Customer.io crossed $100M: A note from the CEO 

You sent 64 billion messages in the past 12 months through Customer.io across push notifications, email, in-app messages, SMS, and webhooks. Messages that converted browsers into buyers, turned trial users into advocates, and rescued at-risk users into loyal fans. In September, your success became ours: Customer.io crossed $100M in annual recurring revenue (ARR).

When my co-founder John Allison and I started Customer.io in 2012, we wanted to power communication that people actually wanted to receive. We talked with marketers who had ambitious ideas about the experience they wanted for their customers. Back then, they were limited by inflexible tools, disconnected data, and dependence on the engineering process. We set out to change that.

Today, 8,000+ companies trust Customer.io to transform how they communicate with their customers. We appreciate the trust and validation that we’re building something that delivers for you.

• 2012: Our first 5 customers joined based on our vision of a product that would “send emails based on what users did or didn’t do in your app.”
• 2014: Your volume had us trying to scale! Our team went fully distributed this year.
• 2016: 1,000 of you were with us in the year we expanded beyond email to push, SMS, Slack, and webhooks.
• 2018: We introduced a Premium Plan and HIPAA compliance in response to you becoming more sophisticated.
• 2020: Your campaign experience changed with the Visual Workflow Builder, the canvas for creating branching customer journeys.
• 2021: You had the opportunity to invest at ~$20m ARR in a crowdfunding round and around 2,500 people invested, including many of you as customers.
• 2022: Your needs evolved for mobile so we introduced new SDKs, in-app notifications, and an updated editor experience via our Gist and Parcel acquisitions.
• 2023: Customer data platform capabilities multiplied the number of places you could get data in and out.
• 2024: You saw stability improvements, performance upgrades, and refinements across the platform based on your feedback at scale.
• 2025 to date: You're seeing us bring AI capabilities to every part of Customer.io.

Each milestone and product change represents thousands of conversations with customers, feature requests that shaped our roadmap, and honest feedback about what wasn't working. Our partnership with you has always been our foundation and continues into the future.

Crossing $100M ARR isn't just a number; it's a capability unlock. It means we can now:

• Do more in parallel to move at the pace the market demands.
• Attract partnerships that require scale. For example, maintaining a robust ecosystem of agency partners to help you do more, and integration partners to connect into all of the places your data is useful.
• Make bigger bets on the future, either through new innovation on top of the terabytes of data you store with us and our battle-tested infrastructure, or through acquisitions that enhance the value you get from Customer.io.

But here's what it doesn't change: We won't become the platform that's too big to listen. We won't sacrifice reliability for flashy features. And your feedback will still shape what we build.

We’ve sharpened our perspective on what AI will do for customer engagement, but I won’t pretend we can perfectly predict where the market is going. AI is transforming teams and workflows faster than any of us expected. AI-native upstarts launch every month. Incumbent platforms are racing to add AI features. Privacy regulations keep evolving. The market is moving, and the pressure to keep up is real.

We believe that the winners won’t be those with the flashiest demos. The hype is exciting, but it doesn’t deliver lasting value. The winners will be the platforms nimble enough to evolve to changing customer needs over time and honest enough to rebuild what isn’t working.

Here’s an indication of where we’re going through some AI features that are live today:

1. Your business profile for AI personalization: We’re already using what we know about your business to personalize the experience you get in our product. From our recommended segments to how our Assistant answers, it’s all informed by what we understand about your business.
2. An Assistant that does work for you: Our AI assistant is more than a chatbot with access to our documentation. Every week, the team working on it gives it more capabilities with the ultimate goal of safely and predictably performing any task in Customer.io that a human can do.
3. Unlocking advanced workflows like translation: In the past, translation required synchronizing content with third-party tools and managing teams of translators. Now with AI translation, you can convert your content into over 200 languages at the click of a button.

We’ve heard from many customers who want even more; LLMs integrated into personalization or as part of experimentation. A few of you have even shared that you want to press a button and let us figure out how to drive more business outcomes! I love the ambition. As we build out new capabilities, I’m confident our approach will give you the power you’re looking for.

As we enter this next phase, your voice matters more than ever. Tell us:

What's working for you? When an AI feature saves you time or a campaign drives measurable results, reach out to your Customer Success Manager or our support team to let us know. Your success stories guide where we decide to double down.

What could we improve? If something isn't delivering value or our AI suggestions miss the mark, that's signal we need. We move fast, but we can't fix what we don't see.

What do you wish was possible? The gap between what Customer.io does today and what would make your job dramatically easier is what we want on our roadmap.

This isn't a suggestion box that disappears into a void. This is how we've always built, and it's how we'll build the future.

To every customer who has trusted us with your customer relationships: thank you. You've been patient through our growing pains in the early years. You've stayed with us when competitors made big promises (or you've come back when they didn't deliver). You've pushed us to be better with every feature request.

Here's my commitment as we scale: We won't add AI just to check boxes. We won't sacrifice the reliability you depend on for innovation theater. We won't forget that your business success—measured in your conversions, your retention, and your revenue—is the only thing that matters.

Reaching $100M ARR isn't the finish line, it's the start. It means we now have the resources to build the platform we've always envisioned for you. One where sophisticated customer engagement is accessible to companies of every size, where we handle complexity so you can focus on strategy, and where success is measured in business outcomes, not messages sent.

Here's to the next chapter of sending messages your customers actually want to receive.