What is a conditional will?

A conditional will can be an attested will, a holographic will or a nuncupative will. Any of these become a conditional will when the gifts in the will are conditioned on some event occurring or on whether some fact is true or not. For example, my will would be conditional if it said “if I die of cancer, this is my will and I want half of my estate to go to charities for research and the other half of my estate to go to my spouse.” This will would only be effective if I did, in fact, die of cancer. If I died by any other means, and did not have any other wills, intestacy would apply.