Maine Coon Color Codes Explained: EMS, CFA, and What Those Letters & Numbers Mean

If you’ve ever looked at a Maine Coon pedigree, breeder page, or registration paperwork and seen something like “MCO ns 22” or “d 09 24,” you’re not alone. Those combinations can look like secret agent passwords. But they’re actually a standardized way breeders and cat registries describe a cat’s breed, color, pattern, and white spotting with precision.

This guide breaks it down in plain English so you can confidently decode color codes, whether you’re researching kittens, reading a pedigree, or just curious about your own cat.

Quick Answer: What Are Maine Coon Color Codes?

Maine Coon color codes are shorthand systems used by breeders and registries to describe a cat’s breed + base color + modifiers (like silver) + pattern + white spotting. The exact format can vary by registry (EMS/FIFe, GCCF, CFA, etc.), but the goal is the same: clear, consistent identification.

The 3 Main Parts of a Color Code

Most Maine Coon coat codes are built from these core pieces:

1. Breed code (example: MCO = Maine Coon in EMS-style systems)

2. Base color letter (example: n = black, a = blue, d = red)

3. Numbers that describe pattern and/or white spotting (example: 22 classic tabby, 09 low white spotting)

   
   

Once you learn those pieces, the code becomes surprisingly logical.

Step 1: Breed Code (What Does “MCO” Mean?)

In EMS-style coding, MCO simply means Maine Coon. It usually appears at the start of the code before color and pattern details.

Step 2: Base Color Letters (The “Main Color”)

Here are common EMS base color letters you’ll see for Maine Coons:

• n = black (also used as the base for brown tabby)

• a = blue (dilute black, gray tone)

• d = red (orange/ginger)

• e = cream (dilute red, pale apricot)

• f = black tortie (black + red patches, typically female)

• g = blue-cream tortie (dilute tortie)

• w = white

  
  

You may also see notes that some colors (like chocolate/lilac) aren’t used/accepted in Maine Coons under many standards.

Step 3: Modifiers (Extra Letters That Change the Look)

Modifiers are add-on letters that adjust the base color. The most common one you’ll see:

• s = silver (changes pigment distribution, creating silver tabby or smoke effects)

• y = golden (warmer undercoat, rarer)

  
  

Silver vs Smoke (Simple Explanation)

• Silver tabby: the hairs have lighter bases, and the tabby pattern appears on a bright background.

• Smoke: often looks solid until the coat parts, showing a pale/silver undercoat.

  
  

Step 4: Pattern Numbers (Tabby Types and More)

In EMS-style systems, numbers often describe tabby pattern and related coat effects.

Common tabby codes include:

• 21 = agouti/tabby unspecified

• 22 = classic/blotched tabby (swirls “bullseye” style)

• 23 = mackerel tabby (vertical stripes)

• 24 = spotted tabby (spots or broken stripes)

• 25 = ticked tabby (no strong stripes on the sides)

  
  

You may also see:

• 11 shaded

• 12 shell

  
  

Step 5: White Spotting Codes (How Much White?)

White spotting is often indicated by codes like 01 / 02 / 03 / 09, which indicate the amount/location of white.

A simple way to think about it:

• 01 = very high white

• 02 = harlequin-level white

• 03 = bicolor (noticeable white)

• 09 = low white (small patches like chest/paws)

  
  

(Exact naming can vary by registry, but the “more white vs less white” concept holds.)

Real Examples: Decode These Like a Pro

Here are examples you might actually see:

Example 1: MCO ns 22

• MCO = Maine Coon

• n = black

• s = silver

• 22 = classic tabby

• 
  

Meaning: Black Silver Classic Tabby Maine Coon.

Example 2: MCO a 23

• a = blue

• 23 = mackerel tabby

  
  

Meaning: Blue Mackerel Tabby Maine Coon.

Example 3: MCO d 09 24

• d = red

• 09 = low white spotting

• 24 = spotted tabby

• 
  

Meaning: Red-spotted tabby with White.

Example 4: MCO ns (no pattern number listed)

• n = black

• s = silver

• No tabby number shown

  
  

Often used to indicate a smoke look (black smoke).

EMS vs CFA: Are the Codes the Same?

Not exactly. Different registries use different systems and naming conventions. EMS-style codes (often associated with FIFe/EMS) commonly use the letter/number format we’ve discussed, while CFA uses its own classifications and references, so the same cat may be described differently depending on registry paperwork.

The good news: once you understand base color + modifiers + pattern + white, you can translate between systems much more easily.

Why Understanding Color Codes Matters (Especially for Buyers)

Knowing the code helps you:

• Understand what you’re actually getting (and paying for)

• Predict coat changes (silver/smoke/shaded can change a lot from kitten to adult)

• Avoid confusion with non-standard colors for the breed

• Read pedigrees and registration papers with confidence

  
  

How to Decode Your Cat’s Code in 30 Seconds

1. Identify the breed (MCO)

2. Find the first letter = base color

3. Look for modifier letters like s (silver)

4. Read the numbers for tabby pattern (22/23/24/25)

5. If you see 01/02/03/09, that’s white spotting level

   
   

Put it together, and you’ve decoded the coat.

FAQ

What does “MCO” mean?

It means Maine Coon in EMS-style coding.

What do the letters mean?

They describe base color (like n black, a blue, d red, e cream), and modifiers (like s silver).

What do the numbers mean?

They usually describe tabby patterns and/or white spotting. For example, 22 can refer to classic tabby, and 03/09 can refer to levels of white spotting.

Are color codes the same in every registry?

No, different registries use different systems, but the underlying “color + pattern + white” logic is consistent.