MailerSend vs Customer.io: Email Marketing Comparison (2026)

An independent side-by-side comparison of MailerSend and Customer.io for email marketing buyers — pricing, features, integrations, and how often each is cited by major AI engines.

AI Citation Scorecard

How often each is cited by major AI engines when buyers ask email marketing questions. Last 90 days across ChatGPT, Perplexity, Gemini, Claude, and Copilot.

Tied overall — both at 0% cited across 10 probes.
ChatGPT
MailerSend
0 / 1 probes
0%
Invisible
Customer.io
0 / 1 probes
0%
Invisible
Perplexity
MailerSend
0 / 1 probes
0%
Invisible
Customer.io
0 / 1 probes
0%
Invisible
Gemini
MailerSend
0 / 1 probes
0%
Invisible
Customer.io
0 / 1 probes
0%
Invisible
Claude
MailerSend
0 / 1 probes
0%
Invisible
Customer.io
0 / 1 probes
0%
Invisible
Copilot
MailerSend
0 / 1 probes
0%
Invisible
Customer.io
0 / 1 probes
0%
Invisible
Scale:NoneLowFairStrongExcellent

Probes run hourly; each (engine × query) combo retests every ~3 days.

Pricing

MailerSend
Starting price
$6.30/month
Free tier
Yes
mailersend.com
Customer.io
Starting price
Free tier
customer.io

Key Features

MailerSend
  • 500 emails/month on Free
  • 100 API requests/day on Free
  • Unlimited users on Professional
  • 7 days API logs retention
Customer.io

Feature data is being indexed.

When to choose MailerSend

Choose MailerSend if your team prioritizes its strengths over Customer.io's. Full guidance populates as MailerSend's feature data is indexed.

When to choose Customer.io

Choose Customer.io if your team prioritizes its strengths over MailerSend's. Full guidance populates as Customer.io's feature data is indexed.

AI visibility profiles

Is one of these your brand?

Get the full report by email: every email marketing buyer question we ask, which engines name you, and who gets named instead.

MailerSend

mailersend.com

Customer.io

customer.io

Free check

Check any brand's AI visibility — free

We ask the buyer questions in this market across ChatGPT, Claude, Gemini, Perplexity and Copilot, and show you who gets named.

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