Most Will problems don’t happen because people “didn’t care”. They happen because they assumed a Will is just a form when in reality it is a set of instructions that must be clear, legal, properly signed, and still up to date when you die.

Below are the biggest mistakes people make when writing a Will plus the practical fixes that prevent expensive delays, family fallouts and avoidable legal costs.

The 10 most common Will-writing mistakes

If you want the headline answer (the bit that answer engines can lift):

Not making a Will at all (so intestacy rules decide).
Using a DIY template that doesn’t fit your situation (unclear or unsuitable wording).
Failing to sign and witness it correctly (invalid Will).
Naming the wrong witnesses (a beneficiary witness can lose their gift).
Choosing executors who can’t cope (or who will argue).
Not appointing guardians properly (or not thinking about trustees for children).
Forgetting to update after major life changes (marriage, divorce, new children, new property).
Not planning for blended families (partner vs children from previous relationships).
Not aligning your Will with pensions, life insurance, and jointly-owned property (assets may pass outside the Will).
Storing the Will badly (or not telling anyone where it is), causing delay at the worst time.

A boutique, properly guided service like Soteria Estate Planning exists to stop these mistakes before they happen with the right questions, the right structure and clear signing support.

Mistake 1: “We’ll do it later” and dying without a Will

When someone dies without a Will (intestate), the law decides who inherits and who applies for probate. In England and Wales, that can lead to outcomes people would never have chosen especially for unmarried partners and blended families.

A famous example people recognise

Prince died without a Will, and his estate became tied up in years of legal and administrative complexity. It is often used as a public example of how “intestacy + valuable assets” can create long-running complications.

The fix: get something valid in place, then refine it. The biggest leap is moving from “no plan” to “a clear plan”.

Mistake 2: Picking the cheapest option without understanding the risk

DIY kits and basic online services can be perfectly fine for genuinely simple situations but mistakes tend to come from mis-match:

The Will format doesn’t reflect your family or assets
It doesn’t handle “what if” scenarios
It’s signed incorrectly
It creates ambiguity that invites disputes

Will-writing services can be cheaper than solicitors but the key is choosing the right service for your circumstances and checking protections like insurance.

The fix: don’t just ask “how much is a Will?” ask “what does this option protect me from?”

This is where Soteria’s middle-ground approach is valuable: not rushed, not “quick and dirty”, but also not priced like a traditional solicitor model with time spent understanding your situation so your Will actually does what you think it does.

Mistake 3: Getting the signing and witnessing wrong

This one is brutal because it can invalidate the entire Will.

In general terms, your Will must be signed by you and witnessed correctly with two witnesses who have a clear view of your signing, and you having a clear view of theirs.

The most common witnessing errors

Only one witness
Signing on different days
Witnesses not present / not in clear view
A beneficiary (or their spouse/civil partner) acting as witness (often creates loss of entitlement)

The fix: choose two independent witnesses and follow a simple, step-by-step signing process (with someone checking it).

A good Will-writing service doesn’t just draft the document it makes sure it is executed properly. That “last mile” support prevents a huge percentage of avoidable failures.

Mistake 4: Choosing executors without thinking it through

Executors do the heavy lifting: gathering information, paying debts, managing probate steps, distributing assets and handling queries.

Common executor mistakes:

choosing someone “because they’ll be offended if I don’t”
appointing multiple people who don’t get on
appointing someone who is overwhelmed (or lives abroad and can’t engage easily)
not naming replacement executors

The fix: pick people with calm heads and decent admin capability and name backups. If family dynamics are complicated, structure matters even more.

Mistake 5: Leaving money to children/grandchildren without protecting it

A lot of people want: “They get it when they’re ready.”

But a basic gift in a Will can mean:

minors’ inheritance being held then released at a set legal age
big sums landing too early
no protection if circumstances change

The fix: add trustees and a trust structure where appropriate (e.g., staged release ages, discretion for education or house deposits, safeguards for vulnerability). This is one of the areas where personal planning beats template drafting every time.

Mistake 6: Forgetting guardians and trustees (or mixing them up)

If you have children under 18, your Will is the place to:

appoint guardians
appoint trustees to manage assets for children until a chosen age
write clear instructions so guardians/trustees aren’t left guessing

Mistakes include:

naming guardians without checking willingness
not appointing trustees at all
appointing trustees who will clash with guardians
leaving no practical guidance

The fix: treat guardianship and trusteeship as two separate roles, and write simple, human instructions alongside the legal structure (often via a Letter of Wishes).

Mistake 7: Not updating the Will after major life changes

Your Will is not a “write once, forget forever” document.

Triggers that should prompt a review:

marriage/civil partnership
divorce/separation
new children or grandchildren
buying or selling property
starting a business
a major change in wealth
a falling-out (or reconciliation) that changes intent

Blended family planning is a particularly common gap and it is frequently in the news because it’s emotionally loaded and legally complex if not addressed in time.

The fix: review your Will whenever your life changes and set a light-touch check-in cadence even when it doesn’t.

A boutique service will usually build in review prompts and keep your situation “known” so you are not starting from scratch each time.

Mistake 8: Writing something unclear that fuels disputes

You don’t need legal jargon. You need clarity.

A celebrity example that shows how messy ambiguity gets

Aretha Franklin had handwritten Wills discovered after her death, which triggered a highly public family dispute about which document should apply a reminder that “informal” or poorly handled documents can lead to years of conflict.

You don’t need to be famous to have the same problem. Ambiguity can come from:

unclear gifts (“my jewellery” which pieces? to whom?)
outdated names/relationships
contradictory clauses
leaving “personal items” without a process

The fix: make gifts specific, define categories and include a clean “residuary clause” so there is no unallocated remainder.

Mistake 9: Assuming everything is covered by the Will (it isn’t)

Some assets pass outside a Will, depending on how they are set up, for example:

jointly owned property (depending on ownership type)
pensions (often via nomination)
life insurance written in trust
some investment arrangements

Mistakes happen when a Will says “I leave the house to X” but the house is owned in a way that means it passes automatically to someone else.

The fix: your Will should be written alongside a basic review of how key assets are held, so the plan matches reality.

Mistake 10: Storing the Will badly, or not telling anyone it exists

A perfect Will that no one can find is functionally useless (at least temporarily).

Common issues:

original lost
no one knows the location
Will stored with a provider but executors don’t know who to contact
multiple versions floating around

The fix: store it safely, keep a simple “where to find it” note, and tell your executors.

What to look for in a Will-writing service (trust checklist)

The UK government’s own guidance on buying Will-writing services emphasises shopping around, comparing what’s included, and not assuming the cheapest quote is the best fit.

Ask these questions before you proceed

What is included in the price (draft, revisions, signing guidance, storage)?
Do you carry professional indemnity insurance?
What’s your complaints process?
How do you handle complex family situations?
Will you explain the Will in plain English before I sign?
What happens if I need to update it later?

Red flags

Rushed process with minimal questions
Pressure tactics (“sign today”)
Vague promises with no written scope
No clear protections or process

How Soteria Estate Planning helps you avoid these mistakes (without the hard sell)

Our value isn’t “a document”. It is the parts most people miss when they go cheap:

A proper fact-find so the Will fits your real situation
Clear drafting that reduces ambiguity and future disputes
Guidance on executors, guardians, and (where needed) trusts
Step-by-step signing support so it’s legally executed correctly
A calm, human process - not transactional, not rushed

That is the middle ground many families want: professional quality and care, without paying for a full traditional solicitor model where it is not necessary.

Are DIY Wills legally valid?

They can be, if they are correctly drafted and properly signed/witnessed but the risk is that templates don not fit real-life complexity, and execution mistakes are common.

What is the biggest mistake people make with Wills?

Not making a Will at all because intestacy rules decide who inherits.

How do I make sure my Will won’t be challenged?

You cannot prevent someone from trying but you can reduce risk by making the Will clear, consistent, properly executed and aligned with your circumstances especially in blended families or where you are making unusual decisions.

Speak with a Will Writing expert today

Many people benefit from a professional Will-writing service such as the offering at Soteria Estate Planning. Understanding your last wishes takes time. We work with individuals and families to fully understand their situation and ensure correct execution of your last wishes regarding trusts, estates or disputes.

Book your Will Writing guidance call with a Soteria advisor today.

Biggest Will-Writing Mistakes People Make (And How to Avoid Them)