SMTP (now part of Ziff Davis/Martech) offers affordable and reliable SMTP relay and email delivery services that enable you to send and track high-volume emails effortlessly. SMTP helps businesses send billions of emails every month to their customers using their secure, trusted, and scalable email delivery platform. For over two decades, businesses have relied on their speedy deliverability rates and reputation among mailbox providers. In addition, you can optionally add SMTP Reputation Defender, which proactively monitors your email list health and safeguards your domain and IP reputation by suppressing invalid email addresses before you send.

SMTP claims ISPs believe them to be one of the internet's most reliable and trusted senders. They maintain an impeccable reputation among mailbox providers by proactively vetting out spam and maintaining high delivery rates. Their highly responsive infrastructure ensures virtually no latency and over 99% system uptime.
Pros and Cons
Ensures your emails aren't mixed up with spam
Easy to set up
Helpful customer service
No free (or very cheap) plan for those with modest needs
Reporting not as in-depth as some competitors
Email-only – no recognition of SMS
Best for: Small to medium-sized businesses (SMBs), although also viable for larger companies
Ease of Use
Overall Score:

SMTP offers powerful email delivery services that enable you to send and track high-volume emails effortlessly. You can integrate and start sending in minutes. SMTP is a suite of email delivery, relay and API solutions designed to be reliable, scalable, and secure.

Features include:

Transactional email service

Transactional emails are important to your customers and your business. SMTP will deliver the messages that your customers most want to receive. Typical transactional emails include account-related emails (password resets, privacy policy updates, account updates), eCommerce-related emails (purchase receipts, shipping updates, back-in-stock notices), product notifications, and billing emails. SMTP is built to handle sending billions of emails daily, SSL encrypted with support for DKIM and SPF.

Email Relay API

SMTP built its API infrastructure with flexibility and ease of integration in mind. Get up and running within minutes with their email relay settings or API. Their email relay API makes integrating email capabilities into your product a breeze.

Email Delivery Suite

SMTP offers a suite of email delivery services and tools that get your messages into subscriber inboxes. They proactively vet out spam and maintain high delivery rates. Their highly responsive infrastructure ensures virtually no latency and over 99% system uptime.

Managed Migration Service

Turn email into revenue using expert guidance, inbox placement consulting, account management, and custom template design resources. SMTP’s email delivery experts have over two decades of experience helping thousands of businesses with their email needs. Effortlessly move your operations from other providers without disrupting your business using SMTP’s guide onboarding service. They have custom-built templates for various platforms, list validation, and guided onboarding. In addition, a dedicated account manager will personally look after your account’s health and delivery performance and review your incremental email-driven business growth.

Reputation Defender

Reputation Defender uses Big Data queries and advanced algorithms to catch bad email addresses before you send to them. You can enable Reputation Defender at sign-up or by talking to SMTP. You simply leave Reputation Defender on, and it does its thing.

Pricing / month

Pricing /month
SMTP offers 5 email plans, and you can customize a plan that fits your specific email volume, integration, or other business needs. They don't offer a free plan, although they will give you a 30-day free trial. All plans are full-featured (with minor variations) and differ based on email count.

Essential: $25/mo for up to 50,000 emails (then $0.000625 per additional email)
Starter: $80/mo for up to 100,000 emails (then $0.001 per additional email)
Growth: From $300/mo for up to 500,000 emails (then $0.00075 per additional email)
Business: From $500/mo for up to 1,000,000 emails (then $0.000625 per additional email)
High Volume Senders: Custom for more than 250,000,000 emails

Reputation Defender is an add-on costing $5-$100/mo depending on your plan (20% of plan cost)

Date founded



Ottawa, Ontario, Canada (HQ); Raleigh, North Carolina, United States; Dallas, Texas, United States; Newcastle upon Tyne, England; Kiev, Ukraine; Odessa, Ukraine

Company size

51-200 employees


Email Marketing


List Management

Reputation Defender


Transactional emails

Managed email delivery

SMTP for developers


API Integrations

Activity Tracking

Email Management


Reporting & Analytics