Complete guide to making a Will and what it should include

A Will allows you to dispose of all assets owned personally on the date of your death, and helps avoid the often unfortunate consequences of intestacy. Some Wills are deliberately drafted to dispose of limited assets – e.g. "all my assets in the UK but not my property in Spain". A Will has no effect prior to death and can be changed at any time as long as you are mentally capable. A new Will normally revokes an earlier one. Marriage or civil partnership automatically revokes a Will, but divorce only revokes clauses which benefited your former spouse or partner.

Under English law nobody is obliged to leave anything to anyone. But, the law does give people who were financially dependant on you a right to claim from your estate if you have not provided adequately for them. This includes a surviving spouse, civil partner, minor children, and possibly unmarried partners, or others who were financially dependant.

Dying without a Will, or "intestate" can be unfortunate, particularly if you leave a surviving spouse / civil partner and children. The rules give a "statutory legacy" to the surviving spouse/civil partner of £250,000 (and all chattels) and half of the remainder of whatever is left after that legacy. The other half goes in trust for the children at 18, which can give rise to an unwelcome inheritance tax liability.

A UK Will disposes of cash, houses/land, investments, insurance policies, chattels (house contents, cars, boats, animals, jewellery) and anything else you own anywhere in the world. It is usual to make separate Wills in non-UK countries where land is owned, to simplify probate and make it easier to comply with the "forced heirship" rules found in many countries which can override a UK Will.

A Will does not normally dispose of jointly owned property, whether a house, bank account or investments. These pass by "survivorship" after the first death, on production of a death certificate. Even though you may own property jointly, it does not mean it will automatically pass to the joint owner – it depends how the ownership is structured. Pension benefits may often pass under a separate Trust Deed. Family trusts under which you benefited, pass under the terms of the pre-existing Trust Deed or Will, and not your Will. Life policies written in trust are an example of assets passing on death, but not by your Will.

IHT is a form of "wealth tax" on assets transferred during lifetime or on death by Will or intestacy. A Will can play an important part in avoiding IHT, as well as controlling your assets by creating Trusts for family members. The “transferable nil rate band” introduced in 2007 allows married couples or civil partners to avoid IHT on assets up to £650,000 plus a further allowance is available in respect of property passing to direct descendants; this will be worth up to £350,000 for married couples leaving property to children or grandchildren by tax year 2020/2021. Over that level complex planning is needed to mitigate IHT, and to take maximum advantage of the reliefs for agricultural or business assets.

Couples of different domicile need to take care as the exemption for assets passing from a UK spouse to a non-UK spouse is limited to £325,000. A non-UK individual living in the UK can shelter assets kept outside the UK from IHT for up to 15 years, after which their domicile is deemed to be UK, and their worldwide assets become liable to IHT.

After someone dies their "personal representatives" ("PRs") have legal responsibility for their assets and liabilities. PRs may be "executors" named in a Will or "administrators" if there is no Will. The PR's job is to collect the assets, pay off debts and IHT, and give effect to the Will or intestacy rules. If there are ongoing Trusts under the Will – e.g. if beneficiaries are under 18 - the PRs are often appointed as Trustees too, but it can be different people. It is vital to select suitable PRs and Trustees. Spouses or civil partners may appoint each other, and perhaps one or more children if mature enough. However, appointing children can give rise to conflicts, e.g. if there is a trust of which a step-parent and children are beneficiaries. Some parents will be wary of appointing children who may face divorce or be deemed "unsuitable" to control substantial assets. Parents (if not too old), siblings, or close family friends are other options. Failing them, a solicitor or accountant is a common choice. Banks are an alternative. As a precaution, if appointing an elderly executor, is to nominate a substitute in case they are unwilling or unable to act.

Many people fail to express their wishes but it is best to choose between burial or cremation. Then, family members are not left to make an awkward decision at a stressful time. If you want to donate organs for medical research or transplants, that should also be made clear.

If both parents die, children under 18 need legal guardians to take key decisions – such as where they should live, and go to school. It is usual to name them in your Will. The people you appoint will usually be those with whom the children will live. Others may hold the purse-strings as Trustees, and manage the children's inheritance until they come of age.

There are many aspects to consider before writing a Will. Circumstances differ and so individual bespoke advice is necessary. However, particular care is needed in the case of:

• unmarried couples owning a property;
• couples of different domicile;
• people owning property abroad;
• any married couple with combined assets over £650,000;
• any unmarried couple or single person with assets over £325,000;
• anyone with pension or insurance;
• funds outside their estates;
• anyone who has been divorced without achieving a “clean break”.

By taking specialist advice, unnecessary IHT liabilities may be avoided, not to mention litigation after your death whether from former spouses, or partners who were financially dependant on you.