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Data-driven messaging automation

Customer.io

Event-driven messaging platform for product teams, sending email, push, in-app and SMS from behavioural data, billed by profiles with a million emails included on the entry plan.

Visit customer.io ↗ Alternatives Trial
Customer.io homepage
§1

Overview

Customer.io is a messaging automation platform for product-led companies. Your app sends it people, objects (such as accounts) and events; you then build campaigns and journeys that react to that data, sending email, push notifications, in-app messages, SMS or webhooks.

Billing is by profiles, which include both people and objects, measured at the highest count reached in each billing period, including profiles you deleted during it. Essentials includes 5,000 profiles and a million emails a month, with published overage rates of $0.009 per profile and $0.12 per 1,000 emails.

Premium and Enterprise use custom volume pricing and add more object types, premium integrations, onboarding help and HIPAA compliance. Premium and Enterprise plans are typically billed on longer terms; overages are charged monthly.

Customer.io expects engineering time to send clean event data. It is more than most side projects need but fits teams that want lifecycle messaging driven by product behaviour.

§2

Pricing and plans

Plan Price What you get
Essentials $100/mo 5,000 profiles (people + objects), 1 million emails/mo, 2 object types, basic data integrations; overage $0.009/profile
Premium Custom Custom profile and email volume, 10 object types, premium support, 90-day onboarding, HIPAA; overage $0.004/profile
Enterprise Custom Dedicated infrastructure and support, best volume pricing

The pricing page could not be read in full; its visible text confirms 5,000 profiles, 1 million emails a month and the overage rates, and the $100 Essentials price is taken from several current third-party listings (hellostack.io, softwareadvice.com) that agree. costAt at 10,000 and 50,000 is calculated as $100 plus $0.009 per extra profile. Profiles are billed on a high-water mark that includes profiles deleted during the period, and people and objects both count. Push, in-app and webhook messages are unlimited under a fair-use policy of 60 times your plan's profiles. New Essentials accounts start with a daily email sending limit that rises with sending history. HIPAA compliance is listed for Premium.

Source: customer.io/pricing · prices as published, excluding tax.

§3

What it does

Event-triggered journeys
Visual workflow builder driven by events and attributes from your product.
Multichannel
Email, push, in-app, SMS and webhooks; push, in-app and webhooks are unlimited under fair use.
Objects
Model accounts or other entities as objects (2 types on Essentials, 10 on Premium).
Data pipelines
Collect and route customer data to and from other tools.
AI agent, CLI and MCP
An AI agent in the product plus a CLI and MCP server for external agents.
§4

Strengths and limitations

Strengths

  • Rich event and object data model for B2B and B2C products
  • One million emails included on the entry plan
  • Published overage rates
  • Unlimited push, in-app and webhook messages under fair use

Limitations

  • No free plan; entry price around $100 a month
  • Deleted profiles still count in the billing period they existed
  • Profiles in test or dev workspaces count toward billing
  • New accounts start with a daily sending limit
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Who it suits

Good for

  • SaaS and mobile apps with instrumented product events
  • Teams running cross-channel onboarding and retention
  • Healthcare products needing HIPAA (Premium)

Look elsewhere if

  • Simple newsletters or hobby projects
  • Teams without engineering time to send event data
§6

Alternatives to Customer.io

Tool From Free option Stages
Klaviyo Ecommerce marketing platform
$20/mo Free tier
Twilio SendGrid Email API Email API and SMTP relay
$19.95/mo Trial
GetResponse Email marketing and automation
$19/mo Free tier
ActiveCampaign Marketing automation platform
$15/mo Trial
Brevo Email marketing and transactional platform
$9/mo Free tier
Mautic Open-source marketing automation
— Free tier

All email marketing and newsletters →

§7

Questions

How does Customer.io billing work?

By profiles (people plus objects) on a high-water mark, with a set number of emails per plan and overages at $0.009 per profile and $0.12 per 1,000 emails on Essentials.

Does Customer.io have a free plan?

No. It offers a trial; Essentials is the entry plan.

Do test workspaces count toward Customer.io profiles?

Yes. Profiles in all workspaces, including ones named test or sandbox, count toward billing.

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