Email template builder

Design reusable branded emails with the drag-and-drop block builder.

The email template builder creates reusable designs for email blasts and flow emails. Build the layout once (logo, colors, footer) and campaigns start from a polished base instead of a blank canvas.

Create one from Templates → New template → Email.

Email type

The left panel starts with an Email type choice:

• Design: the drag-and-drop block builder. Best for newsletters, promos, anything with layout.
• Rich text: a simple formatted note that renders like a personal email. An Include footer toggle appends your business name and contact details above the unsubscribe link.

Blocks

In Design mode, the Email content blocks palette offers:

Drag a block onto the canvas (or click to add), then reorder by dragging. Select any block to edit its properties in the right-hand inspector: the Header exposes logo, height, and alignment; the Footer takes your phone, address, website, and social URLs.

Header and Footer blocks pre-fill from your workspace settings (name, logo, phone, address, socials), so branding is automatic.

Dark mode colors

Every email you send automatically gets a readable dark-mode version. Recipients whose email app uses dark mode (Apple Mail, iOS Mail) see adapted colors instead of your light design on a dark surface:

• Blocks using default colors switch to the standard dark palette.
• Custom colors that would be hard to read on a dark background are adjusted automatically: the hue stays yours, the brightness shifts until the text is legible.
• Sections with their own background color keep it in dark mode, along with the colors inside them, so designed banners and cards stay exactly as you built them.

To art-direct the dark version yourself, switch the canvas toggle to Dark mode. Color fields in the inspector then edit the dark variant: Auto shows the color Helios derived, and picking a color replaces it for dark mode only (the reset button returns it to Auto). Your light-mode colors are never affected.

The inspector also warns when a color combination is hard to read (below the 4.5 contrast recommendation), in either mode.

Previewing

• The canvas has a Light mode / Dark mode toggle that simulates how email clients render each scheme, and switches the inspector between light and dark color editing.
• Preview opens a full render in a modal.
• Send preview emails the template to an address you choose, with merge fields filled with sample values. Always send one before relying on a template: real email clients are the only truth.

Using the template

Saved templates appear:

• In the email blast composer’s Templates tab: click Use to apply it as the campaign’s starting point, then edit freely (Revert to a blank email undoes it).
• In the flow Send email action’s composer, the same way.
• On the Templates page for editing, duplicating, and previewing.

Applying a template copies the design into the campaign: later edits to the template don’t change past campaigns.