If you're outgrowing Klaviyo because you need more control, better API flexibility, or infrastructure built for product-led growth, you're not alone. For teams that need transactional messaging, cross-channel orchestration, and programmable workflows, Klaviyo's marketing-first approach often falls short. If your primary use case is ecommerce email campaigns and SMS marketing for a Shopify store, Klaviyo remains a solid choice for traditional marketing teams.
This post covers the best Klaviyo alternatives, what each does well, and how they compare on pricing, flexibility, and cross-team collaboration.
The best Klaviyo alternatives at a glance
- Knock. Best for cross-functional teams that need dependable customer engagement infrastructure with visual tooling for non-technical stakeholders.
- Customer.io. Best for product-led SaaS companies that want behavior-driven messaging with a visual workflow builder.
- Braze. Best for enterprise mobile-first brands that need real-time cross-channel engagement at scale.
- Iterable. Best for enterprise marketing teams that need AI-powered lifecycle campaign orchestration.
- OneSignal. Best for teams that need affordable push notifications and basic cross-channel messaging.
- Novu. Best for engineering teams that want open-source notification infrastructure they can self-host.
- Courier. Best for developers who need a unified API to orchestrate notifications across multiple providers.
Why people look for alternatives to Klaviyo
Klaviyo is a B2C marketing platform designed primarily for ecommerce brands. It does email and SMS campaigns well, with a strong Shopify integration, behavioral segmentation, and predictive analytics for purchase-driven workflows.
That said, there are several reasons teams look elsewhere:
- Limited developer control. Klaviyo's API is designed around marketing workflows, not programmable notification logic. Teams that need transactional messaging, custom routing rules, or event-driven workflows often hit walls when trying to extend Klaviyo beyond campaign sends.
- No real cross-channel notification orchestration. While Klaviyo supports email and SMS (and has added push), it lacks the multi-channel orchestration needed for in-app messaging, chat integrations (Slack, Teams), and intelligent channel routing. Teams building product-led experiences need infrastructure that goes beyond marketing channels.
- Pricing scales with contacts, not usage. Klaviyo's pricing is tied to active profiles, which means you pay for contacts whether you message them or not. For high-volume transactional use cases or companies with large user bases, this model can become expensive and unpredictable.
- Not built for cross-functional collaboration. Klaviyo is a marketing tool. Engineering, product, and operations teams have limited visibility into notification logic, templates, and delivery. Organizations where multiple teams need to collaborate on messaging often outgrow Klaviyo's single-team model.
Why Knock is a strong Klaviyo alternative
Knock is a customer engagement infrastructure platform that provides a complete system for powering messaging across in-app, email, SMS, push, and chat apps. Unlike marketing automation tools, Knock is designed as a layer between your application logic and delivery providers, giving engineering teams full API control while providing visual tooling that product, growth, and operations teams can use without writing code.
Best for
Organizations where engineering, product, growth, and operations teams all need to collaborate on customer messaging. Knock is a strong fit for B2B SaaS companies, marketplaces, and product-led businesses that need transactional messaging, cross-channel orchestration, and programmable workflows, all with the power and control that comes from API-first infrastructure.
Strengths
- API-first infrastructure with visual tooling. Knock provides comprehensive APIs and SDKs for every major language, while its workflow builder, template editor, and dashboard give non-technical team members the ability to manage notification logic, content, and preferences without code deploys.
- True cross-channel orchestration. Knock supports in-app messaging (feeds, modals, banners), email, SMS, push, and chat apps (Slack, Teams, Discord) from a single workflow. Intelligent routing, batching, throttling, and conditional logic are built in, so you can design notification experiences that respect user attention across every channel.
- Enterprise-grade infrastructure for every team size. Knock handles multi-tenancy, version control, environment management, preference APIs, and observability out of the box. Companies like Vercel, Amplitude, and Webflow use Knock to power their notification systems.
- Pre-built components that ship fast. Knock's React SDK includes pre-built notification feeds, inboxes, and toasts, plus headless components for complete design control. Teams regularly ship in-app notification experiences in days instead of months.
Limitations
- Learning curve for less technical teams. Knock is developer-first, which means initial setup and integration require engineering involvement. Once configured, non-technical team members can manage workflows and templates through the dashboard.
Pricing
Knock offers a free Developer plan (10K messages/month), a Starter plan at $250/month (50K messages included, then $0.005 per additional message), and custom Enterprise pricing with volume-based discounts. Knock only charges for messages sent, not for workflow triggers, and failed or bounced messages are not billed.
How it compares to Klaviyo
Klaviyo is a marketing platform built for ecommerce email and SMS campaigns. Knock is customer engagement infrastructure built for product and transactional messaging across every channel. Where Klaviyo charges based on active profiles, Knock charges based on messages sent, which gives teams more predictable costs at scale. Knock's biggest advantage is that it serves engineering, product, growth, and operations teams from a single platform, rather than being a tool only marketers use.
Other Klaviyo alternatives
Customer.io
Customer.io is a marketing automation platform designed for product-led SaaS companies that need behavior-driven messaging across email, SMS, push, and in-app channels.
Best for
Technical marketing and growth teams at SaaS companies that want to trigger messages based on user events and behavioral data, with more flexibility than traditional marketing platforms.
Strengths
- Event-driven messaging. Customer.io's workflow builder triggers messages based on real-time user behavior, making it a strong fit for product-led growth use cases like onboarding, activation, and re-engagement.
- Visual campaign builder with API flexibility. The platform balances a marketer-friendly interface with enough API access that technical teams can extend and customize their messaging logic.
- Broad channel support. Customer.io supports email, SMS, push, and in-app messaging, covering the core channels most SaaS products need.
Limitations
- Technical setup required. Getting full value from Customer.io requires engineering effort to implement event tracking and data integrations. Less technical teams may find the initial setup steep.
- Not true notification infrastructure. While Customer.io handles marketing and some transactional messaging well, it lacks the workflow primitives (batching, throttling, channel failover) and developer tooling that engineering teams need for complex notification systems.
- Pricing rises with scale. The Essentials plan starts at $100/month for 5,000 profiles, and costs grow as your contact list expands.
Pricing
Customer.io's Essentials plan starts at $100/month for 5,000 profiles with up to 1 million email sends. Premium and Enterprise tiers are available for larger teams with custom pricing.
How it compares to Klaviyo
Customer.io is a better fit for SaaS companies than Klaviyo, which is primarily built for ecommerce. Customer.io's event-driven architecture gives growth teams more flexibility to trigger messages based on product behavior rather than purchase history. However, Customer.io is still a marketing tool at its core, while Knock provides the infrastructure layer that engineering teams need for complex notification systems.
Braze
Braze is an enterprise customer engagement platform focused on mobile-first, real-time cross-channel messaging at scale.
Best for
Large, well-funded companies with dedicated marketing operations teams that need enterprise-grade mobile engagement across push, in-app, email, SMS, and web channels.
Strengths
- Mobile-first architecture. Braze is built around mobile engagement, with strong push notification and in-app messaging capabilities that have been battle-tested at massive scale.
- Real-time data processing. Braze processes behavioral data in real time, enabling personalized messaging triggered by user actions as they happen.
- Enterprise-scale reliability. Braze's infrastructure handles high-volume messaging with proven reliability, making it a fit for companies with millions of active users.
Limitations
- Significant cost. Braze's pricing is enterprise-only and contract-based, typically ranging from $60,000 to $200,000+ per year. This puts it out of reach for most startups and mid-market companies.
- Complex implementation. Braze is rated as moderately complex to implement and requires dedicated technical resources to configure, maintain, and optimize.
- Marketing-team focused. Braze is designed for marketing operations teams. Engineering and product teams have limited direct involvement in day-to-day notification management.
Pricing
Custom enterprise pricing based on contract size, channels, and message volume. No self-serve plans or free tiers are available.
How it compares to Klaviyo
Braze is a step up from Klaviyo for enterprise brands that need mobile-first engagement and real-time personalization across channels. However, both platforms are marketing-team tools. Neither provides the developer infrastructure, workflow primitives, or cross-team collaboration model that platforms like Knock offer for product and transactional messaging.
Iterable
Iterable is an enterprise cross-channel marketing platform that combines AI-powered automation with flexible workflow orchestration for lifecycle campaigns.
Best for
Enterprise marketing teams that need sophisticated lifecycle campaign automation across email, SMS, push, in-app, and web, with AI-powered optimization built in.
Strengths
- Flexible workflow orchestration. Iterable's Studio workflow builder gives marketing teams granular control over multi-step, multi-channel campaigns with branching logic and experimentation.
- AI-powered optimization. Iterable's AI features help optimize send times, channel selection, and content personalization without manual configuration.
- Strong data integration. Iterable supports flexible data models and integrates with major data warehouses and CDPs, making it easier to unify customer data for campaign targeting.
Limitations
- Enterprise pricing and complexity. Iterable uses custom, enterprise pricing and requires dedicated resources for implementation and ongoing management.
- Marketing-team oriented. Like Braze, Iterable is designed for marketing teams. Engineering involvement is often required for setup and data integration, but the day-to-day tool is built for marketers.
- Limited transactional messaging. While Iterable can handle some transactional use cases, it lacks the developer-first primitives (batching, throttling, preference APIs, version control) that engineering teams need for complex notification logic.
Pricing
Custom enterprise pricing based on audience size, messaging volume, and feature access. No self-serve options are available.
How it compares to Klaviyo
Iterable is better suited for non-ecommerce companies that need advanced lifecycle automation and AI-powered optimization. Where Klaviyo is tightly coupled to Shopify and ecommerce workflows, Iterable is more flexible in its data model and use cases. However, both are marketing-first platforms that require engineering teams to look elsewhere for transactional messaging infrastructure.
OneSignal
OneSignal is a messaging platform that started as a push notification service and has expanded to support email, SMS, and in-app messaging.
Best for
Teams that need an affordable, easy-to-implement push notification solution with basic cross-channel messaging capabilities.
Strengths
- Generous free tier. OneSignal offers a free plan that supports a meaningful volume of push notifications, making it accessible for startups and small teams.
- Fast push notification setup. OneSignal's SDK is straightforward to implement for mobile and web push, with solid documentation and broad platform support.
- Growing channel support. OneSignal has expanded beyond push to include email, SMS, and in-app messaging, giving teams a single platform for basic cross-channel messaging.
Limitations
- Limited workflow sophistication. OneSignal's automation and orchestration capabilities are basic compared to dedicated messaging infrastructure or enterprise engagement platforms.
- Less suited for complex transactional use cases. OneSignal works well for broadcast and simple triggered messaging, but lacks the workflow primitives (conditional routing, batching, throttling) needed for complex transactional notification systems.
- Push-first architecture. While OneSignal has added channels, its core strength remains push notifications. Teams with advanced email or in-app messaging needs may outgrow the platform.
Pricing
OneSignal offers a free tier, a Growth plan starting at $9/month, a Professional plan at $99/month, and custom Enterprise pricing.
How it compares to Klaviyo
OneSignal and Klaviyo serve different primary use cases. Klaviyo is built for ecommerce email and SMS marketing. OneSignal is built around push notifications with expanding channel support. OneSignal is a better fit for mobile-first products that need affordable push infrastructure, while Klaviyo is stronger for email-driven marketing campaigns. Neither provides the cross-team, API-first infrastructure that platforms like Knock offer.
Novu
Novu is an open-source notification infrastructure platform that provides a unified API for managing notifications across in-app, email, SMS, push, and chat channels.
Best for
Engineering teams that want open-source notification infrastructure they can self-host and customize, with full control over their notification stack.
Strengths
- Open-source flexibility. Novu's open-source model gives engineering teams full visibility into the codebase and the ability to self-host and customize the platform to their needs.
- Unified notification API. Novu provides a single API for sending notifications across multiple channels, simplifying the integration layer for engineering teams.
- Active developer community. Novu has a growing open-source community that contributes to the platform and provides peer support.
Limitations
- Self-hosting overhead. Teams that choose to self-host Novu take on the operational burden of maintaining, scaling, and monitoring the infrastructure themselves.
- Less mature platform. Novu is earlier in its development compared to more established platforms, which means fewer enterprise features, integrations, and production-hardened capabilities.
- Limited non-technical tooling. Novu is designed for developers. Product, marketing, and operations teams have fewer self-serve tools for managing notification content and workflows compared to platforms like Knock.
Pricing
Novu offers a free open-source self-hosted option, a free cloud tier, and paid cloud plans for teams that want managed infrastructure. Enterprise pricing is available for larger organizations.
How it compares to Klaviyo
Novu and Klaviyo are fundamentally different tools. Klaviyo is a marketing platform for ecommerce campaigns. Novu is developer-focused notification infrastructure. Novu is a fit for engineering teams that want full control over their notification stack, while Klaviyo serves marketing teams running email and SMS campaigns.
Courier
Courier is a notification infrastructure platform that provides a unified API for orchestrating messages across email, SMS, push, in-app, and chat channels.
Best for
Developers who need a single API to manage notification delivery across multiple providers, with a visual designer for notification templates.
Strengths
- Provider abstraction. Courier sits between your application and your delivery providers (SendGrid, Twilio, etc.), letting you switch providers without code changes.
- Visual template designer. Courier's template builder enables non-technical team members to design notification content across channels without developer involvement.
- Multi-channel routing. Courier supports intelligent routing across channels with configurable fallback logic.
Limitations
- Smaller ecosystem. Courier has a smaller customer base and community compared to more established platforms, which can mean fewer integrations and less community support.
- Less comprehensive workflow engine. Courier's orchestration capabilities are more focused on delivery routing than complex workflow logic with batching, delays, and conditional branching.
- Limited pre-built UI components. Courier doesn't provide the same depth of pre-built in-app notification components (feeds, inboxes, toasts) that platforms like Knock offer.
Pricing
Courier offers a free tier, with paid plans scaling based on notification volume. Enterprise pricing is available for larger organizations.
How it compares to Klaviyo
Courier is notification delivery infrastructure, while Klaviyo is a marketing automation platform. Courier is built for developers who need to send transactional and product notifications across channels, while Klaviyo is built for marketers running ecommerce campaigns. The two tools serve different problems entirely.
How to choose the right Klaviyo alternative
The right choice depends on your team structure, use cases, and growth stage. Here are recommendations by scenario.
Small teams. Knock provides the fastest path to production for small teams that need cross-channel messaging without building infrastructure from scratch. OneSignal is a solid option if push notifications are your primary channel and budget is tight.
Enterprise. For enterprise organizations where multiple teams (engineering, product, growth, and operations) need to collaborate on messaging, Knock provides the technical control developers require with visual, low-code tooling to empower non-technical stakeholders. Braze and Iterable are strong options for enterprises where marketing operations teams own the messaging stack.
Technical teams. Knock and Novu provide API-first infrastructure designed for engineering workflows. Knock offers a managed service with enterprise-grade reliability, while Novu gives teams the option to self-host for full control.
Non-technical teams. Iterable and Customer.io balance marketing capabilities with ease of use, offering visual workflow builders and campaign tools that growth and marketing teams can operate with limited engineering support.
Budget-constrained. Knock and OneSignal offer predictable pricing that scales reasonably with growth. Knock's message-based billing is transparent and avoids the contact-based pricing surprises that come with platforms like Klaviyo.
Compliance-heavy. Knock and Braze provide enterprise-grade security, SOC 2 compliance, and data residency options. Knock also offers HIPAA compliance with BAAs on its Enterprise plan.
Klaviyo alternatives FAQs
Do these alternatives support the same channels as Klaviyo?
Most alternatives in this post support more channels than Klaviyo. While Klaviyo focuses on email and SMS (with limited push), platforms like Knock, Braze, and Iterable support in-app messaging, push, chat apps (Slack, Teams, Discord), and webhooks in addition to email and SMS. The channel gap is one of the primary reasons teams look for Klaviyo alternatives.
Which alternatives work well for cross-functional teams?
Knock is purpose-built for cross-functional collaboration. Its API-first infrastructure serves engineering teams while its visual workflow builder, template editor, and dashboard give product, growth, and operations teams the ability to manage messaging without code. Braze and Iterable also support marketing-engineering collaboration, though they center the experience on marketing teams.
Which alternatives offer the most control over messaging logic?
Knock and Novu offer the most control for engineering teams, with programmable workflows, conditional logic, batching, throttling, and preference management available through APIs and SDKs. Customer.io provides event-driven automation that gives growth teams meaningful control. Braze and Iterable provide visual campaign builders with automation features, but their logic is oriented toward marketing use cases rather than transactional messaging infrastructure.
How do these alternatives compare for transactional notifications?
Knock, Novu, and Courier are purpose-built for transactional and product notifications with the reliability, delivery guarantees, and workflow primitives that transactional use cases demand. Customer.io handles some transactional messaging alongside marketing campaigns. Braze and Iterable can support transactional messages but are primarily designed for marketing engagement. Klaviyo is the least suited for transactional use cases among the platforms in this post.
Engage customers with Knock
Knock is customer engagement infrastructure that gives your team the power and control to deliver the right message, on the right channel, at the right time. Ship in-app messaging in days, orchestrate cross-channel workflows without building infrastructure, and give every team the tools they need to collaborate on messaging.
Get started for free or talk to our team to see how Knock can replace your current notification stack.