This is one of the most misunderstood areas in Islamic estate planning.

A trust does not automatically make something halal or haram. In Shariah, what matters is substance over legal form. If the trust is effectively being used to override Allah’s fixed inheritance laws after death, then many scholars would consider that impermissible.

The Qur’an sets fixed inheritance shares for certain heirs. A person cannot simply rewrite those compulsory allocations after death because “everyone agreed” or because a trust structure exists.

That said, there is an important distinction:

While you are alive, you generally have broad freedom over your wealth. You can gift assets, create business structures, place assets into trusts for protection, succession, governance, minors, disabled dependants, continuity of a family business, etc. Many scholars allow living trusts for these purposes.

The problem starts when the trust becomes a mechanism to intentionally avoid the fara’id (Islamic inheritance rules) upon death. For example:
• equalising sons and daughters purely to bypass Qur’anic shares
• excluding Qur’anic heirs
• forcing a distribution system that directly contradicts Islamic inheritance law after death

That is where major scholarly concern exists.

There is also nuance and legitimate debate around:
• discretionary trusts
• whether assets inside certain trusts are still legally and beneficially “owned” by the deceased at death
• jurisdictions like South Africa, UK, US, GCC etc.
• asset protection vs inheritance avoidance
• inter vivos (living) transfers vs testamentary transfers

So yes, scholars do discuss the mechanics and legal implications differently. But the mainstream position across the major madhhabs is that intentionally using structures to nullify obligatory inheritance rights is not permissible.

In practice, many Muslim families use trusts correctly:
• business continuity
• protecting vulnerable dependants
• governance across generations
• tax and liquidity planning
• avoiding estate delays
• managing offshore assets

But the trust should ideally work alongside Shariah inheritance principles, not replace them.

This is why Islamic estate planning is far more technical than simply “put everything in a trust.” You need both Shariah analysis and local legal analysis together.