The best SMTP relay services of 2026

SMTP2GO is the relay we would hand to someone whose website sends contact form replies, order confirmations and password emails, and who wants those emails to stop landing in spam. You create an account, set up the domain you send from, then paste the SMTP details into your site, app or email program. On WordPress, SMTP2GO's own plugin replaces WordPress's built-in mail function, so every outgoing message goes through SMTP2GO's API, and SMTP2GO also publishes setup guides for WooCommerce, FluentSMTP and Post SMTP.

The free plan covers 1,000 emails a month with no credit card. Paid plans are priced by volume: $15 a month for 10,000 emails, $30 for 50,000 and $75 for 100,000, and paying yearly gets you two months free. Support by ticket, chat and phone is part of every plan, though free accounts keep chat and phone for their first 14 days only. Paid plans keep 30 days of email reports, and a dedicated IP comes with the Professional tier from 100,000 emails a month. SMTP2GO offers a full refund if you cancel within 30 days.

The weak spot is price at volume. At 100,000 emails a month SMTP2GO costs about twice what SendGrid Essentials or Resend Pro charge and several times the Amazon SES rate, so it suits steady small senders better than an app that is growing fast.

Amazon SES is the cheapest way to send a lot of email, as long as someone on your team is comfortable in the AWS console. Pay-as-you-go sending costs $0.10 per 1,000 emails, so 100,000 emails come to about $10, plus $0.12 per GB of attachments. AWS also sells bundled plans: Essentials at $0.16 per 1,000 with no monthly fee, Pro at $105 a month plus $0.22 per 1,000 with managed dedicated IPs and email validation included, and Enterprise at $500 a month plus $0.23 per 1,000. A standard dedicated IP costs $24.95 a month, and new AWS customers get up to $200 in Free Tier credits.

Setup takes longer than anywhere else in this guide. Every new account starts in a sandbox, where you can send only to addresses you have verified, up to 200 messages a day and one a second. To leave it, you request production access and describe the mail you send; AWS says it gives an initial response within 96 hours, and it asks you to confirm you have a process for handling bounces and complaints. You then create SMTP credentials, which are separate from your AWS access keys and differ for each region, and point your app at that region's SMTP endpoint.

The low headline price covers sending only. On pay-as-you-go, the deliverability dashboard (Virtual Deliverability Manager) costs another $0.07 per 1,000 emails, and acting on bounces and complaints is up to you.

Postmark suits software companies whose most important emails are the ones users are waiting for: sign-in links, password resets and receipts. It sends those through a transactional message stream and sends bulk mail, such as product updates, through a separate broadcast stream on its own pool of IP addresses. Postmark says the two kinds of traffic do not mix, so a newsletter that draws complaints does not share addresses with your login emails. You can connect over SMTP at smtp.postmarkapp.com on port 587 with TLS, or use the API.

The free plan gives you 100 emails a month for testing, and it does not expire. Basic costs $15 a month for 10,000 emails, with extra emails at $1.80 per 1,000. Pro costs $16.50 with extras at $1.30 per 1,000, and Platform costs $18 at $1.20 per 1,000. The higher plans also raise the number of sending domains (5 on Basic, 10 on Pro, unlimited on Platform) and let you keep message history beyond the standard 45 days, up to 365, with a retention add-on from $5 a month. Dedicated IPs start at $50 a month, but only on Pro or higher and only once you send 300,000 or more emails a month.

Past the first 10,000 emails Postmark costs more per email than SendGrid or Resend, so it makes sense when keeping app mail separate matters more to you than the bill.

Brevo, the company formerly called Sendinblue, gives you an SMTP relay and an email marketing app in one account. That makes it a sensible pick for a small business that wants its website's order and contact emails to go out through a proper relay and also wants to send a monthly newsletter, without paying two vendors. In Brevo's settings you generate an SMTP key (Brevo is clear that an API key will not work here) and connect on port 587 or 2525, or on 465 with SSL or TLS.

The free plan sends up to 300 emails a day once Brevo approves your account for sending, and it has no end date. Paid marketing plans start at $9 a month on Starter and $18 on Standard, each with 5,000 emails a month, and the price rises with your monthly volume. Paying yearly takes off 10%. Dedicated IPs are available, but the pricing page does not give a price for them.

Three hundred a day is plenty for a contact form and tight for a store sending order emails and a newsletter from the same account. Developers should also know that Brevo's SMTP relay does not support batch sending; Brevo points you to its batch API for that.

SendGrid, now part of Twilio, is the safe choice for an app that sends tens of thousands of emails today and expects millions later, because its price steps are published all the way up. Every Email API plan includes SMTP and API sending. Essentials costs $19.95 a month for 50,000 emails or $34.95 for 100,000. Pro starts at $89.95 for 100,000 emails and climbs to $249 for 300,000, $499 for 700,000, $799 for 1.5 million and $1,099 for 2.5 million. Pro includes a dedicated IP and lets you buy more, and Premier is priced to order.

New accounts get a 60-day free trial with no credit card, limited to 100 emails a day. That is enough to connect and test your app, but you will be on a paid plan before you go live.

For 50,000 to 100,000 emails a month without a dedicated IP, Essentials is one of the cheapest managed options here. The step from $34.95 to $89.95 when you need a dedicated IP is steep, and Twilio sells expert services and personalized support as paid extras rather than including them.

Resend is aimed at developers, and the free plan shows it: 3,000 emails a month (up to 100 a day), 3 domains and SMTP included. Connecting needs the host smtp.resend.com, the user name resend and an API key as the password, on port 465 or 2465 for SSL, or 25, 587 or 2587 with STARTTLS. Resend lists integrations for Supabase, Auth0, NextAuth, Django, Rails and WordPress, among others, so the sign-up and login emails those tools send can go through Resend with a few settings.

Paid plans are easy to read. Pro costs $20 a month for 50,000 emails or $35 for 100,000, with 10 domains and extra emails at $0.90 per 1,000. Scale starts at $90 for 100,000 emails with up to 1,000 domains and runs to $1,150 for 2.5 million. A dedicated IP costs $30 a month, and only Scale customers sending more than 3,000 emails a day can add one.

If nobody on your team writes code, SMTP2GO or Brevo will be easier to live with. For a developer choosing between Resend Pro and SendGrid Essentials, the prices are close, and Resend's free tier is the bigger one.

Mailjet, part of Sinch, combines a campaign editor with an API and SMTP relay, and the relay is part of the free plan. Free sends up to 6,000 emails a month, capped at 200 a day, for up to 1,000 contacts. That is less than Brevo's 300 a day, so Mailjet's case rests on its low paid prices more than its free plan.

Paid plans stay cheap for small senders. Starter costs $9 a month for 8,000 emails, Essential costs $19 for 15,000 and Premium costs $29 for 15,000, with prices rising by volume. Essential is the first plan without the Mailjet logo in your emails. Paying yearly takes off 10%.

Support is where Mailjet holds back on the lower plans. Starter gets online support, and phone and chat support come with Premium from the 50,000-email tier. A dedicated IP is available on Premium from 100,000 emails a month, on request. If you mainly send from code and expect 100,000 emails a month, compare SendGrid's and Resend's published prices first.

Elastic Email's Email API plans charge a flat monthly price for a block of emails, and the entry price is low. Starter costs $19 a month for up to 50,000 emails and includes the Email API and SMTP relay. Pro starts at $49 a month for the same volume and adds inbound email processing, webhooks and subaccounts, which matter once you run sending for several clients or apps. Both plans scale on a slider up to 10 million emails a month.

The free option lets you try the Starter features with a limit of 100 emails a day, for up to 3,000 emails a month. Paid add-ons include private IPs and dedicated support, which the page lists at $50 and $100 a month.

At 50,000 emails Elastic Email undercuts SendGrid Essentials by about a dollar, so the price alone is not a reason to switch. It is a reasonable pick if you want an SMTP relay plus a marketing editor from one company and don't want to set up AWS for Amazon SES.

Platformly is an email marketing and automation platform with a transactional email module, and it fits one kind of buyer in this guide: a business that wants receipts, password resets and account emails run from the same account as its newsletters and automations. The module gives you an SMTP relay, an API and templates for those messages, and they go to the same contact records your marketing uses.

Mail can go out through Platformly's own sending or through your own SMTP server or an account you already have with Amazon SES, SendGrid, Mailgun, Postmark, Mailjet or Elastic Email. So you can keep a relay from this guide for delivery and manage your templates and campaigns in Platformly. Suppression lists and bounce handling are built in, and Platformly helps you set up domain authentication.

The rest of the account is what the relays above don't offer. Sales imported from Stripe, Paddle, Shopify and WooCommerce are matched to the email, link or source that brought each customer in, and an AI assistant helps write, segment and automate, with a person approving anything that sends.

The specialists go deeper on delivery itself. Postmark keeps app and bulk mail in separate streams by default, and several services above offer dedicated IPs at set volumes. We haven't listed a free allowance or a price per 1,000 emails for Platformly; see Platformly's site for current plans.

Choose it if you want app email and marketing email in one account, with revenue tracked back to each email.

Skip it if you only need SMTP login details for a website or app. SMTP2GO or Amazon SES does that with less to set up.