Pension savers are being warned to regularly update the documents that say who should get money from their pension pot if they die.
This is because families are increasingly challenging decisions made by pension scheme trustees following the death of a member, the Daily Telegraph reports.
It falls to trustees of the scheme to make such decisions, but where the savers' intentions were not clear, disputes arise over who should be recognised as beneficiaries.
The issue primarily involves those belonging to company pension schemes where benefits are linked to their salaries.
With these, workers paying in should be asked to fill in an "expression of wish" form. This indicates who would receive the pension benefits if they were to die.
Trustees must take members' wishes into account, but do not have to follow them if they decide another solution is more appropriate or if, for instance, the scheme rules do not permit those wishes to be carried out.
In many cases, people fill in their expression of wish form when they first become a scheme member and never update it to reflect changes to their circumstances.
The Association of Member Nominated Trustees said there had been a recent rise in disputes over payments.
Barry Parr, the co-chairman of the organisation, said it was increasingly difficult for trustees to make decisions, particularly in cases where complex family arrangements were in place.
Parr stressed the importance of having a will in addition to an up-to-date expression of wish form. He said: "Trustees do take into account a member's wishes, but they have a duty to consider other potential beneficiaries, especially if the paperwork seems outdated.
"Common complexities arise when pension savers remarry and fail to update their wishes - especially where children are involved in one or both of the relationships.
"It is important that members keep their wishes updated and have a current will to reduce the likelihood that decisions will be open to challenge."
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