Are DIY and AI Wills Legal? The Risks of Writing Your Own Will

It is completely understandable why DIY Will kits, online Will templates, £10 supermarket Will kits and the use of AI to draft Wills are all so tempting. On the surface, writing a homemade Will seems like a convenient way to tick an important chore off your to-do list whilst saving you money. Doing so however raises an important question for many people looking into this process: are homemade Wills legal?

In short, the answer is yes. In England and Wales, if a Will meets basic requirements, you could technically write it yourself. Similarly, people often ask the question on whether online Wills are valid, which they certainly can be, provided they are executed correctly.

However, there is a big difference between a document being legally valid and a document actually doing what you want it to do. Unlike a bad DIY paint job, you will not be around to fix a mistake when it goes wrong.

Here are some hidden risks of taking the DIY route and why something that can seem cheap and convenient now, could cost your loved ones thousands of pounds later.

Whilst a homemade Will could be perfectly drafted, if it is not signed and witnessed correctly, the whole document will be rendered void. The law is incredibly strict and unforgiving about this. One minor slip up, such as having the wrong person in the room at the wrong second, can have catastrophic results and could accidentally disqualify your loved ones from inheriting anything at all, or invalidate the entire Will without you ever knowing.

When you write and execute a Will yourself, there is nobody there to ensure that this crucial step is done correctly. Without a professional overseeing this final step, you are essentially gambling that you executed the Will with absolute legal certainty.

It is a common belief that once you have written a Will, you assume that your estate is protected forever. However, English law contains various hidden ‘triggers’ that can accidentally cancel, alter or completely change your Will without your knowledge.

Major life milestones could completely rewrite your legacy. For example, if you create a homemade Will whilst living with your partner and then later choose to marry or enter into a civil partnership, that act alone can completely void the document overnight. Basic DIY Will kits and standard templates are static. They cannot analyse future plans or give you a warning about specific clauses required to protect a document against automatic revocation.

If you fall into this trap, you could spend the rest of your life thinking that your loved ones are protected, when in fact your estate would default entirely to the government’s strict rules of intestacy.

If you were to sit down and write a Will yourself, more often than not you would be using everyday language to express your wishes. This is where the question are online wills valid becomes almost a secondary issue to a bigger problem: is the wording included actually enforceable?

When people use DIY kits or AI generated Wills, they usually focus on their major assets such as their property or bank accounts, however there is a risk of a failure to account for everything you own, leading to a legal nightmare: partial intestacy. If a homemade Will fails to distribute all of your assets, they are left completely unprotected and when this happens, the Will only will cover part of your estate. The wealth you have left over is treated as though you have died without a Will and it is handed over to the government’s rules of intestacy. Standard forms and online software will not fully audit your finances or ensure that 100% of your estate is legally captured.

For those who have young children, a Will is the only legal document that you can officially name who raises them should something happen to you. Unfortunately, this is frequently one of the most flawed areas in a homemade Will. Many DIY kits fail to mention guardianship completely and even when they do, poor structure and everyday language can easily render the appointment of a guardian invalid. The criteria to legally appoint a guardian is extremely specific and if you make a mistake it could be completely rejected.

One of the biggest mistakes in a homemade Will is assuming that your estate is too simple to worry about tax. Basic DIY forms or AI generated Wills often completely overlook Inheritance Tax (IHT), which could easily trigger a 40% tax bill on your wealth. IHT rules are complex, especially when calculating property values, allowances and any investments that you might have. A static template will not be able to flag tax-saving opportunities that would protect your estate. By the time your loved ones realise that a legal professional could have shielded your wealth from the taxman, it is already too late.

A lot of people use a homemade Will to protect young children, vulnerable relatives or blended families and doing this requires a legal structure known as a Trust, which is where homemade Wills fall short on. Generic forms or AI could completely misadvise a wrong type of trust for your family dynamic. Even worse, they could fail to grant your Trustees the correct legal powers to manage the assets properly. The consequences are severe, you could accidentally disinherit your own children in a blended family, give an 18-year old a big sum of money before they are mature enough to spend it, or accidentally strip a vulnerable relative of their government benefits.

If you own a holiday home or any other assets overseas, a homemade Will is a major risk. Many people believe that a UK document will cover overseas assets, however foreign assets require highly specialist care. Every country has their own strict inheritance laws and a basic Will kit or AI may fail to address complex cross-border tax issues. Failing to properly structure your Will around foreign assets could leave your loved ones facing a nightmare of competing legal systems and unexpected foreign tax bills.

If you own a business, a share in a partnership or agricultural land, doing a Will yourself will be completely inadequate. Commercial and farming assets will raise distinct legal and tax issues that DIY kits will not be able to handle. Without a legal professional, a homemade Will can disrupt your business continuity and can completely overlook tax reliefs. Failing to structure your Will correctly could force your family to sell the business or agricultural land just to pay the taxman. It takes an expert planning to keep a business running and in the right hands.

In a paperless world, there is an increase of online investments, digital currency and digital photo archives. These are most frequently the most forgotten assets in a homemade Will. Under UK law, these are recognised as personal property and yet a DIY Will would not necessarily take them into account. Most crucially, if you own crypto-assets, relying on a standard template risks your private keys which could lead them to being lost forever, leaving your digital assets locked away in a virtual vault.

A major downfall of DIY Wills and AI written Wills is that no one is vetting the person making the Will and the signing process. Without an independent professional involved, these Wills would be vulnerable to being challenged by the court if you pass away. Disgruntled relatives could easily claim that you lacked the mental capacity to understand what you were doing and what you were signing, or that you were pressured into making the Will. Because there is no independent capacity check by a third party to prove otherwise, these accusations are difficult for your executors to fight. A successful challenge could render your entire Will invalid.

The risks outlined above are serious, but they are entirely avoidable. Working with a solicitor who specialises in wills and estate planning means your wishes are properly drafted, legally sound, and will stand the test of time.

A professional Will from Franklins is tailored to your family, assets and circumstances. We integrate inheritance tax mitigation, reliefs and allowances with lifetime planning and pension nominations. We supervise the signing process to ensure absolute legal certainty, and we keep detailed file notes on your instructions and capacity which protect your estate if any challenge ever arises.

For many families, modest upfront legal costs prevent far greater expense, delay and distress later. Whether you’re in Northampton, Milton Keynes, or surrounding areas, our experienced team can guide you through the process with clarity and confidence.

Disclaimer: This article provides general information only and does not constitute legal advice. You should obtain advice tailored to your circumstances from a qualified solicitor before taking or refraining from any action.