It would be so helpful if there was one theory of colour which removed subjectivity and differing opinions. Unfortunately, there isn’t, but there are some fascinating (and useful) theories and principles which can help guide decision-making.

When Monzo launched, every bank card in Britain was some shade of “trustworthy.” Navy, grey, the odd apologetic gold. Monzo went hot coral. Impossible to ignore, the colour rapidly became a recognisable Monzo code. Every time the card appeared across a bar or shop counter, it reinforced the connection between colour and brand.

Yet colour is often chosen far less deliberately, whether it be a flip through a Pantone book or a founder’s instinct. This on its own isn’t wrong. But the next steps of testing with your core audience and building context are what will make or break that choice. 

Brands are embedded in memory through repeated codes: colours, shapes, sounds and other cues that become attached to a set of associations. At first, a colour may simply attract attention. Over time, repeated exposure links it to everything people have seen, heard and experienced regarding the brand. Eventually, the colour alone can prime those associations – even before someone has consciously identified the brand.

Colour is a stimulus before it’s a preference

The eye registers colour in around 13 milliseconds. That’s before shape, before message, before the brain has decided what it’s looking at. Colour is registered quickly, then interpreted through memories and associations. 

London’s “official, iconic” red, as named by The London Museum, has been repeated across buses, signs, the Underground roundel and the London brand identity. What was once a transport colour is now a code for London through constant exposure and, over time, an inextricable connection to the city itself. 

But while colour is registered quickly, context is key to how we interpret it. Color-in-Context theory, from Karen Schloss and colleagues’ work on colour-emotion association, argues against the old assumption that red means danger or blue means trust in some fixed way. She says meaning is assembled in the moment, from the object, the category, and the cues around it. Red on a sports car reads as “speed”; on a hazard sign, “stop”. Same colour, different instructions. 

A 2025 Journal of Consumer Research study found consumers consistently rate muted colourways as more premium, because desaturation reads as the visual signature of age and heritage. We as consumers read the whole scene, not the colour alone. But inconveniently, none of this holds still across a population. Preference splits by culture, gender, and age. A colour system built for one market should not be a given where it hasn’t yet been tested.

How to apply the theory

• Start with a literature and competitor review: what’s already been tried in the category, and where the gap is.
• A/B test properly: not just colour against colour, but saturation and lightness against each other, shown to your different audience segments.
• Where the stakes justify it, test on people directly: eye-tracking and heatmaps for attention, biometric response for what happens before anyone can articulate a reaction, demographic surveys for the cultural and generational splits one opinion in a room will always miss.

This is an opportunity to give colour a defined role, then test whether it performs it. Does it attract attention, distinguish the brand and strengthen the associations you want people to remember? Taste still matters, but it’s not the end of the story.

Further reading

Elliot, A. J. & Maier, M. A., Colour-in-Context Theory (Advances in Experimental Social Psychology); Brogaard, B. & Gatzia, D. E. (2017), Cortical Color and the Cognitive Sciences; Labrecque, L. I. & Milne, G. R. (2012), Exciting Red and Competent Blue; Singh, S. (2006), Impact of Colour on Marketing; Hallock, J., colour preference survey data.