A Discretionary Trust of Residue including RNRB (Residential Nil Rate Band) is a trust established in a person's will to hold the residue of their estate, after all debts and other specific legacies have been paid. This type of trust can be used to provide greater flexibility and control over the distribution of assets to beneficiaries, especially in cases where the estate is large or complex.

The inclusion of RNRB in the Discretionary Trust of Residue allows the trustees to claim this additional inheritance tax relief on the value of a property that has been left to a direct descendant of the deceased, such as a child or grandchild. RNRB was introduced in April 2017 to provide an additional tax-free allowance for estates that include a residential property.

By establishing a Discretionary Trust of Residue including RNRB, the testator (the person making the will) can ensure that their assets are distributed according to their wishes and in the most tax-efficient manner. The trustees of the trust have the discretion to distribute the assets to the beneficiaries at any time, taking into account their individual needs and circumstances. This can be particularly useful if some beneficiaries are too young or not capable of managing their inheritance.