Colour does its work before anyone reads a single word. It's the first thing a subscriber processes when an email opens, and it quietly shapes where their eye goes next, what feels important, and what feels safe to click. Most of that happens below conscious awareness, which is exactly why it's worth being deliberate about.

Contrast matters more than the specific colour

There's a persistent myth that certain colours convert better than others, red for urgency, green for go, and so on. In practice, contrast against the surrounding design consistently matters more than which specific colour you pick. A CTA button in your brand's accent colour will outperform a button that blends into the background, regardless of whether that accent colour is orange, teal, or anything else. The job of a CTA colour is to be the one thing on the page that unmistakably says click here.

Colour as hierarchy, not decoration

Every colour choice in an email is doing a hierarchy job, whether you intend it to or not. If your headline, body copy, and CTA are all rendered with similar visual weight, the reader has to work to figure out what matters. Using colour deliberately, a stronger tone for the one action you want taken, a quieter palette for supporting content, does that work for them.

TIP

If you only have one accent colour to spend, spend it on the CTA button. Everything else in the email can live in your neutral brand palette and still perform well.

Consistency builds recognition over time

A subscriber who's seen ten emails from you has built an unconscious association with your colour palette, the same way they recognise a brand's logo at a glance. Changing your colour scheme frequently resets that recognition every time. Consistency compounds: the tenth email from a sender with a stable visual identity gets processed faster, and often trusted more, than the tenth email from a sender who looks different each time.

Accessibility is not optional

Low-contrast text, light grey on white, pale colour on pale background, isn't just a stylistic risk. It genuinely excludes subscribers with low vision or colour vision deficiencies, and it degrades readability for everyone in poor lighting or on a low-quality screen. A simple check: if you're unsure whether a colour combination has enough contrast, it probably doesn't. Body text should sit close to a dark neutral against a light background, reserving your brighter brand colours for accents, buttons, and highlights rather than for large blocks of text.

Dark mode changes the equation

A growing share of subscribers read email with dark mode enabled, which can invert or reinterpret your colours in ways you didn't design for. A logo with a transparent background and dark text can become invisible against a dark mode background. Testing your design in both light and dark rendering before a major send catches this kind of failure before it reaches a subscriber's inbox rather than after.

Applying this without overthinking it

You don't need a colour theory degree to get this right. Pick one accent colour for action, keep your body copy high-contrast and readable, stay consistent send over send, and check how the email renders in dark mode before you send it. That's most of the leverage available here, and it costs a few extra minutes of review, not a redesign.

Mail Blaze is an email marketing platform built for teams who want more from email. The drag-and-drop builder makes it straightforward to keep your brand colours consistent across every send without starting from scratch each time.

Frequently Asked Questions

Does the colour of my CTA button really matter?

Contrast against the surrounding design matters more than the specific colour. A button in your brand's accent colour that stands out clearly will outperform one that blends into the page.

Should I test different colours for different types of email?

Consistency in your core palette builds recognition over time, which matters more for most senders than optimising colour per campaign. Reserve testing for genuinely uncertain decisions, like a new CTA colour.

How do I make sure my email looks right in dark mode?

Test rendering in both light and dark mode before a major send. Pay particular attention to logos with transparent backgrounds and any dark text that could disappear against a dark background.

What's a simple accessibility check for email colour?

If you're unsure whether text has enough contrast against its background, it probably doesn't. Keep body copy close to a dark neutral on a light background and reserve bright brand colours for accents.