How do Customer.io and SparkPost prices compare?

Customer.io: $100/month on Essentials at 25,000 profiles. SparkPost: $80/month on Growth at 100,000 emails. Different billing units are not an equal-workload comparison. Estimates exclude unlisted add-ons and taxes.

What matters for transactional email?

Review SMTP or API integration, domain authentication, bounce and complaint events, suppression handling and delivery-log retention.

Can I compare marketing and agent email by sends?

Only when the published plan actually bills by sends. Contacts, subscribers and inboxes stay in their own billing units.

What features and free access does Customer.io list?

Behavioral messaging, Lifecycle workflows, Event triggers. Free access: Trial. Check plan-specific availability and current terms on the provider's official pricing page.

What features and free access does SparkPost list?

Deliverability analytics, Enterprise scale, Predictive signals. Free access: Trial availability varies. Check plan-specific availability and current terms on the provider's official pricing page.

Email APIs · side by side

Customer.io vs SparkPost

Compare Customer.io, SparkPost by sending volume, delivery webhooks, inbound email, domain limits and retention.

Email APIs pricing calculator

These providers bill in different units. Each estimate uses its own workload; there is no same-volume price winner.

Customer.io

Number of profiles

25K

SparkPost

Monthly emails

100K

Customer.io

$100 / mo

Essentials · 25K profiles

SparkPost

$80 / mo

Growth · 100K emails

Listed USD plan fees and tracked usage only. Unlisted compute, transfer, extras, taxes and contract terms are excluded. Custom or unsupported plan usage is not estimated.

Email APIs overview & pricing

Email APIs	Customer.io	SparkPost
Provider	Customer.io	Bird
Billing unit	profiles	emails
Plan at selected usage	Essentials	Growth
Monthly estimate	$100/mo	$80/mo
Workload	25K profiles	100K emails
Free access	Trial	Trial availability varies
Published plans	Essentials, Premium, Enterprise	Free, Startup, Growth, Enterprise
Prices checked	2026-10-08	2026-10-08

Provider

Customer.io: Customer.io
SparkPost: Bird

Billing unit

Customer.io: profiles
SparkPost: emails

Plan at selected usage

Customer.io: Essentials
SparkPost: Growth

Monthly estimate

Customer.io: $100/mo
SparkPost: $80/mo

Workload

Customer.io: 25K profiles
SparkPost: 100K emails

Free access

Customer.io: Trial
SparkPost: Trial availability varies

Published plans

Customer.io: Essentials, Premium, Enterprise
SparkPost: Free, Startup, Growth, Enterprise

Prices checked

Customer.io: 2026-10-08
SparkPost: 2026-10-08

Email APIs monthly cost

Customer.io: $100SparkPost: $80

Different workloads, separate estimates

Separate transactional delivery from campaigns, outreach and agent inboxes. Compare monthly sends and daily caps; contacts, seats and inboxes are not sending allowances. Budget separately for dedicated IPs, validation and attachments.

Email APIs feature comparison

Email APIs	Customer.io	SparkPost
Sending domains	Not listed	1,000
AI Agent (beta): Session limits	Standard	Not listed
AI Agent (beta): Persistent Memory		Not listed
AI Agent (beta): Core Execution Skills		Not listed
AI Agent (beta): Custom Execution Skills	3	Not listed
AI Agent (beta): Routines: # of tasks	1	Not listed
AI Agent (beta): Routines: frequency	Weekly	Not listed
Monthly email sends	1M	Not listed
Transactional emails		Not listed
Monthly push and in-app	Unlimited	Not listed
Mobile SDKs		Not listed
Monthly SMS sends	Custom	Not listed
WhatsApp (Native)		Not listed
LINE		Not listed
Webhook (send & receive)	Unlimited	Not listed
Anonymous messages	— Not included	Not listed
LLM actions		Not listed
Visual workflow builder		Not listed
Cross-channel campaign automation		Not listed
Send-time optimization		Not listed
In-app message suggestions		Not listed
API-triggered broadcasts		Not listed
Scalable Personalization		Not listed
Custom SMTP		Not listed
Profiles (people + objects)	5,000	Not listed
People attributes	Unlimited	Not listed
Custom objects		Not listed
Object types	2	Not listed
Segments		Not listed
AI-powered segment builder		Not listed
Suggested segments		Not listed
Nested data		Not listed
Ad audience sync		Not listed
Custom collections	— Not included	Not listed
Drag-and-drop visual editor		Not listed
Code editor		Not listed
AI-generated global styles		Not listed
AI translator for messages		Not listed
Email content analysis		Not listed
Reusable components		Not listed
Saved templates & version control		Not listed
Inbox previews	25	Not listed
Monthly API calls	Unlimited	Not listed
Integrations	Basic	Not listed
MCP server		Not listed
Data index		Not listed
Connected forms		Not listed
Privacy management		Not listed
Reverse ETL		Not listed
Data warehouse destinations	— Not included	Not listed
Data replay	— Not included	Not listed
Dashboards		Not listed
Campaign reporting		Not listed
Workspace performance dashboard		Not listed
Survey analysis		Not listed
Data export		Not listed
A/B & multivariate testing		Not listed
Conversion tracking		Not listed
Universal search		Not listed
SSO & 2-factor authentication		Not listed
US / EU data centers		Not listed
SOC Tier II Compliance		Not listed
Standard role-based permissions		Not listed
Custom role-based permissions	— Not included	Not listed
Managed deliverability	— Not included	Not listed
HIPAA Compliance	— Not included	Not listed
Audit logging & data governance	— Not included	Not listed
Dedicated hardware	— Not included	Not listed
Documentation		Not listed
Community support		Not listed
Email support		Not listed
Chat support	— Not included	Not listed
Onboarding support	— Not included	Not listed
Dedicated Customer Success Manager	— Not included	Not listed
Migration support	— Not included	Not listed
Dedicated Technical Implementation Specialist	— Not included	Not listed
Shared Slack channel	— Not included	Not listed
2-hour first outreach response time	— Not included	Not listed
User seats	Unlimited	Not listed
Workspaces	2	Not listed
Additional people & object profiles	$0.009	Not listed
Emails / month	Not listed	100K to 2.5M
Webhook endpoints	Not listed	10
Sending IP	Not listed	Dedicated IPs (add-on)

Sending domains

Customer.io: Not listed
SparkPost: 1,000

AI Agent (beta): Session limits

Customer.io: Standard
SparkPost: Not listed

AI Agent (beta): Persistent Memory

Customer.io
SparkPost: Not listed

AI Agent (beta): Core Execution Skills

Customer.io
SparkPost: Not listed

AI Agent (beta): Custom Execution Skills

Customer.io: 3
SparkPost: Not listed

AI Agent (beta): Routines: # of tasks

Customer.io: 1
SparkPost: Not listed

AI Agent (beta): Routines: frequency

Customer.io: Weekly
SparkPost: Not listed

Monthly email sends

Customer.io: 1M
SparkPost: Not listed

Transactional emails

Customer.io
SparkPost: Not listed

Monthly push and in-app

Customer.io: Unlimited
SparkPost: Not listed

Mobile SDKs

Customer.io
SparkPost: Not listed

Monthly SMS sends

Customer.io: Custom
SparkPost: Not listed

WhatsApp (Native)

Customer.io
SparkPost: Not listed

LINE

Customer.io
SparkPost: Not listed

Webhook (send & receive)

Customer.io: Unlimited
SparkPost: Not listed

Showing 15 of 84

Which email providers fit your needs?

Customer.io features & plan notes

Behavioral messaging
Lifecycle workflows
Event triggers
5k profiles (people + objects)
AI Agent with core execution skills
1 million emails per month
2 object types
Visual workflow builder
Email and community support
Basic data integrations

Full pricing Official Pricing

SparkPost features & plan notes

Deliverability analytics
Enterprise scale
Predictive signals
10 webhook endpoints
1,000 sending domains
Dedicated IPs (add-on)

Full pricing Official Pricing

How to compare email providers

Browse Email APIs pricing

Customer.io vs SparkPost — FAQ

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