improvement for product discovery campaigns.

Who These Updates Are Actually For

Composer, Customer Agent, and NBP expansion are all most valuable at scale. Brands with under 5,000 contacts and simple email flows will not see meaningful ROI from AI campaign generation — the time savings are not significant when campaigns are small. The data-driven intelligence in Composer also works better with richer behavioral data, which means larger, more established Klaviyo accounts will get better outputs than new accounts with thin history.

RCS is most valuable for brands with significant Android customer bases and existing SMS programs. If you are not already doing SMS marketing, RCS is not a reason to start — there are bigger fundamentals to address first.

Multi-email profiles and Customer Agent are broadly useful, regardless of account size. Cleaner data and consistent customer service improve outcomes at every scale.

Klaviyo has always been the ecommerce email platform for brands that have outgrown basic tools. If you are running a serious ecommerce operation — Shopify or WooCommerce, meaningful email revenue, multiple product lines — the Spring 2026 updates give you genuinely useful new tools.

If you are a creator, a service business, or a B2B company, very little in this release is relevant to your use case. Klaviyo’s ecommerce focus is both its strength and its narrowness.

The Pricing Reality

Every Klaviyo update conversation needs to include pricing, because the platform is expensive relative to most alternatives and gets more expensive quickly as your list grows.

Current pricing starts at $20/month for up to 500 active profiles on the Email plan, rising to approximately $30/month at 1,000 profiles, $150/month at 10,000 profiles, and $720/month at 50,000 profiles. The Email + SMS plan starts at $35/month for 500 subscribers. There is a free tier capped at 250 active profiles and 500 email sends per month — useful for testing, not for running a real business.

Critically, Klaviyo changed its billing model in February 2025. Pricing is now based on all active profiles in your account, not just contacts you email each month. If you have a list with a large inactive segment you have not cleaned, you are paying for it whether or not you mail to it.

For brands generating strong email revenue, the pricing is justifiable — Klaviyo’s segmentation, automation depth, and now AI features are difficult to match elsewhere. For brands still finding their footing with email, the cost is steep. Omnisend covers most ecommerce-focused email features at a lower price point. Mailchimp remains an option for brands that want a lighter ecommerce integration without Klaviyo’s price scale.

See our full Klaviyo pricing breakdown and our Klaviyo vs Mailchimp comparison for deeper cost analysis. If you are evaluating options at the ecommerce level, our best email marketing for ecommerce guide covers the full competitive landscape.

Forrester Recognition

Klaviyo was also named a Strong Performer in the Forrester Wave for Email Marketing in Q1 2026, the first time it has been formally evaluated in that report. The positioning is a useful data point, though “Strong Performer” rather than “Leader” suggests Klaviyo’s enterprise and B2B capabilities still lag behind platforms like Salesforce Marketing Cloud and HubSpot in Forrester’s methodology. For ecommerce specifically, the platform competes well above its Forrester ranking would imply.

Bottom Line

Composer is the headline and it is legitimately interesting — not because the concept of AI-generated campaigns is new, but because Klaviyo has the ecommerce performance data to make AI-generated campaigns meaningfully better than what a generic LLM would produce. The private beta limitation means most users cannot evaluate it yet, but it is worth watching.

RCS, Customer Agent improvements, and multi-email profiles are solid operational updates. None of them are reasons to switch to Klaviyo if you are not already on it, but they are genuine improvements for existing customers.

The persistent knock on Klaviyo remains pricing. For brands scaling from 10,000 to 100,000 contacts, the cost curve is steep, and the Spring 2026 features are mostly additive to an already capable platform rather than addressing the cost-value gap.

For brands that are already committed to the platform, this is one of the better quarterly updates in recent memory. For brands still evaluating whether Klaviyo is right for them, the fundamentals — cost, ecommerce depth, segmentation power — remain the real decision criteria. The AI features are a bonus, not a reason.

Sources

1. Klaviyo — Composer Launch Announcement — accessed 2026-04-25
2. Klaviyo — What's New Spring 2026 — accessed 2026-04-25
3. Klaviyo — Q1 2026 Product Updates Community Post — accessed 2026-04-25
4. Klaviyo — Forrester Wave Email Marketing Q1 2026 — accessed 2026-04-25