A do not duplicate key authorization letter is a short signed note that tells a locksmith you are the key’s owner, names the specific person allowed to pick up copies, and states exactly how many duplicates may be cut. Keep it to one page. The locksmith needs to confirm three things from it: who you are, which key is involved, and who is permitted to walk out with a copy.
What to Include
A complete letter covers the following:
- Your full legal name, mailing address, phone, and email. If you are writing on behalf of a business or property, add the organization’s name and your title.
- Key identification: any key code, serial number, system name, or lock brand stamped on the key or listed in your lock contract. For a restricted system, include the manufacturer and your authorization card number if you have one.
- The full name of the person who will present the letter and collect the copies.
- The exact number of duplicates authorized. An open-ended number defeats the point of controlled duplication.
- A short reason for the request, such as a new maintenance hire or a replacement for a lost key. This is optional but helps the locksmith judge whether the request is reasonable.
- The date and your handwritten signature. A scanned or electronic signature is accepted by some shops, but an original is safer.
Plain language is fine. You do not need legalese, and padding the letter with it tends to make verification slower, not faster.
A Sample You Can Adapt
[Your Full Name]
[Your Address]
[City, State, ZIP]
[Phone Number]
[Email Address]
[Date]
[Locksmith Company Name]
[Locksmith Address]
[City, State, ZIP]
Re: Authorization to Duplicate Restricted Key
I, [Your Full Name], am the authorized key holder for the following key system:
Key System/Brand: [e.g., Medeco M3, Mul-T-Lock Interactive]
Key Code or Serial Number: [if applicable]
Property Address: [address where locks are installed]
Authorization Card Number: [if your system uses one]
I authorize [Authorized Person’s Full Name] to obtain [number] duplicate key(s) on my behalf. [Authorized Person’s First Name] will present a valid government-issued photo ID for verification.
This authorization expires on [date, typically 30 days out].
Sincerely,
[Handwritten Signature]
[Printed Name]
Add an Expiration Date
Most people forget this line and it matters. Without an expiration, a letter you wrote three years ago for an employee who no longer works for you can, in theory, still be used at the counter. A window of 30 days or less is reasonable for a one-time pickup. Write a fresh letter the next time you need copies.
What the Locksmith Will Ask For at Pickup
The person named in the letter brings it to the shop along with the original key and a government-issued photo ID. The locksmith matches the name on the ID to the name in the letter, checks the key details, and confirms the number of copies. For a restricted system, the locksmith may also contact the manufacturer to verify that your authorization card is active before ordering blanks.
Expect requests for additional proof that you actually control the property, especially for restricted systems, lock replacements, or master key changes. Documents commonly accepted include a photo ID matching the property address, a recent utility bill, a property deed, or mortgage paperwork. A property manager or business owner should bring something linking them to the address, such as a management agreement or a business lease.
Most shops keep the letter on file after the job is done. If you want the original back, say so before any cutting starts. Some locksmiths will return it with a stamp or notation showing the duplication was completed, which is useful for your own records.
Standard keys are usually cut on site in a few minutes. Restricted keys often take several business days because the locksmith has to order proprietary blanks from the manufacturer.
When the Letter Actually Controls Duplication
Before you rely on the letter, know what it can and cannot do. A “Do Not Duplicate” stamp on a standard key carries no legal weight in the United States. No federal law and no widely adopted state statute makes it a crime to copy a key bearing that phrase.1Medeco Security Locks. The Myth of Do Not Duplicate A conscientious locksmith may ask for your authorization letter anyway, but nothing prevents someone from taking the same key to an automated kiosk or a less careful shop and getting a copy. Kiosks do not scan for DND markings; if the blank is in the machine’s inventory, the key gets cut.
The letter does real work when the key belongs to a patented or restricted system. Those keyways are protected by utility patents, and only locksmiths licensed by the manufacturer can order the blanks.1Medeco Security Locks. The Myth of Do Not Duplicate The manufacturer keeps a list of authorized key holders, and your letter is the document that tells the locksmith a specific person has your permission to place an order against your account. Without it, the order cannot be processed regardless of who shows up at the counter.