Irish numbers use three distinct systems depending on exactly what you are counting.

This often surprises beginners who expect a single set of numbers like in English.

You must choose a different set of numbers to count out loud, count objects, or count people.

Learning these three systems early on will make speaking Irish much easier.

I’ll walk you through each of the three Irish counting systems with clear examples.

System 1: counting out loud (independent numbers)

The first system is used when you’re just saying numbers by themselves.

You’ll use this system to count from one to ten, read a phone number, or do math.

In this system, you must place the particle a before the number.

When the number starts with a vowel, the particle a causes a change called h-prothesis.

This simply means you add an h to the beginning of the word to make it easier to say.

You’ll see this happen with the numbers one and eight.

Here are a few examples of how you use these independent numbers in a sentence.

System 2: counting objects (non-humans)

The second system is used when you’re counting physical things like cars, animals, or houses.

You drop the particle a completely when placing a number directly in front of a noun.

The words for two and four also change their spelling in this system.

A dó becomes dhá and a ceathair becomes ceithre.

Another rule that surprises English speakers is that you mostly use the singular form of the noun after numbers.

Instead of saying “three boats”, you literally say “three boat” in Irish.

These numbers also cause beginning letters to change through lenition or eclipsis.

Numbers one through six cause lenition, which means you add an h after the first consonant of the noun.

Numbers seven through ten cause eclipsis, which means you add a new consonant to the very beginning of the word.

Here’s an example using the word bád (boat).

Take note that when counting just one item, we sandwich the noun between aon and amháin.

Here are some examples of counting objects in a full sentence.

System 3: counting people (personal numbers)

The third counting system is used exclusively for counting human beings.

You can’t use these numbers for animals, objects, or concepts.

These words are special nouns that already have the meaning of “people” built into them.

Because of this, you rarely need to add the Irish word for person after the number.

For the number one, we simply use the standard word for person, which is duine.

If you want to specify exactly what kind of people you’re counting, you add the noun right after the personal number.

Here are a few examples showing how to use personal numbers in everyday situations.