How to fill out Wyoming MV-401

Some things a person owns and wants to sell have no identification number at all - a trailer welded up in a shop, a vehicle assembled from two others, something factory-built whose number plate has rusted away. Nothing without a number can be titled, so nothing without a number can be sold with paperwork. This application is how Wyoming issues one. Two sides: applicant details and what sort of vehicle it is, then a statement of facts explaining where the components came from and why there is no number, and finally a law enforcement inspection block on the reverse. The department is explicit that a Wyoming number goes only to Wyoming residents, and equally explicit about what has to travel with the application - a photograph, a fee of $20.00, and proof of ownership of everything the thing was built out of.

Written against MV-401 (12/23), issued under WYDOT Motor Vehicle Services; a Wyoming identification number is issued only to Wyoming residents, and the titling that follows is done by the county clerk. The two questions the department is really asking are on the reverse, and they are not about metalwork. Where did the major components come from, and why did the person you got it from never title it. A statement of facts that answers those two plainly, with the bills of sale attached, gets a number. One that is vague about provenance gets a telephone call from a compliance officer, because an unnumbered vehicle with an unclear history is exactly what a stolen one looks like on paper.

Two documents, and they are not the same thing. Take the blank MV-401 from the dot.state.wy.us copy so you get the revision that is current today, then print our MV-401 guide and keep it beside you while you fill theirs in.

Step 1 · the form itself Blank MV-401 — Application for Assignment of Special Vehicle Identification Number (VIN) PDF at dot.state.wy.us · new tab Step 2 · how to fill it in Our filled-in MV-401 guide PDF · print and keep beside you

Filled in

What a completed one looks like

This is all 2 pages of the actual MV-401, rendered from the PDF the Wyoming Department of Transportation, Motor Vehicle Services publishes and completed end to end: letterhead, every field, and the blocks at the foot.

Amber — you write it
Grey — not yours to fill
Numbered — explained below

A completed Wyoming Application for Assignment of Special Vehicle Identification Number. The applicant is Verlene A. Tiegen of 1418 Cottonwood Loop, Sheridan, Wyoming 82801, with a location address and a mailing address the same. The homemade trailer box is ticked. The vehicle row reads make Homemade, body style Flatbed Trailer, year 2026 and two axles, with the licence plate column empty. On the reverse the statement of facts explains that the trailer was built new in the applicant's shop from mill-purchased steel with receipts attached, that no components came from another vehicle, and that it has never been titled because it did not exist until this year. The applicant has signed and dated it, and the entire law enforcement inspection block is washed grey. — Page 1 of 2. The front, completed for a flatbed trailer built from new steel. The department's own assigned-number block at the foot is washed grey.

Field by field

Every line, in the order you meet it

1
You fill this in
Check you are eligible before anything else
The residency line printed between the address blocks: a Wyoming number is issued only to Wyoming residents.
Watch out: The location address is the one that matters for the inspection. If the trailer is standing on a friend's place in another county, say so here rather than giving your own street twice.
2
You fill this in
Tick which of the two you are
Homemade trailer or trailer with a missing number, or other vehicles - and read the printed rules under whichever you ticked before filling in make and year.
Watch out: Factory-built with the number missing goes in whichever box fits the vehicle type, and the make is then the factory name rather than the word homemade.
3
You fill this in
The vehicle row
Make, licence plate number if there is one, body style, year and the number of axles.
Watch out: Unknown is not an acceptable year. For something you built, the year you finished it is the answer; for something assembled, the year of the oldest major component.
4
You fill this in
Assemble the documentation
A photograph of the completed vehicle or trailer, the $20.00 fee, proof of ownership of every major component, proof of year for an assembled vehicle, and an identification number inspection.
Watch out: Receipts for new steel count as proof that all materials are new, which is the branch of the rules a home-built trailer usually falls under. Keep them together in one envelope.
5
You fill this in
Answer the three questions on the reverse
Why the number is missing or why there is more than one, where the major components came from, and why the previous holder never titled or registered it.
Watch out: Attach a continuation sheet if you need one - the form invites it. A cramped answer squeezed into three lines reads as evasive even when it is not.
6
You fill this in
Sign the affidavit
Sworn under penalty of perjury that you are the owner or builder, that no stolen parts were used, and that everything supplied is true and correct.
Watch out: There is no notary on this form. The signature is enough - which is also why the felony warning above it is set in capitals.
7
Somebody else fills this in
Have law enforcement complete step seven
The officer records the make, year and vehicle type, the number found or its absence, where it was located and any additional numbers, then signs with a badge number, agency and date.
Watch out: A trailer made from a pickup box does not need this at all. Anything else does, and the officer needs to see the vehicle rather than photographs of it.

At a glance

What goes where

On the form	What to put in it
Applicant name, phone, and two addresses	Step one. The form asks for a location address and a mailing address separately, because the vehicle has to be somewhere an inspector can reach it.
The residency line	Printed between the two blocks and starred at both ends: a Wyoming identification number can only be issued to Wyoming residents.
Check one: homemade trailer, or other vehicles	Step two, and each choice comes with printed rules about what to write in the make and year boxes. Homemade, or the factory make name where the vehicle was factory-built and the number has gone; year completed for a homemade item, or the year of the oldest major component for an assembled one.
Vehicle make, licence plate number, body style, year and number of axles	Step three, one ruled row. The year box carries its own instruction - unknown is not acceptable.
Required documentation for all vehicles and trailers	Step four, five numbered requirements: a picture of the completed vehicle or trailer, a fee of $20.00 payable to WYDOT, proof of ownership with the statement of facts, proof of the year of the oldest major component for assembled vehicles, and an identification number inspection by law enforcement.
The proof-of-ownership branches	Four lettered sub-rules covering the original title or certificate of origin plus a copy of the bill of sale, what to do when there is no title, what to do when there is no bill of sale either, and what to produce where a trailer was made entirely from new components.
Statement of facts, three questions	Step five on the reverse: why the number is missing or why there is more than one, where and when and from whom the major components were obtained if you built it, and why the person you got it from never had it titled or registered.
The affidavit and signature	Step six: sworn under penalty of perjury that you are the owner or builder, that no stolen parts were used, and that the application and its supporting documents are true and correct - above a capitalised felony warning.
Law enforcement identification number inspection	Step seven, the whole lower half of the reverse: make, year, vehicle type, the number found or the words no VIN found, where it was located, any additional numbers and their locations, then the officer's printed name, agency, phone, signature, badge number and date.
For department use only	Assigned state number, by, and date, on the front. The department completes it.

What gets this one rejected

•Writing unknown in the year box. The box says in its own heading that unknown is not acceptable, and the form tells you what to write instead depending on which of the two boxes you ticked.
•Sending it without the photograph. It is the first of the five numbered requirements and the department has no other way of seeing what it is assigning a number to.
•Skipping the statement of facts because the answers seem obvious. Step four makes proof of ownership and completion of the statement of facts a single requirement - the narrative is part of the proof, not a covering note.
•Surrendering photocopies where originals are asked for. Original titles and certificates of origin for the vehicles used in the construction go with the application, all liens released, and in the applicant's name or assigned to them.
•Arranging an inspection for a trailer built out of a pickup box. The form exempts exactly that case, and the officer's time is better spent elsewhere.

Rules that decide whether it is accepted

•The fee is $20.00 and it goes to Cheyenne. Cash, cheque or money order payable to WYDOT, posted with the application and the documentation to Motor Vehicle Services on Bishop Boulevard. The checklist at the foot of step six ends by reminding you not to forget it.
•Make and year mean different things depending on the box you ticked. Homemade or the factory make name, and year completed or year of the oldest major component. There is also a special case for a vehicle over twenty five years old being registered as a custom - the year it resembles.
•The inspection can happen on this form or on law enforcement's own. Step four allows either: the block in step seven, or a separate identification number inspection form used by the officer's own agency.
•More than one number is a specific question. The inspection block asks the officer to list every number found and where each one is, giving the example of a new cab on a pickup - so that the titles surrendered with the application can be matched to the vehicles used in the construction.
•It only ends the paperwork at the department. The assigned number comes back from Cheyenne. Titling and registering the thing afterwards is a county clerk and county treasurer job like any other vehicle.

Every line here was read off MV-401 (12/23) itself — the PDF is here — and off the Wyoming Department of Transportation, Motor Vehicle Services pages. This is plain-language help with a form, not legal advice, and where our wording and the agency's differ, theirs governs.

Back to all Wyoming seller paperwork, or what selling a car in Wyoming involves.

How to fill out Wyoming MV-401

What a completed one looks like

Every line, in the order you meet it

Check you are eligible before anything else

Tick which of the two you are

The vehicle row

Assemble the documentation

Answer the three questions on the reverse

Sign the affidavit

Have law enforcement complete step seven

What goes where

What gets this one rejected

Rules that decide whether it is accepted

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