What is the Stammering Tax? The hidden costs of communication barriers
Nick Freear | 10 Sep 2026People who stammer often face barriers when interacting with businesses, public services and organisations. These barriers can occur face-to-face, over the phone, through automated systems and, increasingly, through AI-powered customer service tools.
While these moments may seem small in isolation, their cumulative impact can lead to financial costs, missed opportunities and emotional harm. It raises an important question: is there such a thing as a "Stammering Tax"?
This idea was sparked following a session at the STAMMAFEST conference in August about the barriers people who stammer encounter when accessing products and services. The charity STAMMA surveyed people who stammer about their experience of using the phone in 2025, and found that 32% reported having their words guessed or assumed, while 24% hit interactive voice recognition issues.
We've all had experiences over the years of the person on the other end of the call being impatient, talking over, mocking or even putting the phone down on the caller, who is stammering and struggling to get their words out. The organisations can be banks, insurance companies, GPs surgeries, 999 call handlers – anyone. And the problems and discrimination can extend from staff in shops, cafes and restaurants, to human call handlers, to automated phone systems, and increasingly to AI-driven systems.
In the workshop, STAMMA’s CEO, Jane Powell, implored attendees to contact STAMMA at the time when these events occur, and share the details, so that the charity can advocate on our behalf. While STAMMA knows that discrimination occurs, the challenge it faces is a lack of concrete evidence to approach organisations with. This is because the people affected don’t reach out in the moment.
The effects of these interactions face-to-face or on the phone for the person who stammers can be serious over time. Feelings of anger, frustration, distress, helplessness, and a lowering of self-esteem can build up, and stay with us – leaving long-lasting emotional and psychological harm. 
The result of these harms is that we are often reluctant to make phone calls, or interact with staff face-to-face. This has a knock-on effect – by avoiding these interactions we may miss out. For example, we have insurance that can't be arranged purely online and requires a phone call. When the insurance needs renewing, we are reluctant to make phone calls to other businesses and shop around for a better price. Or we are unwilling to complain in a restaurant when there is a problem with the food or service.
In the world of ADHD these extra costs, missed opportunities, or sanctions (for example, being fined because you forget to renew parking, or impulsively buying unnecessary things) have a label – the "ADHD Tax". They are a widely recognised financial burden and consequence of ADHD. In the case of ADHD, the reason is forgetfulness, struggling to prioritise and manage tasks, impulsiveness, and other ADHD traits. The underlying cause of some of these traits is executive dysfunction.
I'm going to borrow the phrase and carry it over to the world of stammering/stuttering – and call it "The Stammering Tax". Different underlying causes, but similar outcomes in extra financial and other costs.
The accessibility challenge organisations often overlook
When organisations think about accessibility, they often focus on websites, apps and documents. However, accessibility also extends to customer service interactions, call centres, chatbots, voice systems and AI assistants.
If a customer avoids contacting your organisation because they fear being interrupted, rushed or misunderstood, that is an accessibility barrier. And when that barrier results in someone paying more, missing a service or avoiding support altogether, the real-world consequences can be significant.
The idea of a "Stammering Tax" highlights an important reality: when services are not designed to accommodate different ways of communicating, the cost is often borne by the individual rather than the organisation.
Whether the barrier comes from a member of staff, an automated phone system or an AI-powered assistant, the outcome can be the same: exclusion, missed opportunities and additional costs.
Recognising these barriers is the first step. Designing accessible, inclusive services that work for everyone is the next.
AbilityNet works with organisations to create more inclusive customer experiences through accessibility audits, disabled user testing, consultancy and training. Organisations looking to improve customer service accessibility may also find our training on inclusive and accessible customer services helpful.
