It can be in the UK, depending on how much the person's stammer affects their day-to-day life. There's a points-based system for the Benefits system and if the stammer severely impacts a person's life, they can claim state benefits. [Is Stammering A Disability? | STAMMA](https://stamma.org/about-stammering/stammering-disability) And in the UK, stammering is considered a disability from an employment standpoint with associated protections and requirements to accommodate the needs of employees who stammer.