You only risk having a future "shortfall" if you now decide to carry on with the endowment, rather than surrendering your endowment and switching to a repayment mortgage.

BBC: NEWS | Business | Ask the expert special: Endowments

Determine your current financial situation. (2) Figure out where you want to be at given times in the future. (3) Make reasonable assumptions about key factors like pay raises, savings, spending levels, inflation, insurance coverage, investment returns for different kinds of assets and the like. (4) Run the numbers over time. (5) Fiddle with the assumptions to cover any shortfall or, if financially set, to reduce risk.

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