SendGrid alternatives for transactional email

If you are looking for a SendGrid alternative for transactional email, five are worth a test: Postmark, Resend, Mailgun, Amazon SES and Boundry. They differ on how they price (a flat monthly plan, a per-thousand rate, or a plan plus overage), how long the free tier lasts, whether a dedicated IP is included, and where your data can be kept. This page compares them on those points using each provider's own pricing page, read on 27 October 2026.

We make Boundry, so it is in the list, and we say where it is not the right pick. Boundry's row comes from our own pricing and docs. Every other row comes from the provider's page, linked in the section for that provider. Prices change, so check the linked page before you buy.

The comparison at a glance

• SendGrid: free trial of 100 emails a day for 60 days; Essentials from $19.95 a month, Pro from $89.95 a month; one dedicated IP listed as included on Pro and Premier; EU data residency listed on paid plans.
• Postmark: free plan of 100 emails a month; paid plans from $15 a month for 10,000 emails, with overage of $1.80 per 1,000 on that plan; dedicated IPs from $50 a month per IP, for senders of 300,000 or more emails a month on Pro or higher; no data region statement on the pricing page.
• Resend: free plan of 3,000 emails a month with a limit of 100 a day; Pro from $20 a month for 50,000 emails; a dedicated IP as an additional $30 a month on Scale or higher, for senders of more than 3,000 emails a day; multi-region listed, with the locations not given on the pricing page.
• Mailgun: free plan of 100 emails a day; Basic from $15 a month for 10,000 emails; Foundation $35 a month for 50,000 emails, where a dedicated IP is available but not included (included from Scale, $90 a month for 100,000 emails); US or EU sending from one account.
• Amazon SES: Essentials rate of $0.16 per 1,000 emails for the first 10 million a month, Pro with a $105 monthly charge and Enterprise with a $500 monthly charge per account per region, and an à-la-carte outbound rate of $0.10 per 1,000; managed dedicated IPs at $15 a month per account plus $0.08 per 1,000 emails for the first 10 million a month (included on Pro and Enterprise); new AWS customers get up to $200 in free tier credits.
• Boundry: Sandbox free with 3,000 emails a month; Developer $25 a month for 50,000 emails; Business $250 a month for 500,000 emails; each project bound to one region, with Sydney the only live region today.

SendGrid, for reference

SendGrid is Twilio's email product. Its Email API pricing page lists a free trial ("100 emails/day for 60 days", no credit card), then Essentials from $19.95 a month and Pro from $89.95 a month, with Premier on custom pricing. It says pricing depends on monthly volume and features. It lists suppression management on all plans, event webhooks (1 on the trial, 2 on Essentials, 5 on Pro and Premier), an inbound parse webhook on Pro and Premier, and EU data residency on paid plans.

The page these figures come from. SendGrid Email API pricing

Postmark

Postmark's pricing page lists a free plan of 100 emails a month that it says does not expire, then Basic at $15 a month, Pro at $16.50 a month and Platform at $18 a month, each starting at 10,000 emails a month. Overage is $1.80, $1.30 and $1.20 per 1,000 emails respectively. Message retention is 45 days, and Pro and Platform can extend it up to 365 days as an add-on. Dedicated IPs are offered to senders of 300,000 or more emails a month on Pro or higher, from $50 a month per IP. The page does not state a data region.

It suits you if you want a plan priced by volume and a free plan that does not run out. The free plan includes 100 emails a month and allows no overage. Check whether that covers your expected volume.

The page these figures come from. Postmark pricing

Resend

Resend's pricing page lists transactional plans of Free ($0, 3,000 emails a month, 100 a day), Pro ($20 a month for 50,000 emails, or $35 for 100,000), Scale ($90 to $1,150 a month by volume) and Enterprise. Paid plans have no daily limit and offer pay-as-you-go overage. A dedicated IP is an additional $30 a month on Scale or higher, and Resend's dedicated IP page requires more than 3,000 emails sent per day. Webhook endpoints are 1 on Free, 5 on Pro and 10 on Scale. Marketing email is priced separately by contacts. The page says multi-region is available; it does not name the regions.

It suits you if you want a free allowance of 3,000 emails a month to build against. If you need to know which country the data sits in, ask Resend, because the pricing page does not say.

The page these figures come from. Resend pricing

Mailgun

Mailgun's pricing page lists Free (100 emails a day), Basic from $15 a month (10,000 emails), Foundation at $35 a month (50,000 emails) and Scale at $90 a month (100,000 emails), plus Enterprise. Foundation and Scale have a one-month free trial. The page distinguishes dedicated IP access at 50,000 emails from inclusion at 100,000 emails and above, so Foundation at $35 does not include one; Scale does, and extra IPs are $59 a month each. It says you can "send email through the US or the EU from a single account" and that your data can remain in the region you choose.

It suits you if you want a dedicated IP included from the 100,000-email Scale plan, or you want to choose between the US and the EU on one account.

The page these figures come from. Mailgun pricing

Amazon SES

Amazon SES is priced mainly per email. Its pricing page lists $0.16 per 1,000 emails on the Essentials plan up to 10 million a month, $0.22 on Pro (with a $105 monthly charge per account per region) and $0.23 on Enterprise (with a $500 monthly charge per account per region) at the same volume, and an à-la-carte outbound rate of $0.10 per 1,000. Outgoing data is charged at $0.12 per GB (the page calls it attachment data, and its examples apply it to message size). Managed dedicated IPs are an add-on on Essentials at $15 a month per account plus a per-email fee: $0.08 per 1,000 emails for the first 10 million a month, $0.04 from 10 to 50 million and $0.02 from 50 to 100 million, with above 100 million by contact. Pro includes one managed dedicated IP and Enterprise includes twelve. Standard dedicated IPs are $24.95 a month per IP. New AWS customers get up to $200 in free tier credits, and the page says credits expire within 12 months.

It suits you if you already run on AWS, send high volume and are happy to do the integration work yourself, such as configuring SES event destinations to receive delivery events. The listed price per email is low, and the setup work falls to your team.

The page these figures come from. Amazon SES pricing

Boundry

Boundry is a regional transactional email API. Each project is permanently bound to one region and its regional application storage, and Sydney (ap-southeast-2) is the only live region today. Plans are Sandbox ($0, 3,000 emails a month, 1 sending domain), Developer ($25 a month, 50,000 emails, 10 sending domains) and Business ($250 a month, 500,000 emails with graduated usage pricing up to 2 million, 1,000 sending domains, 3 active regions), plus Enterprise on custom terms. Prices are in US dollars. Sandbox and Developer pause sending at the included volume until you upgrade or the next billing month starts.

Boundry has signed webhooks for delivery, bounce and complaint events, idempotent sends, SDKs for JavaScript/TypeScript, Python, Go and PHP (Ruby is a preview), and a remote MCP server for AI agents. It is an HTTP API; the documented interface is the API and SDKs.

Boundry is not the right pick in several cases. Paid checkout is not yet self-serve. Sydney is the only live region, so if you need the US or EU today, use a provider that lists them. Configurable retention is not yet enforced and inbound email is not generally available. The Sydney boundary excludes recipient mailbox routing, Cloudflare may be in the network path, identity and organisation data is processed centrally, and backup and observability evidence is still incomplete. We publish no deliverability rates or uptime figures, and we do not have the track record of the older providers on this list. If you need a dedicated IP, a long-established sender reputation, or the lowest price per email at very high volume, look at the others first.

It fits if you want a project's message operations and configured application storage kept in Sydney, one fixed region per project that cannot be changed by accident, and you want a small API that an engineer or an AI agent can set up from code.

What the Sydney boundary covers, what sits outside it and what evidence is outstanding. Australia region page

Plans, limits and the volume estimator. See Boundry pricing

How to choose

• You want a per-email rate and already use AWS: test Amazon SES.
• You want a free allowance to build against: compare Resend's 3,000 emails a month with Boundry's Sandbox, which is also 3,000.
• You need a dedicated IP: SendGrid lists one as included on Pro and Premier, and Mailgun includes one from Scale at 100,000 emails.
• You need to choose between the US and the EU: Mailgun and SendGrid list EU options on their pricing pages.
• You need a project's message operations and application storage kept in Sydney, with a region fixed per project: test Boundry, and read the exceptions above and the Australia region page first.
• You send a small volume and want the plan that does not expire: Postmark's free plan is 100 emails a month with no expiry.

Whichever you pick, send a test through each shortlisted provider before moving production traffic. The checklist below covers the tests worth running: retries, domain verification, webhooks, the cap and the data location.

Eight checks to run on any provider. Choosing a transactional email API: a checklist

Plan by plan, with a cost at four volumes. Resend pricing

If emails from your new provider land in spam, start here. Why emails go to spam and how to stop it

If you are new to the term. What is transactional email?

Where your email data is stored and what sits outside the boundary. Data sovereignty in Australia

Sources: the five pricing pages linked above and SendGrid's Email API pricing page, all read on 27 October 2026. Prices checked 27 October 2026. Boundry facts are from boundry.dev pricing and docs.