Where is the serial number on a Mercury outboard?
For most Mercury outboard engines 8hp and higher, the serial number is located halfway down the transom bracket on the right (starboard) side, just below the powerhead. On 6hp and smaller engines, it's found on top of the swivel bracket.
Many boaters take a quick photo of their serial number with their phone—this simple habit can save hours of troubleshooting when ordering parts.
We highly recommend you take a picture of your ESN tag and keep the photo on your mobile phone in case the tag becomes unreadable or if you need this information when you’re not near your boat.
**Are you looking for Mercury Outboard parts and products for your specific engine? Check out PartsVu's Mercury Maintenance Parts Library. Common maintenance parts and products are presented by engine model allowing you to easily find the parts you need.**
What About a Mercruiser Serial Number?
On a Mercruiser sterndrive or inboard engine, typically, the tag is on the block near the starter. But, sometimes, it's down by the starter on the engine block, near the flywheel, or on the flame arrestor.
All too often, the ESN tag on a Mercruiser is not the easiest to find, so definitely take a picture and save it on your cell phone.
**Are you looking for Mercruiser parts and products for your specific engine? Check out PartsVu's Mercruiser category page. We've worked to make it as easy as possible to find the parts and products you need.**
Why Do You Need to Know Your Mercury Serial Number?
Simply put, your Mercury serial number will allow you to identify and order the right parts for your engine model and year.
Mercury manufactures many, many different models and often variations of each model. While one thermostat might be the proper selection for some variations of a given engine model, there’s no guarantee that it will be compatible will all variations of that engine—knowing your Mercury serial number is the key.
As if matters weren’t confusing enough, sometimes Mercury will change an engine model design midway thru a given engine model year.
Therefore, Mercury Marine parts are often segmented by serial number ranges. Knowing your serial number will allow you to make sure that you are ordering the right parts, whether you are utilizing a Mercury engine schematic/Mercury outboard parts diagrams, the Mercury parts library, the complete list of Mercruiser parts library, or other resources.

How do I find out what year my Mercury outboard is by serial number?
To determine the year of your Mercury outboard, use the serial number on the engine and reference a Mercury Marine serial number-to-year chart. You can also enter the serial number into the Mercury Marine or PartsVu lookup tool to identify the exact year and model.
What is the serial number location on a Mercury 9.9 outboard?
The serial number for a 9.9hp Mercury engines is usually located on the top of the swivel bracket, which may require tilting the motor to see clearly.
Where is the serial number on a Mercruiser engine?
It’s typically found near the starter or flywheel, or on the flame arrestor. Always take a photo of it for safekeeping.
How can I identify my Mercury outboard by serial number?
Use the serial number lookup on the PartsVu Mercury Maintenance Library or the Mercury Marine parts catalog to determine the engine model and year.
What year is my Mercury outboard motor?
Once you locate the serial number, compare it against Mercury’s official serial number/year chart, or enter it online in a lookup tool.
Need parts for your Mercury engine? Shop all Mercury outboards at PartsVu.







423 comments
Hello i just picked up a 9.9 serial number 1R258839 and wondering what year it is i was told 2024 but i cant find a year on the engine anywheres
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PartsVu replied:
Hi Jordan,
Thank you for reading our blog and for reaching out to us. The serial number 1R258839 corresponds to a Mercury outboard motor manufactured on August 3, 2023.
If you have any further questions or need more information, feel free to contact us. We’re happy to help!
Best regards, PartsVu Team
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Hello i just picked up a 9.9 serial number 1R258839 and wondering what year it is i was told 2024 but i cant find a year on the engine anywheres
Hi there- looking for year for a potential purchase of a Mercury 15HP with serial number 0C231271.
Could you possibly provide some insight?
Appreciate it!
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PartsVu replied:
Hi Ivan,
Thank you for reaching out to us. The serial number 0C231271 corresponds to a Mercury 15HP outboard motor. Based on this serial number, the motor was manufactured in 1989.
I hope this helps with your potential purchase! If you have any further questions or need additional information, feel free to ask.
Appreciate your inquiry!
Jessica Zapatero PartsVu Customer service Manager 888-625-5460 PartsVu.com Monday – Friday 8:00 am to 5:00 pm
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Hi, could you please tell me the year of mfg of my 75hp Mercury 4 stroke engine
with serial # OT858260 ?
Thanks very much,
Gary
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PartsVu replied:
Hi Gary,
Thank you for reading our blog and for reaching out to us. The serial number 0T858260 corresponds to a Mercury 75HP 4-stroke outboard engine manufactured in 2003.
If you have any other questions or need further assistance, feel free to contact us. Thanks very much for your inquiry!
Happy Boating!
Jessica Zapatero PartsVu Customer service Manager 888-625-5460 PartsVu.com Monday – Friday 8:00 am to 5:00 pm
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Trying to find a part for my dad’s outboard mercury motor. Looking at the serial number it is either 0B107765 or 08107765. I cannot for the life of me figure out if the 2nd digit is a B or an 8. Any help would be greatly appreciated.
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PartsVu replied:
Hi Josh,
Thank you for reaching out to us. We understand how tricky it can be to differentiate between certain characters on a serial number. Generally serial numbers will include a letter after the first number and continue a sequence of numbers. Based on the options you’ve provided, it is more likely that the second digit is a “B,” making the serial number 0B107765. This serial number corresponds to a Mercury outboard motor manufactured in 1987. 90ELPTO
If you need help finding the right part or have any other questions, please don’t hesitate to contact us. We’re here to help!
Jessica Zapatero PartsVu Customer service Manager 888-625-5460 PartsVu.com Monday – Friday 8:00 am to 5:00 pm
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