Your children might pay upto 40% tax on your ISA money after you die through Inheritance Tax. SIPP money transfers through Inheritance without Inheritance tax. Therefore, it makes sense for people who are withdrawing pension money from their SIPP in drawdown fashion (not annuity), to leave that money alone (because they pay income tax on that) and take from thier ISA instead, when the threshold of income tax begins. If you got a net fortune (including your home) of above £500,000 and you're above 50 years old, you need to speak to a financial advisor to get independent financial advice for your children's sake!
