How to Find and Read Mercury Outboard Serial Numbers

When you need spare or replacement parts for your Mercury outboard, the first thing you’ll need to know is your outboard’s serial number. The serial number allows you to find parts that fit your outboard motor based on year and horsepower. 

For example, Mercury manufactured more than 120 different models and variants of 225HP outboard in 2006. While one water pump repair kit might fit some of those models, there’s no guarantee it's compatible with your motor if you order it without knowing your outboard's exact serial number. Watch the video above or read on below to learn how to find and read Mercury outboard serial numbers.

To confuse matters further, Mercury has been known to change the design of a particular engine mid-way through a year. So a part that fits a specific Mercury outboard model manufactured in February of a given year may not fit the same model manufactured in October of that same year. However, once you know your Mercury outboard’s exact serial number, you can shop for OEM Mercury parts with the confidence that your order will be the right fit for your motor. Think of your engine’s serial number as its fingerprint: a means of identification unique to your particular outboard's make and model.

Finding Mercury Outboard Serial Numbers

All Mercury outboard engines either have an identification tag or an instruction plate that contains the serial number. The ID tag is located on either side of the swivel bracket (or transom bracket), and the instruction plate is located between the thumb screws above the steering tube. 

If the tag or plate has been lost or damaged to the point it can no longer be read, there’s a metal plug set in the powerhead that has the letter M and the serial number stamped into it. You’ll have to remove the top cowling to find it, and the precise location of the plug varies from motor to motor, but it’s usually easy to identify.

Understanding Mercury Outboard Serial Numbers

The sequence of letters and numbers (or just numbers) at the top of the identification tag or instruction plate is your Mercury outboard’s serial number. 

On newer Mercury outboards, the tag or plate will also show the motor’s year of manufacture below the serial number. Make sure you know the exact serial number for your motor every time you're ready to shop for OEM Mercury outboard parts.