Lasting Power of Attorney vs a Will: What's the Difference and Do You Need Both?

Many people who finally get around to writing a will feel they have ticked the box on estate planning. They have not — at least not completely. A will is essential, but it only takes effect on death. A lasting power of attorney (LPA) covers something equally important: what happens if you lose the ability to make decisions for yourself while you are still alive.

What Is a Lasting Power of Attorney?

A lasting power of attorney is a legal document that authorises someone you trust — called your attorney — to make decisions on your behalf if you lose mental capacity. In England and Wales, there are two types:

• Property and Financial Affairs LPA — allows your attorney to manage your bank accounts, pay bills, sell property, and handle financial matters on your behalf
• Health and Welfare LPA — allows your attorney to make decisions about your medical treatment, care arrangements, and day-to-day welfare, including decisions about life-sustaining treatment if you specify this

Both must be registered with the Office of the Public Guardian before they can be used. The registration process currently takes up to 20 weeks, which is why acting early — while you have capacity and are not in immediate need — is strongly advisable.

What Is the Critical Difference Between an LPA and a Will?

The single most important distinction: an LPA operates during your lifetime, if and when you lose capacity. A will operates only after your death, and is automatically revoked by a registered LPA where financial matters overlap.

This means neither document replaces the other. Your will cannot instruct anyone to act on your behalf while you are alive — it has no force until you die. Your LPA cannot direct the distribution of your estate after death — it ends at the moment of death. You need both to be fully protected at every stage.

What Happens Without an LPA?

If you lose mental capacity without a registered LPA in place, no one — not your spouse, not your children, not your closest family members — has automatic authority to manage your financial affairs or make decisions about your care. To gain that authority, they must apply to the Court of Protection to be appointed as your deputy.

This process is slow, expensive (typically £1,000–£3,000 in legal and court fees), and ongoing — a deputy must report to the court annually. It is significantly more burdensome than having a registered LPA, and the court may not appoint the person your family assumed would take on the role.

Who Should Have an LPA?

The honest answer is: everyone with assets, a mortgage, or people who depend on them. Loss of mental capacity is not exclusively an issue for the elderly — illness, accident, or injury can affect anyone at any age. An LPA registered in your 40s or 50s is far easier to arrange than one needed urgently in a crisis.

For business owners, an LPA for property and financial affairs is particularly important — without one, a company where you are a sole director or key signatory may be unable to function if you become incapacitated.

Writing a Will Alongside Your LPA

Getting an LPA and a will in place at the same time is the most practical approach to comprehensive estate planning. Both documents require you to have mental capacity when they are created — capacity you cannot guarantee in the future. Arranging both while you are well and able ensures neither is ever needed urgently and unavailable.

For LPA registration, the GOV.UK LPA service allows you to apply online directly with the Office of the Public Guardian. For a will, Wills Assured produces a fully compliant, legally binding document from £19.99 — so the two together represent a complete foundation for protecting yourself and your family at every stage.