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Email Structure

HTML Email

An email formatted with HTML code that allows rich visual design including images, colors, and formatted text.

Definition

An HTML email uses Hypertext Markup Language to create visually designed messages with formatting, images, links, colors, and layouts beyond what plain text allows. Unlike web pages, HTML emails require specialized coding techniques due to limited CSS support in email clients. Most marketing emails are HTML emails.

Why It Matters

HTML emails enable branded, visually engaging messages that can include images, buttons, and designed layouts. They look professional and can be much more compelling than plain text. However, they require careful coding to display correctly across different email clients.

How It Works

HTML emails use HTML markup and inline CSS styling to create designs. Due to email client limitations, they often use table-based layouts and inline styles rather than modern CSS. The HTML is sent along with a plain text alternative (multipart) for clients that do not render HTML.

Best Practices

  • 1Use table-based layouts for consistent rendering across clients
  • 2Inline all CSS styles rather than using stylesheets
  • 3Always include a plain text version of your email
  • 4Test across multiple email clients before sending

Frequently Asked Questions

Many email clients, especially Outlook, have limited CSS support and do not properly render div-based layouts. Tables provide the most reliable structure for layouts that work across all email clients.

Send HTML emails with a plain text alternative (multipart format). HTML enables branding and design, while plain text ensures readability everywhere. Some audiences prefer plain text; test both formats.