What is the one-third rule in Islamic wills?

The one-third rule (Wasiyyah) allows you to leave up to one-third of your estate to anyone you choose, separate from the fixed inheritance shares. This is the optional bequest portion of Islamic inheritance.

The rule states:

• Up to 1/3 of your estate can be given freely to anyone (non-relatives, charities, causes)
• The remaining 2/3 (or more) must be distributed according to fixed shares
• You cannot use this one-third to give extra to fixed heirs without other heirs' consent

Common uses of the one-third:

• Charitable donations (Sadaqah Jariyah - ongoing charity)
• Gifts to friends or distant relatives
• Non-Muslim spouses (who don't inherit through fixed shares)
• Adopted children (who aren't automatic heirs)
• Supporting Islamic causes or institutions

You don't have to use the full one-third - you can use less or none at all. Any amount you don't use goes to your fixed share heirs.

This provision comes from hadith where the Prophet (peace be upon him) advised limiting optional bequests to one-third to protect the rights of heirs.