The firm said that people are playing a type of “inheritance roulette”, with many saving less and others delaying house moves as they bank on a legacy windfall.
It surveyed 1,000 UK adults who own a property and have a pension.
The research found 15% of Brits aged between 16 and 54, or more than five million adults, have revised their financial plans.
The largest proportion of changes by under 55s were made to their saving plans, with people either saving less (25%) or saving more (25%) as a result of their inheritance expectations.
Neil Jones, wealth management and tax specialist at Canada Life, said: “It’s a risky strategy to bank on an inheritance that may not materialise and an even riskier strategy to change your plans based on what you expect to inherit.
“By essentially playing inheritance roulette, people are putting their financial health at risk.
“This is especially true when you consider that there are over half a million people aged 90+ in the UK, meaning that many people won’t receive an inheritance until retirement, or possibly not at all in the instance that care costs erode the value of any inheritance.
“On a positive note, those who decided to save more in light of their inheritance expectations appear to be taking a longer-term of their financial situation.
“Our research last year found that one in 25 people have inheritance expectations that amount to £1m ($1.26, €1.12m), with one in 50 people’s inheritance expectations exceeding £5m.”
The research also found that 22% of under 55s also plan to delay moving house until they receive their inheritance.
Half of those who opted to stay put were aged between 16 and 34.
However, fewer than one in six (14%) chose not to buy a house as a result of their inheritance expectations.
“While inheriting assets such as property or other wealth can be a significant boon to an individual’s wealth, changing financial plans based on such a promise is short-sighted,” Jones added.“That is why good conversations between benefactors and beneficiaries are so crucial.
“With the help of a financial adviser, these discussions can help heirs better prepare for their inheritance and ensure that inter-generational wealth planning makes the most of the opportunities available.”