People in Southampton are the most likely to contest a will if they feel a loved one’s assets have not been divided fairly, according to recent research carried out by a leading insurance company.

Some 31 per cent of residents of the Hampshire City said they would be prepared to take this course of action, closely followed by citizens of London and Norwich (29 per cent each).

The survey, carried out by Direct Line Insurance, sampled 2,000 nationally representative adults. It also spoke to 100 family lawyers to ascertain the most common legal reasons why wills are challenged.

Top of the list was “undue influence”, followed by “lack of knowledge and approval” and “fraudulent or forged wills”.

Despite the reason’s popularity, lawyers warned of the potential issues related to challenging a will on the grounds of “undue influence”, pointing out that the burden of proof is high and falls on the person challenging.

The number of disputed wills saw a slight increase in 2018 with possible contributory factors including the rise in second families, people’s greater understanding of legal processes, and some law firms’ willingness to take cases on a no-win, no-fee basis.

However, the overall number of disputed cases remains small and needs to be kept in perspective, suggests Neil Fraser, partner at Fraser and Fraser.

“There’s a widespread belief that, because people are living longer and dementia rates are rising, people may be making wills when they are not be in the best of health. Therefore, the wills are more susceptible to challenges.

“However, the truth remains that very few probate cases are ever challenged in the Chancery Division of the High Court, which handles all contested cases. In the past decade less than 0.1 per cent end up in court and, if anything, the trend suggests a decline rather than an increase.

“This goes to prove that, as the burden of proof is on the challenger, it can be a very risky option.”

Figures from the Chancery Division of the High Court state that in 2018 there were 86 contested probate cases out of a total of 264,486, compared to 80 out of 259,956 in 2017. The highest number of disputes in the past decade was 178 out of 247,298 in 2014.

Estimates suggest around 29 million people in the UK have not written a will at all, either formally or informally.