According to a report published by the Office for National Statistics (ONS) in 2019, Cardiff had approximately 19,500 individuals classified as "high-net-worth individuals (HNWIs)." These are people with investable assets of over £1 million (excluding main residences and pensions).
However, it's important to note that this data is a few years old, and the number of wealthy individuals in Cardiff may have changed since then. Additionally, the definition of "rich" can be subjective and may vary depending on individual perspectives and criteria.
For a more up-to-date estimate, you can refer to the most recent wealth distribution statistics published by reputable sources such as the ONS or independent research firms that specialize in wealth analysis.