Campaign Monitor vs Customer.io
Campaign Monitor and Customer.io are both popular choices in the email marketing platform space. Campaign Monitor has been around since 2004, giving it a 8-year head start over Customer.io (founded 2012). Campaign Monitor is the more affordable option at $12/mo, which is $88 less than Customer.io's $100/mo entry point. Campaign Monitor has the edge with ecommerce integrations.
Quick Verdict
Campaign Monitor wins on price, deliverability, integrations.
Customer.io wins on rating.
Best for most users: Campaign Monitor (agencies).
Campaign Monitor
Beautifully crafted email marketing
Campaign Monitor is particularly well-suited for agencies and brands that need polished, branded email campaigns. Its client management features and beautiful template builder make it a popular choice for marketing agencies managing multiple client accounts.
Customer.io
Behavioral messaging platform for product-led SaaS and tech companies
Customer.io is a behavioral messaging platform built for product-led SaaS companies that need to trigger automated emails, SMS, push notifications, and in-app messages based on real-time user events. Its visual workflow builder and Liquid templating provide deep personalization, while the built-in Data Pipelines act as a lightweight CDP. Trusted by 8,000+ companies including Notion and Segment, it starts at $100/month for 5,000 profiles.
Feature Comparison
| Feature | Campaign Monitor | Customer.io |
|---|---|---|
| Rating | 4.1/5 | 4.4/5 |
| Starting Price | $12/mo | $100/mo |
| Free Plan | No free plan | No free plan |
| Founded | 2004 | 2012 |
| Email Templates | 120 | 30 |
| Integrations | 250 | 150 |
| Deliverability Rate | 97.5% | 96% |
| Marketing Automation | Yes | Yes |
| A/B Testing | Yes | Yes |
| Landing Pages | No | No |
| Segmentation | Yes | Yes |
| Drag & Drop Editor | Yes | Yes |
| SMS Marketing | Yes | Yes |
| Ecommerce Features | Yes | No |
| API Access | Yes | Yes |
| Multi-Language | Yes | Yes |
| Web Push Notifications | No | Yes |
| Live Chat | No | No |
| Advanced Analytics | Yes | Yes |
Campaign Monitor: Pros & Cons
Pros
- + Excellent email template builder
- + Strong agency features and client management
- + Good deliverability
- + Time zone sending optimization
- + Link review feature prevents broken links
Cons
- − No free plan
- − Lite plan caps at 2,500 emails
- − Premier plan expensive ($159/mo)
- − No landing page builder
- − Limited automation on lower tiers
Customer.io: Pros & Cons
Pros
- + Powerful visual workflow builder with real-time event-based triggers for behavioral automation
- + Omnichannel messaging across email, SMS, push notifications, in-app, and webhooks in one platform
- + Built-in Data Pipelines that serve as a lightweight CDP, unifying web, mobile, and backend data
- + Segment builder is intuitive enough for marketers without requiring dedicated engineering support
- + Startup Program offers up to 12 months free for qualifying early-stage companies
Cons
- − Essentials plan starts at $100/month for only 5,000 profiles — expensive for small teams
- − Steep learning curve for non-technical users, especially with Liquid templating syntax
- − Pricing scales aggressively past 10K profiles with significant jumps between plan tiers
- − Template editor feels restrictive for highly custom-coded email layouts
- − Searching for past messages and editing templates can be unintuitive and slow
The Verdict
Customer.io edges ahead with a 4.4/5 rating compared to Campaign Monitor's 4.1/5. The gap comes mainly from support (4.3 vs 3.8) and ease of use (4.7 vs 4.3). On deliverability, Campaign Monitor reports 97.5% compared to 96% for Customer.io — a meaningful difference if inbox placement is critical for your campaigns.
| Criterion | Weight | Campaign Monitor | Customer.io |
|---|---|---|---|
| Starting Price | 30% | $12/mo Winner | $100/mo |
| Deliverability | 25% | 97.5% Winner | 96% |
| Rating | 25% | 4.1/5 | 4.4/5 Winner |
| Integrations | 10% | 250 Winner | 150 |
| Free Tier | 10% | No | No |
Weights determine how much each criterion counts toward the final score. See full methodology
Choose Campaign Monitor if…
- + You want lower starting costs ($12/mo)
- + You need ecommerce integrations
- + You're a agencies
- + You're a brands
Choose Customer.io if…
- + You're a product led saas companies with event driven messaging needs
- + You're a technical marketing teams that want advanced automation with liquid logic
- + Powerful visual workflow builder with real-time event-based triggers for behavioral automation