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Terms of business.

Price list - Motor Cruisers, Sports Boats, PWC & Sailing Yachts.

Price list - Narrowboats, Broadbeams & Dutch Barges

Broker registration form.

Broker enquiry form.

Where to find your British Ships Registration - Part One official number.

About Small Ships Part Three register.

Recreational Craft Directive.


Hull Identification Numbers:

Identifying a vessel:


The Hull Identification Number or HIN, is a unique combination of letters and/or numerals affixed or embossed on the outside of the transom, generally on the starboard side above the waterline on most vessels.

Pre-Recreational Craft Directive – until 16th June 1998 boats generally have twelve digits.

RCD compliant vessels – 16th June 1998 onward have fourteen digits.

Serial numbers of all kinds are vital, as they provide the only definitive way to individually identify your vessel. Many times serial numbers are incorrectly quoted and this can lead to subsequent confusion.

Other numbers on your vessel should be recorded for your own records, but can also be of use when trying to identify a stolen or missing vessel.


Pre-Recreational Craft Directive – until 16th June 1998

Pre-Recreational Craft Directive – until 16th June 1998 boats generally have twelve digits but:

Older vessels are sometimes marked with identification serial numbers which often have less characters and are presented in different formats. For example, Fairline Boats used a five or six character number or yard/build number.

Other larger manufacturers each had their own system and it is difficult to summarise every number configuration used. Often this number is displayed on the transom, in the cockpit or often on a plate within the cabin.

Some speedboat manufacturers used a combination of model, serial number and year in their serial numbers (for example Fletcher used a simple model/serial number/year format on many models). This was presented on a plate on the dashboard.


 Recreational Craft Directive compliant vessels – 16th June 1998 onward

Hull identification serial numbers should on all vessels built after 16th June 1998 appear in the international ISO format with fourteen characters. The prefix should be the country code followed by the MIC (Manufacturers code) – three letters. This is followed by the production model and serial number followed by the month of production and year of production or model year.

This is set out in this example:

GB –MPP1A01234F001

GB (country code) Great Britain – MPP (Manufacturers Code,name), 1A (Model)1234 (serial no.) F (month of build), 001 (year of manufacture).

This hull identification number should always appear on the transom permanently moulded or etched into the hull and occasionally on a permanently affixed plate. This is in the majority of cases to the starboard side of the transom.

A second plate is often affixed within the vessel in a location known only to the manufacturer and sometimes the police.

Some steel/aluminium vessels (often narrowboats) have this identification number stamped into one of the surfaces within the engine room.


Personal Water Craft 

All personal Water Craft utilise the standardised Hull identification numbering format used by US boat manufacturers and which is almost identical to the ISO standard. The hull identification number is found on the aft section of every PWC on a plate and the inboard engines also carry a serial number stamped into the engine block or marked on a plate. In addition many PWC’s are fitted with ‘Datatag’ which carries the principle identification data.  


 Out boards:

          In almost every case the serial number plate will be affixed to the engine swivel bracket either on a riveted plate or sticker and is obviously marked with the model and serial number code.


Chrysler outboards – Model number of two to four characters followed by five or six digit serial number. The same system was used by Force (the successor to Chrysler).

Example: 709HA - 1234


Evinrude – These engines use a model code followed by a serial number. The usual format includes a four or five character model code (e.g. 4386C) followed by a serial number prefixed by the letter C or B and then six digits More recent Evinrudes have adopted a slightly different system.

Example: E15BALCIS – B123456


Johnson  - These outboards were produced by the same group as Evinrude (OMC). The serial and model number format though similar, generally prefixed the serial number with a single letter prefix, followed by a five or six digit serial number.

Example: BJ90TLECS – R12345678


Honda – These engines usually prefix with a four character model code (e.g. BBBL) followed by a six or seven digit serial number.

Example: BBBL -1234567


Mariner – These engines were originally a mix of Mercury and Yamaha serial numbering systems though more recent engines follow the Mercury system. Some Yamaha origin engines prefix with a Yamaha style three or four character model code followed by a six digit serial number. Mercury based engines always use a typical Mercury system prefixing the serial number with OB then six digits.

Example: OB123456


Mercury – These engines always use a six digit serial number prefixed by OB or OC etc.

Example: OB123456


Suzuki – These engines usually prefix with a two to six character model code (e.g.DT60) followed by a seven digit serial number.

Example: DT40 RL - 0034567


Tohatsu – These engines usually have a two or three character model code (e.g. 4MS) followed by a five digit serial number.

Example: 4MS - 12345


Yamaha – These engines usually have a model code prefix of up to seven letters/numbers (e.g. 80AETL) followed by a six digit serial number.

Example: 80AETL - 123456




Nearly all inboard engines have at least two numbers of importance. These are the engine serial number and the gearbox serial number. If your vessel has an out-drive installation you also need to concern yourself with the out-drive serial number(s) and the transom shield number(s).

Serial numbers are always marked on inboard engines either on a riveted plate somewhere on the block and sometimes by being stamped into the engine block. These numbers often appear also on stickers placed on the head or intake housing so that they are conveniently accessible.


Caterpillar – These engines usually have a eight character serial number prefixed  with a model code.

Example: 13K123445


Cummins  - These engines usually have a simple eight digit serial number system – Example: 12345678


Mercruiser – These engines utilise a standardised two character prefix to all their component numbers. There are always six digits after the prefix.

Example: OM123456

OMC - These engine installations usually use a seven digit serial number often prefixed by the letter ‘T’. Similarly the transom shield and outdrives have a similar system in place.

Example: T1018006


Perkins - These engines use a model prefix (e.g. 236T) followed usually by a seven or eight digit serial number.

Example: 236T U 1234567


Volvo Penta – These engines use a lengthy serial number system usually starting 220 or similar with up to eleven digits in all. The model code usually appears as a combination of letters and digits e.g. AQ200D or KAD32 etc.

      Example: AQ220D 4130560



If you have trouble finding this number please ask your local surveyor or broker for help. They may well be able to come to your vessel to locate it for you.

Alternatively please telephone us on 01454 ……….

 Or E-mail us at: enquiries@yachtdata.co.uk


The yachtdata team.



The yachtdata team. Telephone 01454 269696.
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