A pilot trust set up by a settlor in his lifetime to benefit a surviving spouse after his death. It is usually set up to receive death benefits from a pension scheme or life assurance policy death benefits on the settlor's death. It is also, typically, drafted as a discretionary trust with the surviving spouse as one of the beneficiaries.

The aim of the spousal bypass trust is to prevent death benefits falling into the settlor's or the surviving spouse's estate on death where they could be potentially subject to inheritance tax (IHT).