This article describes the usage and the formation of the genitive plural case, aka monikon genetiivi.

1. Use of the Genitive Plural (minkä, keiden)

1.1. When indicating possession

The genitive is used to express someone possessing something. When there are multiple possessors, we use the plural genitive. When a group of words all belong together (say: a pronoun, an adjective and a noun), all three of them will be put in the genitive.

1.2. In front of postpositions

Postpositions in Finnish are often used to indicate location in relation to another object. Postpositions generally require their complement to be inflected in the genitive case.

1.3. When expressing necessity

In Finnish you will need to use the genitive with verbs expressing necessity (täytyy, pitää, kannattaa).

1.4. Important note

The singular genitive case also functions as the marker for the total object (e.g. Syön omenan; Luen kirjan). The plural genitive is NOT used in the same function. You will use the plural nominative or partitive for plural objects.

Please also check out this article: “When to use the plural genitive“!

2. The Formation of the Plural Genitive Case

The singular genitive’s marker -n also appears in the plural genitive. In addition to that -n, the plural genitive will also have the plural marker’s -i-. However, there are many possible options for how the genitive plural can look. In addition, different language sources will present them in a different way. This means that one source might list the plural genitive variants as: -jen, -ien, -eiden, -eiten and -sten. Another source might list them as -en, -den, -ten, -tten.

One thing that will make the genitive plural a little easier to learn is having studied the plural partitive already. Fairly often, the plural partitive’s and the plural genitive’s markers will have a similar look. Not included here is the plural genitive of long words.

2.1. Words ending in -u/-y, -o/-ö: add -jen

(In the plural partitive, these words would have -ja).

2.2. Words ending in -ä: replace the -ä with -ien

(In the plural partitive, these words would have -ia/-iä).

2.3. Words ending in -a

The same rules for grouping words ending in -a applies to both the plural partitive and the plural genitive: I call the two groups of words ending in -a by the names “kissa-words” and “koira-words”. These two words are easy to remember and each belongs to a different group of words ending in -a. If you can remember “kissa – kissojen” and “koira – koirien” and apply that rule to other, similar words, you’re on your way to mastering the plural genitive!

2.3.1. Words of two syllables (kissa-words): -ojen

Kissa-words are words of two syllables. Their final letter is -a. In the first syllable, you will have either -e-, -i- or -a-. In other words, the vowels of these words can look like:

• a…a (kana, maksa, sana, marja)
• e…a (herra, tela, teema, leija)
• i…a (kissa, tina, hinta, silta)

When you inflect these words in the plural genitive, you will replace the final -a with -ojen.

(In the plural partitive, these words would end in -oja).

2.3.2. Words of two syllables (koira-words): -ien

Koira-words are also words of two syllables. Their final letter is also -a. They differ when it comes to the first syllable: for koira-words you will have either -o-, or -u- in the first syllable. In other words, the vowels of these words can look like:

• o…a (koira, konna, honda, nokka)
• u…a (kukka, sukka, suora, juoma)

For koira-words, you will replace the final -a with -ien.

(In the plural partitive, these words would end in -ia).

2.4. Words ending in -i

Words ending in -i are once again divided into several groups. For most words, the -i will turn into -ien. However, there is often more than one option, of which one can be used in more poetic settings. The following rules only applies to short words. Long words (e.g. lääkäri, paperi) have their own rules.

2.4.1. New words ending in -i: add -en

(In the plural partitive, these words would end in -eja/-ejä).

2.4.2. Old words ending in -i: add -en

I have a more extensive list of words that belong to this type here.

(In the plural partitive, these words would end in -ia/-iä).

2.4.3. Old words ending in -si: add -en / -tten

In the partitive singular, these words end in -tta/ttä (e.g. käsi becomes kättä, and susi becomes sutta).
In the partitive plural,  these words end in -ia/iä (e.g. käsi becomes käsiä, and susi becomes susia).

I have a more extensive list of words that belong to this type here.

2.4.4. Old –li/-ni/-ri words: -ien or -ten

I have a more extensive list of words that belong to this type here.

2.5. Words ending in -e: add -iden or -itten

The genitive plural of words ending in -e have two possibilities: -iden or -itten. Of these, -iden is the most popular, though both are usually considered equally “correct”. The genitive plural of these words in strong.

(In the plural partitive, these words would end in -ita/-itä).

2.6. Words ending in -nen: replace the -nen with -sten

For words ending in -nen, there is also the possibility of using -sien for the plural genitive (iloisien suomalaisien naisien), but using -sten is much more popular (iloisten suomalaisten naisten).

2.7. Words ending in two vowels: -iden/-itten

These words have two possibilities: -iden or -itten. Of these, -iden is the most popular, though both are usually considered equally ”correct”.

2.8. Words ending in diphthongs -ie, -uo, -yö: -iden/-itten

These words have two possibilities: -iden or -itten. Of these, -iden is the most popular, though both are usually considered equally ”correct”.

(In the plural partitive, these words would end in -ita/-itä).

2.9. Longer words ending in two different vowels -eo, -uo, -yö:

This rule applies to words of multiple syllables. For these, you just add -iden or -itten to the end of the word without making any changes to the word itself.

2.10. Words ending in a consonant

2.10.1. Words ending in -s

Please look at this overview of words ending in -s: here.

For the plural genitive, you will have two different types of inflection, which you can identify based on their singular genitive form.

Words with -kse- in the singular genitive can have a plural genitive that’s based on its singular genitive (e.g. keskuksen → keskuksien), or based on its basic form (e.g. keskus → keskusten). I’ve provided the singular form (SG) in the table below for reference when you look at the plural form (PL).

Words with a long vowel in the singular genitive can have either -iden or -itten in the plural genitive.

2.10.2. Words ending in -ton/-tön

Words ending in -ton/-tön will get -ien added to their stem, which ends in -ttoma- (e.g. rahattoman, rahattomassa, rahattomalle). Note that we use the strong form of the word. It’s also possible to have -ten as the plural genitive ending for these words (e.g. työtönten), but this is very rare.

(In the plural partitive, these words end in -ia/-iä).

2.10.3. Words ending in -tar/-tär

Words ending in –tar/-tär will get -ien added to their stem, which ends in -ttare- (e.g. ystävättären, ystävättärellä, ystävättärelle)Note that we use the strong form of the word and remove the final -e. It’s also possible to have -ten as the plural genitive ending for these words (e.g. ystävätärten), in which case we use the weak form.

2.10.4. Words ending in -in

Words ending in -in can have two pretty different plural genitive forms: they can end in -ien or in -ten. This is tricky becaue the -ien ending will be added to the strong stem, while the -ten ending gets added to the weak stem. Both forms are used.

2.10.5. Words ending in -ut/-yt

Words ending in -ut can belong to two groups. The smaller of the two are words such as olut, kevyt and ohut. In the plural genitive, these words will end in -uiden and -uitten (both endings are allowed).

The much larger group are NUT-participles, such as väsynyt, kuollut, mennyt and juossut. These words will have –eiden or –eitten in the plural genitive. As you can see, the ending of both wordtypes ending in -ut is -iden or -itten, but the vowel right before the plural -i- is different.

2.11. Advanced: genitive plural’s -in

There is one more option for the ending of the plural genitive: -in. This is only possible with some words: words ending in an -a (in the singular) or in an -e (in the plural).

Usually this form appears in compound words as the first part (e.g. vanhempainilta, vanhainkoti, pyhäinpäivä). When not part of a compound word, it can sound old-fashioned.

3. Consonant Gradation in the Plural Genitive

The genitive plural will always be strong, both for wordtype A and wordtype B. That’s different than the partitive singular, where wordtype A words functions with the strong grade, and wordtype B with the weak grade.

I have a separate article on wordtype A.

I have a separate article on wordtype B.

Small note: the plural genitive of long words ending in -kka/kkä/kko/kkö can be weak.

That concludes the article on the plural genitive case!

If you want a chance to compare the genitive plural to the partitive plural, you can do so! There is also our page about the plural genitive of long words.

Related posts:

Finnish Postpositions – Edessä Takana Vieressä The Inflection of Postpositions – Finnish Grammar The Plural Genitive of Long Words The Plural Forms in Finnish – Examples