How we rank: Transactional email services

The Score (0–100) is a weighted sum of the factors below. Each factor is the weighted average of its metrics; each metric is calculated from one published fact. Missing facts score zero, and a service is ranked only when enough of its Score is backed by facts.

A service is ranked only when at least 70% of its Score is backed by verified facts.

← Best Transactional Email Services 2026: Email APIs and SMTP Relays Compared

Price 30%

The price in US dollars of 1,000 emails sent beyond the volume of the cheapest paid plan, or the pay-as-you-go rate per 1,000 emails, exactly as written on the official pricing page: $0 scores 100, $2 or more scores 0 (weight 2). A rate given per email is converted to 1,000 emails; we never divide a plan fee or a block price by the emails it includes. Also the price of the cheapest paid plan with monthly billing (or the fixed monthly deposit): $0 when the service is pure pay-as-you-go, $50 or more scores 0 (weight 2). A permanent free plan adds weight 1; a trial that ends does not count. The number of emails per month on that free plan adds weight 1 (log scale, 10,000 or more scores 100; 0 when there is only a trial; a limit stated only per day is not converted). Prices shown only in a currency chosen by our visitor location, only for annual billing or only after a script runs are left empty.

Metric	Rule
Price per 1,000 extra emails	Linear from 0 (100) to 2 (0) — lower is better
Cheapest paid plan, per month	Linear from 0 (100) to 50 (0) — lower is better
Permanent free plan	Yes = 100, No = 0
Free emails per month	Logarithmic, full score at 10,000

Sending features 30%

Whether you can send through an SMTP relay (weight 1) and through a documented API (weight 1), receive delivery, bounce and complaint events pushed to your own URL by webhooks or a push notification service (weight 1), get a dedicated IP address on some plan or as a paid add-on (weight 1), and receive inbound email into your app (weight 1). Also how many days the logs or copies of sent messages are kept on the cheapest paid plan (weight 1, log scale, 30 days or more scores 100). Beta and preview features do not count. A feature fact shows that the feature exists, not that the cheapest plan has it: check the note under each fact.

Metric	Rule
SMTP relay	Yes = 100, No = 0
Sending API	Yes = 100, No = 0
Event webhooks	Yes = 100, No = 0
Dedicated IP	Yes = 100, No = 0
Inbound email	Yes = 100, No = 0
Log retention on the cheapest paid plan	Logarithmic, full score at 30

Data protection and reliability 25%

Whether your account and message data can be kept in the European Union — the vendor stores it there or lets you choose an EU region for storage, not only for sending (weight 2); a GDPR data processing agreement (weight 1); a SOC 2 report (weight 1) and ISO/IEC 27001 certification (weight 1) for the vendor's own service, not only its data center; and the monthly uptime in a published SLA document or in the terms of service: 99% scores 0, 100% scores 100 (weight 1). Uptime figures from marketing pages or plan tables are not an SLA. We record the vendor's statement; we do not audit it.

Metric	Rule
Data kept in the EU	Yes = 100, No = 0
GDPR data processing agreement	Yes = 100, No = 0
SOC 2 report	Yes = 100, No = 0
ISO/IEC 27001	Yes = 100, No = 0
Uptime in a published SLA	Linear from 99 (0) to 100 (100)

Track record 15%

How long the service or company has been running: 20 years or more scores 100 (weight 2), and whether it publishes a public status page with incidents (weight 1).

Metric	Rule
Founded	Full score at 20+ years
Public status page	Yes = 100, No = 0