What is an email CMS?
An email CMS, or email content management system, holds a team's email templates and the rules for editing them.
A developer sets up each template once, marking which parts can change. Everyone else builds campaigns by filling in those parts as fields, then exports the finished HTML to the platform that sends it.
Modular Mail is one, built on a single attribute, data-mm, that marks the editable parts of your own HTML and exports finished campaigns to Salesforce Marketing Cloud, Braze, Marketo or any other ESP.
Updated 3 November 2026.
How an email CMS works
The template goes in once. Everything after that is content.
We used to wait three to five days for dev to update our email templates. Now my team builds campaigns in an afternoon. Same custom designs, zero technical dependency.
What an email CMS is not
The category is new enough that it gets confused with three older ones.
An ESP
An email service provider such as Klaviyo, Braze or Salesforce Marketing Cloud stores your lists, sends the email, runs the flows and reports on the results. An email CMS makes the email and hands the HTML over. You keep your ESP, and the CMS sits in front of it.
An email builder
Builders such as Stripo and Beefree give you a canvas and a library of blocks, and you design each email in the builder's own format. An email CMS starts from a template that already exists, usually in your own HTML, and only the parts a developer opened can change. Both can lock things; the difference is where the design lives. We compare the two inEmail CMS vs email builders.
A web CMS
WordPress, Contentful and the rest manage pages, and the analogy is where the name comes from: the design lives in a theme, the words live in a post. Email HTML is its own discipline, though, with tables, inline styles and fixes for Outlook, and a web CMS doesn't produce it well. An email CMS is built around those constraints.
Which email CMS tools are there?
Six platforms do the job this page describes, each for a slightly different team. The row that varies most is how your templates get in.
| Modular Mail | Knak | Stensul | Dyspatch | Taxi for Email | mailCMS | |
|---|---|---|---|---|---|---|
| Templates start from | Your HTML, marked with data-mm | Built in Knak's builder, or HTML imported and cleaned up | Modules built in Stensul | Modules written in DML, Dyspatch's markup | Your HTML with Taxi Syntax tags | A design system its specialists build for you |
| How marketers edit | Fill in fields, pick images from a shared media library, drag modules to reorder | No-code builder with brand guardrails | No-code builder with approved modules | No-code builder from modules | Pick modules, fill in content | Assemble modules, edit copy, images and links |
| Review and approval | Comments on the email or a part, review requests, approval on record | Comments and approvals in one place | Approvals with audit trail | Annotated comments, approval workflows | Permissions per team member | Proof links with comments and approval |
| Getting it to the ESP | Copy or download HTML, any ESP | One-click sync to Marketo, Eloqua, Marketing Cloud, Pardot and more; API | Deploys to Marketing Cloud, Journey Optimizer, Marketo, Eloqua, Responsys | Sync to Salesforce, HubSpot, Marketo; code export; API | Direct ESP connectors, or HTML download | Two-way with Braze, Marketing Cloud, HubSpot, Iterable; HTML export |
| Built for | Teams and agencies sending often from custom templates | Enterprise marketing ops | Large, regulated organisations | Transactional and marketing at scale | Brand and agency teams | CRM teams with a built-for-you design system |
| Pricing | Published | On request | On request | Published | On request | On request |
Details are from each platform's public website, checked 3 November 2026. Modular Mail isn't affiliated with any of them.
Sources: Platform websites, Knak, Stensul, Dyspatch, Taxi for Email, mailCMS.
What to expect inside an email CMS
It makes and approves the email. It doesn't send, doesn't replace your ESP's lists and flows, and in Modular Mail's case doesn't push to the ESP by API or keep a version history: you copy or download the HTML.
Templates and modules
The sections your emails are built from, kept in your HTML and maintained by a developer.
Content fields with rules
Text, image and link fields, with character limits and required fields where they're needed.
Approved options
Colour and choice fields offer the options a developer approved, and a style preset sets several styles from one choice.
Review and approval
Comments on the whole email or one part of it, and a record of who approved the campaign.
Products from your store
A product grid filled from Shopify, WooCommerce or WordPress, with prices and photos as the store has them.
HTML export
Copy or download the finished email for any ESP, with no integration to maintain.
Who an email CMS is for
The common thread is a team that sends often from custom templates its ESP's editor can't open.
Ecommerce and CRM teams
Several campaigns a week from templates an agency or a developer built, and a November that doubles the volume.
See how CRM teams use itAgencies
A workspace per client, built from your templates, so clients build campaigns while the design stays intact.
Modular Mail for agenciesEmail developers
Mark the HTML you already write and build modules instead of editing campaigns.
Modular Mail for developers64%
of email teams add a tool beside their ESP, and 76% do at large companies.Really Good Emails survey of 1,677 email professionals, 2025
Modular Mail is an email CMS
It works on the custom HTML templates you already have. Setup is done by us, your agency or your developer, and most teams are live within one to two weeks.
- Your existing HTML templates, with the editable parts marked
- Fields with limits and approved options
- Comments and approval on the email itself
- Copy or download HTML for Klaviyo, Braze, Salesforce Marketing Cloud or any ESP
- Product grids filled from Shopify, WooCommerce or WordPress
What is an email CMS?
An email CMS is a content management system for email. It holds your templates with their design fixed and their content as fields, so a team builds campaigns by filling in fields and exports the finished HTML to its ESP.
What does CMS stand for in email?
Content management system, the same as on the web. (If you were looking for a school district's or Medicare's email login, you've found the wrong CMS, sorry.)
Is an email CMS an ESP?
No. The ESP sends, segments, automates and reports. The CMS makes the email and exports the HTML to the ESP, so your lists and flows stay where they are.
Which email CMS platforms are there?
Modular Mail, Knak, Stensul, Dyspatch, Taxi for Email and mailCMS all manage templates with a fixed design and editable content and hand the result to an ESP. They differ in how templates get in (your own HTML, a builder, or a system built for you) and whether they push to the ESP or export HTML. Compare the six
How is an email CMS different from an email builder?
A builder designs each email from blocks in its own format. An email CMS starts from a template you already have and only lets the marked parts change. Read the full comparison
Can we use a web CMS like WordPress or Contentful for email?
You can store copy there, but neither produces email HTML, with its tables, inline styles and Outlook fixes. Teams that try end up with a developer rebuilding each email anyway.
What is a modular CMS?
A CMS that builds each page or email from reusable modules rather than one fixed layout. Every email CMS is modular in this sense: the template is a set of modules, and a campaign is the modules it needs, in order. What are modular email templates?
Do we need a developer to use an email CMS?
For setup, yes: someone marks the template and sets up the fields, which we can do for you. Day to day, marketers build campaigns without touching code.
Which ESPs does an email CMS work with?
Any that accepts HTML. Modular Mail exports to Klaviyo, Braze, Salesforce Marketing Cloud, HubSpot, Marketo, Iterable and the rest, with no integration to install.
What does an email CMS cost?
Modular Mail starts at £149 a month for 2 editors, and the Team plan is £360 a month for 10. Reviewers are free. Enterprise, for agencies and larger companies, starts at £10,000 a year. See pricing
See your own email in Modular Mail.
Send us a recent campaign. We'll rebuild it before the call, so you can see exactly how your team would work.