Octopus Energy: Monthly energy email update | Trials

The challenge: people struggle to understand the cost of credit.

In 2024 we partnered with ClearScore to explore whether clearer, more intuitive credit information could improve consumer comprehension. We were interested in whether including APR and a representative example helps when people are deciding between loans that last less than a year.

The research: testing how to present credit costs more effectively

Working with our research partner – Thinks Insights – we ran a randomised controlled trial with over 2,000 participants, testing three different ways of presenting the cost of credit:

The Control Version (current standard) – The original ClearScore interface, featuring APR and a representative example.
A Pure Plain Numbers Version – A version that simplified applied the Plain Numbers Method, including removing APR and the representative example.
A Plain Numbers Version within current regulations – A redesigned version applying the Plain Numbers Method while keeping APR and the representative example.

Visual shows: The three ways to communicate the cost of credit – in each arm participants saw a different interface

The results: Plain Numbers Method significantly improves understanding.

The findings were striking:

The Plain Numbers version doubled comprehension within existing regulations – when APR and the representative example were included.
The ‘pure’ Plain Numbers version almost tripled comprehension when APR and the representative example were removed.
Perceived clarity was high across all versions, but actual comprehension lagged far behind. This highlights a major gap—people think they understand, but in reality, they don’t.

Read the deep dive on the Clearscore APR trial

“Understanding important documents, like bills and safety advice, should not be a test. They should be simple and accessible to everyone, regardless of comprehension level. We already offer our documentation in alternative formats and languages to cater to our customers’ needs, so trialling the Plain Numbers Method was a natural next step in making our communications even more accessible.”

— Phil Burrows, Head of Customer Vulnerability at Cadent

Back to proof it works

Research: Initial trials report

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The challenge: people struggle to understand the cost of credit.

The research: testing how to present credit costs more effectively

The results: Plain Numbers Method significantly improves understanding.

Numbers shape what people understand, how they make decisions, and who they trust