In brief: you should write a Will to make sure the right people get whatever you leave behind. Don't write a Will and the wrong people might get it, which sometimes means the state. So we suggest writing a Will.
More details below..
Unless you make a Will, you cannot guarantee that your belongings will be distributed as you want when you die. It is surprising the number of individuals who do not have a Will and who die without making sure that those whom they wish to benefit from their estate after their death do so. As a result, many unnecessary complications arise, adding to the grief of the bereaved and the expense of winding up the deceased person's estate.
If you die without a Will (“intestate“) the law decides who will receive your possessions. If you are married and die intestate, it is a common misconception that the surviving spouse inherits everything. This is not always the case and depends on the size of the estate; brothers and sisters and parents may make a claim. If you are not married but living with your partner and die intestate, your partner receives nothing.
Only a legally adopted child is classed (in law) as a son or daughter. Stepchildren need to be protected and named in the Will of their step-parent, if that step-parent wishes them to inherit as their natural child would.
Anyone over the age of 18 (12 in Scotland) can make a Will. Apart from the wish to choose to whom you leave your estate, you should also consider the following reasons for writing a Will:
Next: Executors.
See Legal Wills - a range of standard Wills for use in England, Wales and Scotland.