If you are leaving everything to your spouse there is no immediate tax to pay because gifts between spouses are tax free.

ISAs and PEPs lose their tax-free status once you die and are included in your estate.

You only have to worry about paying IHT on a gift if the legacy is paid before tax. Often, the estate pays the tax. If there is not enough money to cover the tax once legacies have been paid, you may end up with a bill.

[sub] Potentially exempt transfers (PETs)

A PET is tax free is you survive for at least seven years after making the gift. It is taxable on a reducing scale if you die after three years. After your death tax is payable on PETs made in the previous seven years if it means the estate comes to more than the IHT threshold.

IHT planning is complex and you need to seek professional advice.