HubSpot Transactional Email Add-on: Pricing, Limits, and Alternatives

The HubSpot transactional email add-on is a paid extra for Marketing Hub Professional and Enterprise. HubSpot’s product and services catalog lists it at $600 per month. It lets you send receipts, account updates and other relationship-based messages from a dedicated IP address, either from the HubSpot editor or through the Single-send API or SMTP API. HubSpot does not publish how many IPs you get or any sending cap for it. Everything about HubSpot below was checked on October 8, 2026.

If you are not on Marketing Hub Professional or Enterprise, you cannot buy it at all. In that case, or if your volume is high, a dedicated provider from the transactional email services shortlist is usually simpler. The decision table below sorts out which case you are in.

What the add-on does that regular HubSpot email does not

Regular HubSpot marketing email is promotional and goes out under subscription rules. HubSpot’s knowledge base says that “Marketing emails are promotional materials, such as newsletters, offers, or blog posts.” Transactional email is the other category, and the add-on is what unlocks sending it.

Three things change with the add-on:

• Subscription rules do not apply. HubSpot says transactional emails “can be sent to contacts regardless of subscription preferences, quarantine status, previous bounces, or non-marketing contact status. Only contacts with a previous bounce as an unknown user will be dropped from transactional emails.”
• A dedicated IP. The product page states that “The dedicated IP will only send transactional emails.” Marketing email stays on shared infrastructure unless you also buy the separate Dedicated IP add-on, which the catalog lists at $300 per month. See dedicated IP vs shared IP for what that trade-off means for reputation.
• Two ways to send from code. The Single-send API and SMTP API, covered below.

What counts as transactional. HubSpot defines transactional emails as “relationship-based emails” that are “generally triggered by an action taken by the recipient,” such as an account signup, purchase receipt, invoice or password change. For content, it recommends that you “limit the content of a transactional email to focus on an already agreed upon transaction or updates on an ongoing transaction,” and says your legal team is the best resource for compliance advice. HubSpot does not publish a hard prohibition on marketing content; it leaves that to the laws of the recipient’s country. For the general distinction, see transactional vs marketing email.

Requirements, price and limits

Item	What HubSpot publishes	Source
Eligible products	Marketing Hub Professional and Enterprise	Knowledge base, product page, catalog
Price	$600 per month. No other billing terms listed for the add-on	Catalog
How to buy	Contact your Customer Success Manager or sales representative. No self-serve checkout is described	Knowledge base, product page
Dedicated IPs included	Not published (“a dedicated IP” is the only wording)	Product page
Sending methods	In-app transactional email, Single-send API, SMTP API	Developer docs
Sending limits for transactional email	Not published	Product page, knowledge base
Domain setup	The From domain must be connected as an email sending domain in HubSpot (stated for the SMTP API)	Developer docs
IP warmup	Transactional IPs do not go through HubSpot’s automated IP warm-up. You may need to warm a new one manually	Product page

Checked on October 8, 2026. The sources are HubSpot’s Send transactional emails article (last updated September 29, 2026), the transactional email product page, the products and services catalog and the transactional email API guide.

The warmup row matters in practice. The product page says you “may need to manually warm up a new transactional IP” before sending high volume that is not triggered by contact actions, and points you to your customer success manager for advice. The mechanics are covered in our IP warming guide.

One limit HubSpot does publish is for marketing email, not transactional: the catalog says send limits are multiples of your contact tier, 10 times for Professional and 20 times for Enterprise per calendar month. Whether transactional sends count toward those numbers is not stated, so ask your HubSpot rep before you plan volume around it.

How sending works: Single-send API vs SMTP API

HubSpot’s developer guide describes three methods. The in-app method uses the email editor with the subscription type set to Transactional. The two API methods differ in who owns the template.

	Single-send API	SMTP API
Template lives in	HubSpot’s email editor	Your own system
You send	A JSON POST with the email ID and recipient	Mail over SMTP using token credentials
Contact records	Created automatically if no contact matches the email address	Optional, set by createContact on the token
Best for	Receipts and notices that marketers design in HubSpot	Apps that already build their own email and want HubSpot tracking

Single-send API. You build and publish a template in HubSpot, copy its email ID, and POST to /marketing/transactional/2026-09/single-email/send. The required scope is transactional-email. At minimum the message object needs a to field. This body is adapted from HubSpot’s guide:

{
  "emailId": 4126643121,
  "message": {
    "to": "[email protected]",
    "sendId": "6"
  },
  "customProperties": {
    "purchaseUrl": "https://example.com/link-to-product",
    "productName": "vanilla"
  }
}

sendId prevents duplicates: HubSpot says “Only one email with a given sendId will be sent per account.” Values in customProperties are used only inside the email, referenced in the template as {{ custom.NAME_OF_PROPERTY }}. HubSpot also warns that it does not save the HTML or JSON you send, so add a BCC if you need a copy. The docs list a rejection for role-based recipients such as noreply, postmaster and security, which is worth knowing if you send to shared mailboxes.

SMTP API. You create a token with POST /marketing/transactional/2026-09/smtp-tokens/, using createContact and campaignName. The response includes the id (your SMTP username) and a password that “can only be retrieved at the time of creation.” The server is smtp.hubapi.com (smtp-eu1.hubapi.com for EU accounts), on port 25 or 587 for STARTTLS or 465 for direct TLS. Tokens created through the API expire after 12 months, while tokens created in the HubSpot account do not expire automatically. If you want the background on this style of sending, see SMTP relay.

The docs show a current dated version path (2026-09) and mention no deprecations in the transactional email guide.

When the add-on is worth it, and when it is not

This is reasoning built on the published facts above, not a HubSpot recommendation.

Situation	Recommendation	Reason
On Marketing Hub Professional or Enterprise, low to moderate volume, marketers own the templates	Add-on is a reasonable fit	Templates, send history and contact timeline stay in one tool
Not on Marketing Hub Professional or Enterprise	Use a dedicated provider	The add-on is not available to you
High-volume product email such as one-time codes and notifications	Use a dedicated provider	$600 per month is a fixed cost, and sending limits are unpublished, so you cannot size it
Engineers own the email code and templates live in the repo	SMTP API or a dedicated provider	The Single-send API ties template changes to the HubSpot editor
You need guaranteed IP count or a contractual volume cap	Ask HubSpot for it in writing	Neither is published

The decision rule: buy the add-on when your transactional volume is modest, you already pay for an eligible Marketing Hub tier, and keeping receipts and notices on contact timelines is worth $600 per month. Otherwise, price a dedicated provider first.

Alternatives for transactional sending

Prices below come from each vendor’s pricing page on October 8, 2026. They change often, so confirm before buying. The rows are not like for like: each vendor bills differently and sets its own conditions on dedicated IPs.

Provider	Billing unit and entry paid price	Dedicated IP	More detail
Postmark	Monthly plan: Basic is $15.00 per month for 10,000 emails	Add-on from $50 per month per IP, for customers sending 300,000 emails per month or more, on Pro plans or higher	Postmark pricing
Amazon SES	Per email: $0.10 per 1,000 emails on pay-as-you-go pricing	Standard dedicated IPs at $24.95 per month per IP	Amazon SES alternatives
Resend	Monthly plan: Pro is $20 per month for 50,000 emails	Add-on at $30 per month, for customers exceeding 3,000 emails per day on the Scale plan	Resend pricing
Mailgun	Monthly plan: Basic starts at $15 per month for 10,000 emails	Offered on higher plans, with terms that differ by plan; confirm on the pricing page	Mailgun pricing

Sources: Postmark, Amazon SES, Resend and Mailgun. For a broader comparison, see the guide to transactional email APIs.

Teams that move transactional mail off HubSpot usually keep HubSpot as the CRM. One option HubSpot documents itself is the SMTP API, which lets your own system send while HubSpot adds tracking and can create contacts. Whether a given third-party provider can log sends to the contact timeline depends on its integration, so check that before you migrate.

Frequently Asked Questions