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Boating Safety

HIN 101 For Boat Owners

Every new recreational boat sold in the USA and Canada, and many other countries, must have a Hull Identification Number (HIN).  This is a unique number identifying each boat, in much the same way that every automobile has a Vehicle Identification Number (VIN).  The US and Canadian rules for HINs are the same and the European Economic Community (EU) has adopted very similar rules.  But some boat owners get confused about HINs, especially on older boats that weren’t required to have them, and for home built boats.

In 1972 the Federal Boat Safety Act went into effect and as part of the act the U. S. Coast Guard was required to propose regulations for the safe construction of boats.  As a way to determine if a boat was in compliance, a HIN was required on each boat, and all boat manufacturers were required to obtain a Manufacturer Identification Code from the Coast Guard.  The HIN identifies the manufacturer and when the boat was made. Look here for the US Coast Guard version of HIN 101.

See Manufacturer Requirements at

Manufacturer Identification Codes: MIC

A Hull Identification number has twelve characters.  The first three letters are the Manufacturer Identification Code (MIC). In some older MICs there may be a number. You can look up a MIC here.  

 The last four numbers of an HIN show the date of certification. The date of certification is the date the manufacturer certifies that the boat meets all the rules that the particular boat has to meet.  But this kind of legal jargon is confusing to most people, so the last four digits, to most people, indicates when the boat was built.

The regulation was intended to apply to boat builders and manufacturers, not boat owners. But over the years boat owners became involved because states included the HIN in their registration process and wanted a HIN on every boat, even old and home made boats. So the regulation allows states to assign a HIN to boats that don’t have one.  Each state is assigned its own MIC to use when assigning a HIN. State MICs all start with the state abbreviation, such as NY, NJ, WN, FL,  and end in Z.  For example, a boat given a HIN by Washington would start with WNZ. The abbreviations used are not the US Postal Service abbreviations. They are the abbreviations used for boat registrations established in 1958.  See Old and Home Built Boats: State Issued HINs;  near the bottom of this page.

The HIN has also become a tool for law enforcement agencies to detect stolen boats, insurance fraud and other crimes.  Insurance companies use the HIN to identify boats that they insure.  So it has became important for all boats, old and new alike, to have a HIN. 

Who Assigns HINs and What Do They Look Like

Normally, a HIN is assigned by the builder or manufacturer. They keep a list of who the boats were sold to, by HIN. This is an effective tool for defect recalls, and for law enforcement checking bogus HINs.

So where does the boat owner come in?  This is not normally an issue with a brand new boat.  Most boats come with the HIN on the transom or, at or near the stern on boats with no transom.

 A HIN looks like this:


So, what does it all mean? ABC is the MIC.

The next five characters are anything the builder wants to assign. It can be 12345, or 00001, or 0000A, or 32001. Whatever they want to put in there except: O, I or Q. These characters look too much like zeros or ones. Some manufacturers use a sort of code in this area.  For instance, if they build a thirty footer and this is the first one then they would use 30001. Others just assign consecutive numbers, 00001, 00002, 00003, etc.

The ninth character identifies the month when the boat was certified (or built) as shown in the chart below. So if it's built in May the ninth character would be an E.

It works like this:

A: January

G: July

B: February

H: August

C: March

I: September (yes it's an I, but it's ok)

D: April

J: October

E: May

K: November

F: June

L: December

The tenth character is the last digit of the year when the boat was certified (or built). For example, if the year is 1997 then the tenth character would be a 7, or if it is the year 2009, it would be a nine.

Date Of Certification and Model Year

The date of certification is the date the manufacturer certifies that the boat meets all the regulations that the particular boat has to meet. What this means is: a manufacturer is required to certify, by placing a label on the boat, that it complies with all the regulations that apply to that boat.  The label says:

The boat complies with US Coast Guard Safety Standards in effect on the date of certification

This label is usually on the capacity label, for boats that have one, or at or near the helm station as a separate label, for boats not required to have a capacity label. The date of certification can be anytime between when the boat was begun until the date it leaves the place of build.  The law says the date of certification, and also the HIN, must be on the boat before it is sold, offered for sale or entered into interstate commerce.

So what does this have to do with model year?  Since the ninth and tenth characters are the date of certification, the model year has to agree with that date.

The last two characters are the model year. In the USA the model year is defined in the Code of Federal regulations as;

33 CFR 181.3 Model year means the period beginning August 1 of any year and ending on July 31 of the following year. Each Model year is designated by the year in which it ends.

Model Year

For a time, the U. S.  Coast Guard was not strictly enforcing the month portion of the definition of the model year. A builder could begin a model year in the month they wanted but it still could not differ from the year it was built. Most manufacturers started their model year in August, but some used June or July. One even started in May.  So for instance, a boat that was built between June, 1989 and May 31, 1990, would have been labeled a 1990 model.  But their model year began on June 1 and ended on May 31 of the next year.  The USCG always enforced the year portion of the model year definition. That is the model year on the HIN must fall within the year the model year ends.  Each Model year is designated by the year in which it ends.”

In 2009 the USCG ruled that the model year would be enforced as written in the regulation. The model year must begin August 1, and end July 31.  If the boat is a 2000 model year it shouldn’t say 1997 or if a boat is a 1997 model year it should not have a model year of 2000.  If it was built between August 1 of 2000, and July 31 of 2001, then it is a 2001 model year. If the model year differs from the date of certification, every time someone tries to register that boat, alarms will go off all over the place. The cops will come and start asking nosy questions. Also, the owner will have a difficult time insuring the boat. The insurance agent will suspect some sort of fraud if the model year is significantly different from the actual year built.

The exception to this is a boat that takes longer than a year to build.  Since this is really the date of certification, then the HIN does not have to be put on until the boat is finished and ready to leave the place of build.  In a large vessel this could be several years from the start of construction.  So, even though they started in 2002, if the boat was not finished until 2006, then it could be a 2006 model year or even a 2007 if it was finished after August 1, 2006.

Additions to HINs

There have been some additions to the HIN since 1984.  A builder can add info before and after the number.  For instance, many imported boats have a country code before the number.

US - ABC12345L409

This is a boat built in the USA.  If the two letters were CA it would be Canada.  The International Standards Organization (ISO) publishes a list of country codes.

Additionally they can put up to five characters after the HIN.

US - ABC12345L495 - H3266

It is rare to see a 17 or 19 character HIN but they do exist.The last five characters are a description of the boat and especially useful to law enforcement in tracking stolen boats.  The International Association of Marine Investigators has been trying for years to get the last five digits adopted by the US and the EU.  So far they have not been successful.

Old and Home Built Boats: State Issued HINs

What if you buy an old boat made before 1972, and it doesn’t have a HIN, or it was home built?  If you bought the boat, make sure you get a valid bill of sale from the seller.  If they have previously registered the boat you should also get the old registration. In states that Title boats the seller should also give you the title for the boat as well.  (By way, if a trailer comes with the boat you will need the same documents for the trailer).

They state may also ask for a Manufacturer’s Statement of Origin (MSO), or a Manufacturer’s Certificate of Origin (MCO). But these will probably only be available for a new boat, unless it is a Coast Guard documented boat. Then the boat may have a Coast Guard Builders Certificate.  Old boats or home built boats simply do not have these documents.  Only new, custom, or factory built boats have them.

If you built the boat you will not have any of these.  The state will ask you to fill out a form that attests that either you built the boat, or that it was built prior to 1972.    Some states will ask you for receipts for materials and parts as well to document that you actually built it. So document it by keeping plans, receipts, photographs and any documents related to the boat.

The state may also require someone to actually look at the boat and verify it exists.  This may mean bringing the boat on a trailer to their office, or if it is a large boat, having a law enforcement officer come to look at the boat.

The state will then assign a HIN to the boat. You will have to put the HIN on the boat in two places. The requirement is for the HIN to be placed on the upper right corner of the transom, or if no transom, at or near the stern on the right side below the gunwale.  A duplicate has to be put in a concealed location. Remember where this is.  If you ever sell the boat you will need to pass this on to the next owner.

It must be “permanently affixed”. This means put on in such a way that any efforts to remove or change it will be obvious.  It can be burned, etched, carved, or stamped.  You can put it on a plate or label as long as the plate or label cannot be removed.

HIN Location HIN Location on a canoe

Old HINs: HINs before 1984.

Just to confuse the issue even further, before 1984 there were two forms of the date of certification on the HIN.  It could look like this ABC000011272, or ABC00001M73E.   Both of these are valid and indicate a boat built in December 1972, (hence 12  and 72 on one, or M for model year 73, and E for the month of December).This was very confusing so in 1984 the current HIN was adopted.

Registration rules vary from state to state, so contact the state’s Boating Law Administrator.

See Also Registration / Documentation

Imported Boats

To make this even more muddied, imported boats are now entering the country with HINs that appear to be valid. They look just like US or Canadian HINs and they are valid in the country of origin, but not in the USA.  All Canadian HINs are valid in the US and vice versa.  Why aren’t most foreign HINS valid?  It goes back to the MIC. The US and Canada have a shared MIC code database. Since 1972 the US and Canada have assigned approximately 40,000 MICs.  At any one time only about 4500 are active, but companies go in and out of business daily.   

Then the International Standards Organization (ISO) adopted the MIC assignment system. The European Union (EU) incorporated this in their code called the Recreational Craft Directive.  Each EU country is now assigning MICs to their boat manufacturers.  Many of these are identical to MICs assigned by the US and Canada.  So a boat with a MIC of ABC may have been made in any of several dozen countries. An HIN on a foreign built but will usually have a country code before the 12 digit HIN, as in GB - ABC12345L495, meaning it was made in Great Britian

The rule in the US is that the importer is supposed to get a MIC from the US Coast Guard and assign valid HINs to the boats.  Unfortunately this is sometimes not done and there are thousands of imported boats sold each year in the US with invalid HINs.  This becomes a problem when the owner attempts to register the boat with a state or document it with the Coast Guard.

So, if you buy an imported boat and it has a foreign HIN (other than Canada) you may be asked a lot of questions when you try to register or document it.  If the HIN is not valid, you may have to contact the US Coast Guard (or Canadian Coast Guard), Office Of Boating Safety to get it straightened out and get a valid HIN for the boat.  If you import the boat yourself, you will have to get a valid HIN.  If you are going to register it with a state they will assign a state HIN.  If documenting the boat the USCG may have to assign a valid HIN.  

HIN Errors, Mistakes and Bogus HINs

So, what to do if you get a boat with a bogus HIN, that is, there is a valid error in the number, or someone altered the HIN?  People have been caught altering HINs to make the boat a newer model, or to try selling a stolen boat.  The best thing to do is contact the boating authority in your state, the local law enforcement, and the US Coast Guard Office of Boating Safety 202-372-1077.  Make every attempt to get this straightened out, because if you don’t it will come back to haunt you.  Suppose you get boarded and they run the HIN?   Or, you get a safety check by local law enforcement at a boat ramp and they discover the bogus HIN,  or you try to sell the boat. The boat may be impounded, it won’t be returned to you until the investigation is complete and you are cleared. If the boat has been stolen you may never get it back because it will be returned to it's legal owner. So, deal with this as soon as you discover the problem.


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