Transactional email cost: what a small site really pays

Quick answer

Setting up transactional email properly is the main cost (our API integration work starts at £499); the service itself usually costs nothing to about $15 a month for a small website. Free tiers cover low volumes, and at the time of writing Mailgun and Postmark both list paid plans from $15 a month for 10,000 emails.

Transactional emails are the messages your website sends because someone did something: an order confirmation, a password reset, a booking reminder, the copy of a contact form that lands in your inbox. When they fail, customers think you never received their order, and you never see the enquiry. Most small sites start by sending them straight from the web server, which works until it quietly stops. A dedicated sending service fixes that, and this guide sets out what one costs, what drives the price, and what a realistic budget looks like for different kinds of site.

What you are paying for

A transactional email service, sometimes called an email API or SMTP relay, takes the messages your website generates and delivers them from infrastructure built for it. You pay for three things:

• Volume. How many emails you send a month. This is the main price driver.
• Deliverability features. Authentication, reputation management, bounce handling and logs that show whether each message arrived.
• Extras. Dedicated IP addresses, longer log retention, more team members, inbound email processing and support levels.

It is a different job from a newsletter tool. Our guide to transactional versus marketing emails explains why they are best kept separate, and why mixing them can drag down delivery of the messages that matter most.

Published prices from the main services

These figures were read from each provider’s own pricing page at the time of writing, November 2026. They are in US dollars, as listed, and exclude VAT. Check the current page before you sign up, because providers change plans often.

Sources: Mailgun pricing, Postmark pricing and Amazon SES pricing. Mailgun also lists Foundation at $35 a month for 50,000 emails and Scale at $90 a month for 100,000; Postmark lists Pro at $16.50 and Platform at $18 a month at the 10,000 level. Amazon lists a standard dedicated IP at $24.95 a month.

How much email does a small site actually send?

Less than most people think. Work it out from events rather than guessing:

• A brochure site with a contact form: one or two emails per enquiry (the notification to you, perhaps an auto-reply). Even a busy month is usually a few hundred.
• A booking site: a confirmation, a reminder and perhaps a follow-up per booking. A hundred bookings a month is around three hundred emails.
• A small online shop: order confirmation, dispatch notice, perhaps a delivery update and an account email. Four or five per order is typical.
• A membership or software product: logins, alerts and notifications can add up quickly. This is where volumes reach the paid tiers.

So most small business websites sit comfortably within free tiers or the lowest paid plan. The price matters less than choosing a service with good delivery and setting it up properly.

The costs people forget

• Set-up time. Connecting the service to your website, verifying your domain and adding the authentication records to your DNS. Done well, it is a short job; done badly, emails go to spam.
• DNS records. SPF, DKIM and DMARC records tell inbox providers your emails are genuine. Our guide to business emails going to spam explains each one.
• Monitoring. Somebody should glance at the logs occasionally and notice when bounces spike or a form stops sending.
• Templates. Branded order and booking emails look far more trustworthy than plain defaults, and they take design time.
• Dedicated IPs. Rarely needed at small volumes. Shared sending from a good provider is usually better until you send large volumes consistently.

Sending from your server versus paying for a service

Many websites, especially WordPress sites, send email straight from the web server by default. It costs nothing extra, which is why it is so common. The problem is that a shared web server is not a trusted email sender. Its address is shared with hundreds of other sites, some of which send spam, and it often lacks the authentication records inbox providers now expect. The result is email that arrives late, lands in spam or silently disappears, and you have no log to prove what happened.

A sending service costs little or nothing at small volumes and changes three things: messages go out from addresses with a good reputation, they are signed with your domain’s authentication records, and every message is logged so you can see whether it was delivered, bounced or opened. For any site where a missing email means a lost order or a missed enquiry, that is cheap insurance.

Choosing between providers

At small volumes, price differences between the main services are small, so choose on other grounds:

• Ease of set-up. Some services have ready-made connectors for WordPress, WooCommerce and common booking tools; others expect a developer.
• Logs and support. How long are message logs kept, and can you reach a person if delivery breaks?
• Separation of streams. Some providers let you keep transactional and marketing email on separate streams, which protects your order emails.
• Data location. Check where message data is processed and stored, and note it in your privacy notice.
• Room to grow. Look at the price of the next tier up, not just the entry plan.

Cost by situation

A worked example

A small online shop in Bath sells handmade leather goods and takes about 300 orders in a busy month. Each order triggers an order confirmation, a dispatch email and an occasional account email: call it four per order, so around 1,200 transactional emails a month, plus a few hundred contact-form and password-reset messages. That fits within an entry paid plan at either Mailgun or Postmark at the published prices above, with room to grow, and Amazon SES at pay-as-you-go rates would cost very little in sending fees, though it asks more of whoever sets it up.

The bigger line in the budget is the one-off work: connecting the shop to the service, setting up SPF, DKIM and DMARC, designing branded order emails and testing every message the shop sends. After that, the running cost is small and predictable.

Signs you need a sending service now

• Customers say they never received an order or booking confirmation.
• Contact form enquiries arrive in your spam folder, or not at all; our guide to a contact form not working covers the checks.
• Your host limits how many emails the server can send each hour.
• You have no record of which emails were sent and delivered.

What we charge to set it up

Connecting a website or app to a transactional email service is integration work. Our API development and integration starts at £499 and covers connecting your systems so messages send reliably and can be checked. If the shop itself needs building, our e-commerce website starts at £499 for up to 20 products, and we can quote the email set-up alongside it. If you are also budgeting for mailboxes and newsletters, see our guides to business email set-up costs and email marketing costs. Every Luxbranding price is on our pricing page.