Many of Gen X are relying on an inheritance to fund their own retirement

Billions of pounds worth of assets are expected to be passed to younger generations over the coming years, but countless parents are still leaving their children in the dark over their inheritance plans.

Some 36 per cent of Generation X, those aged 44 to 59, said they haven't discussed inheritance plans with their parents, according to figures from wealth manager Charles Stanley.

This is despite recent figures from Hargreaves Lansdown revealing that a third of people are relying on receiving an inheritance from family in order to be able to fund their own retirement.

Money is often seen as a taboo topic among family members, and this is especially the case when it comes to inheritance plans. Failing to discuss it, however, could leave millions of people unprepared to deal with any money they inherit, and the tax bills associated with this.

An increasing number of estates are becoming subject to inheritance tax as a result of frozen thresholds and inheritance tax calculation changes.

Recent figures from HM Revenue & Customs indicate that inheritance tax receipts are on track to reach £9billion by the end of the tax year. A record high of £3.1billion was collected by the taxman between April and July alone, an increase of £200million compared to a year ago.

> How inheritance tax works - and what families MUST know

Not talking about it: For millennials, almost nine out of ten, 89%, said they haven't discussed their parents' inheritance plans

Lisa Caplan, director of Charles Stanley Direct advice and guidance, said: 'With thresholds frozen until 2030, and pension assets being included in estates from 2027, the number of families finding themselves having to pay IHT on their loved ones' estates is set to grow sharply.

'It's critical that people understand the value of their estates, have plans in place for how they will pass wealth on, and, importantly, communicate this with their family.'

While Generation X, aged between 44 and 59, are first in line to inherit from older generations, many millennials are also likely to receive inheritances from parents of the baby boomer generation.

As many as 27 per cent of millennials said they don't know what their parents' inheritance plans are.

As a result, many will have no idea whether they are in line to inherit anything, and will not be able to take action to prepare for this, and to deal with any potential tax bills.

Meanwhile, a fifth of baby boomers have yet to draft a will, meaning that they risk their estate being distributed according tot the rules of intestacy, rather than their own wishes.

Caplan said: 'Passing on wealth and inheritance takes careful planning and consideration.

'Not only does it ensure that there won't be any unexpected or avoidable tax bills, but also that everyone involved knows what to expect.

'What's clear from our research is that not everyone is in the loop when it comes to inheritance planning.

'This leaves the door open to families finding themselves having to settle unnecessarily large or unexpected tax bills, or even jeopardising hopes to pass on wealth to their loved ones.'

> How to make a watertight will: 10 tips to getting your last wishes fulfilled

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Do YOU know your parents' inheritance plans?