Welsh plurals might seem surprising when you first start learning the language.

Unlike English, which mostly just adds an “-s” to the end of a word, Welsh uses several entirely different methods to make words plural.

Sometimes you’ll add a suffix to the end of the noun.

Other times you’ll change the vowels inside the word itself.

In some unique cases, you actually drop letters to make a word plural.

This guide explains exactly how Welsh plural rules work so you can understand and apply them easily.

The most common plural suffixes

The most frequent way to make a Welsh noun plural is by adding a suffix to the end of the word.

There are over a dozen different plural suffixes in the Welsh language.

The most common ones you’ll encounter are -au, -iau, -on, -ion, and -oedd.

There’s no strict rule for which suffix belongs to which word, so you’ll need to learn the plural form alongside the new vocabulary word.

Here are some common examples of nouns that take suffixes.

Changing vowels to form plurals

Another very common way to create a plural in Welsh is by changing the internal vowels of the word.

You don’t add any extra letters to the end of these words.

The most frequent vowel changes you’ll see are from a to ei, a to e, or w to y.

If you speak English, this concept is similar to how “man” becomes “men” or “tooth” becomes “teeth”.

Words that drop a suffix to become plural

Welsh has a unique category of nouns where the singular form is actually longer than the plural form.

These are usually things that naturally come in large groups, like trees, animals, or vegetables.

For these words, the plural form is the base word.

To make them singular, you’ll add a suffix-usually -yn for masculine words or -en for feminine words.

Completely irregular Welsh plurals

Some Welsh words don’t follow any recognizable pattern when they become plural.

You simply have to memorize these words as you encounter them in your studies.

Unfortunately, many of these are some of the most commonly used words in the language.

Here are the most frequent irregular plurals you need to know:

You’ll see these irregular nouns constantly in written and spoken Welsh.

Regional variations in Welsh plurals

Welsh has distinct Northern and Southern dialects that sometimes affect plural endings.

In colloquial spoken Welsh, people often drop the final vowel sounds of plural suffixes.

For example, the common suffix -au is usually pronounced as an “e” sound in South Wales.

In North Wales, that exact same -au suffix is often pronounced as an “a” sound.

This means a word like pethau (things) sounds like pethe in the South and petha in the North.

This regional variation doesn’t change how the word is written in formal text.

It only affects how the plural suffix is spoken in everyday casual conversation.

Using numbers with plurals (a special rule)

Welsh has a very specific rule when it comes to counting objects.

When you use a number before a noun, the noun always remains in its singular form.

You never use the plural form of a word directly after a number in Welsh.

If you want to talk about three cars, you’ll use the singular word for “car” (car), not the plural form (ceir).

You only use the plural form when discussing the items generally, without a specific number attached.