Guide
Letter of instruction: what it is, what belongs in it, and what must stay out
A letter of instruction is the document that tells the people you trust where everything is and what you wanted. It carries no legal authority — which is exactly why it can say the things a will cannot.
The short definition
It is the plain-English companion to your legal documents.
A will decides who inherits. A trust governs what it holds. A power of attorney names who may act. Each of those is a legal instrument, executed under the rules of your jurisdiction, and each is deliberately narrow.
A letter of instruction is none of those things. It is an ordinary document, written by you, in your own words, that tells whoever steps in where things are and how your life actually runs. It is not filed anywhere. It is not witnessed. It binds no one.
That lack of legal weight is the point. Because it is not an instrument, it can hold the practical detail no legal document has room for: which bank the everyday account is with, who the accountant is, which neighbour has a key, that the mortgage is on autopay from an account nobody else monitors.
A letter of instruction does not replace a will, a trust, a power of attorney, or an advance directive, and it confers no authority. Follow the execution and storage requirements that apply in your jurisdiction, and consult a qualified legal professional about anything with legal effect.
What belongs in it
Seven things worth writing down, roughly in order of urgency.
- Who to call first, and who backs them up if that person cannot be reached
- Where the signed originals live — the will, any trust, powers of attorney, advance directive
- The professionals already involved: attorney, accountant, financial adviser, physician, insurer, employer
- The institutions that hold something: banks, brokerages, pensions, mortgage, insurers — by name
- What continues automatically: subscriptions, autopay, direct debits, anything that keeps moving money
- Who depends on the household: children, an older parent, an animal, and what their routine is
- The wishes that are not legally binding but that you want known — a preference for arrangements, who should get a particular object, what to do with a business
The last one is where a letter of instruction earns its keep. Personal wishes placed inside a will can complicate probate and become public record. In a letter they stay private, and they reach the person who needs them without going through a court.
The safety rule
Write down where things are. Never write down what unlocks them.
There is an obvious temptation with a document like this: put everything in one place so nobody has to search. Passwords, PINs, account numbers, the safe combination.
Resist it. A letter of instruction is an ordinary piece of paper in an ordinary house. It gets photographed, emailed, carried between homes, and read by people who are not thinking about security because they are thinking about a funeral. A letter built from locations is useful to your family and close to worthless to a stranger. A letter built from credentials is a complete handover of your financial life to whoever picks it up.
Safe to write down
- Institution and professional names
- Where an original document is kept
- Last four digits, for identification
- Who is named in a role, and how to reach them
- Which secure system holds the real credentials
Never write down
- Passwords or master passwords
- PINs for cards or devices
- Two-factor or account recovery codes
- Full account or card numbers
- Full Social Security numbers
- Safe combinations, or where cash is hidden
Point instead: name the password manager the household uses and say who has been told how to reach it. That single line does the job of a page of credentials and costs nothing if the letter is found by the wrong person. It is the whole idea behind a safer information handoff.
Digital legacy planning follows the same rule: record which accounts and devices exist, which official legacy or recovery features are configured, and where the secure recovery system lives — never the passwords or recovery codes themselves.
Writing it
Four decisions produce something useful in about fifteen minutes.
Most letters of instruction are never finished, and the reason is structural: people start at the beginning, hit a question they cannot answer, and stop. A half-finished letter still helps enormously — but only if the half that got written is the half that matters.
So write these four first, in this order, and treat everything else as optional depth:
- Name the first call. One person, one backup, both told in advance.
- Record where the originals are. Not what they say — where they physically are.
- List the professionals and institutions. By name, with a number that works.
- Write down what continues. The obligations that do not pause for a crisis.
Then tell someone the letter exists and where it is kept. A finished letter nobody can find has solved nothing, which is the most common way this document fails.
Keeping it true
A letter written once and never revisited will send someone to a bank you left.
Information decays quietly. Rather than a calendar reminder you will ignore, tie a review to events that already have your attention: a move, a new job, a marriage or divorce, a death in the family, a new diagnosis, a change of attorney or accountant, a new mortgage or insurer.
When one of those happens, usually one line needs changing. That is the entire maintenance burden, and it is why the letter should be written in a form you can actually edit.
Common questions
What people ask before they write one.
Is a letter of instruction legally binding?
No. A letter of instruction carries no legal authority and binds no one. That is why it can hold practical detail and personal wishes that a will cannot, and why it never replaces a will, trust, power of attorney, or advance directive.
What is the difference between a letter of instruction and a will?
A will is a legal instrument that decides who inherits and is executed under the rules of your jurisdiction. A letter of instruction is an ordinary document that tells the people you trust where things are, who to contact, and what your non-binding wishes are. They do different jobs and work best together.
Should a letter of instruction include passwords?
No. Record where protected information lives — which password manager the household uses and who has been told how to reach it — rather than the credentials themselves. A letter built from locations is useful to your family and close to worthless to a stranger who finds it.
Where should a letter of instruction be kept?
Somewhere secure that the person you trust can actually reach, and tell them it exists. Keep the executed legal originals wherever your attorney instructs, and use the letter to record where those are.
A structured version
If a blank page is the obstacle, use one that asks the questions for you.
The Finder’s Book is a 250-page letter of instruction with the questions already written — fillable on screen or printable to complete by hand, and built on the pointer-not-a-vault rule above.
See the three editions Take the free Gap Check first
Prefer to start from the concepts? Read how The Finder’s Book works, the guide to important documents your family should be able to find, or what an in-case-of-death binder should contain.