Only a few words are regularly used as prepositions in Finnish, such as ennen (before). The associated noun is usually in the partitive case, for example ennen kesäkuuta (before June). Postpositions are more common, mostly used with the noun in the genitive, e.g. kesäkuun jälkeen (after June).
On the other hand, postpositions can be used as prepositions and vice versa. We can also say kesäkuuta ennen (with no change in style) and jälkeen kesäkuun (which is clearly poetic style).
Thus, we can say that Finnish does not have pure prepositions or postpositions. Instead, it has adpositions, which can be used either as prepositions or (more often) as postpositions.
Most adpositions in Finnish are originally case forms of nouns, and many of them are still in use as nouns, too. For example, jälkeen is the illative of jälki : jäljen (track, trace). Sentence analysis may be needed to decide whether such a word form is used as a noun or as an adposition.
An adposition used with a pronoun has the corresponding possessive suffix, if the pronoun is in the genitive, e.g. meidän jälkeemme (after us). This applies to standard Finnish; in spoken Finnish, it is common to omit the possessive suffix, e.g. meidän jälkeen. Some adpositions can also appear without an expressed pronoun, with just a possessive suffix, e.g. jälkeemme.
For adpositions with variant forms such as ali ∼ alitse, luo ∼ luokse, läpi ∼ lävitse, ohi ∼ ohitse, taa ∼ taakse, yli ∼ ylitse, the longer form must be used if a possessive suffix has to be added, e.g. luoksemme.
When the pronoun is in a case other than the genitive, no possessive suffix is used, e.g. ennen meitä (before us).
Possessive suffixes are not used with the following adpositions, even though they are used with the genitive: halki, kesken, poikki, ympäri. Thus, we say e.g. meidän kesken (between us).
The word to which a preposition or postposition relates to is most often in the genitive. Examples of this type of adpositions:
These adpositions are normally used as postpositions. Using them as prepositions, e.g. aikana sodan, is clearly poetic and would look odd in normal prose.
We will not list all the adpositions that require the associated noun in the genitive. Instead, we will next describe those adpositions that require some other case form.
The following adpositions are used with the noun in the partitive, whether used as postposition or as preposition:
Many of these words are also used as adverbs. For example, alas means most often just “downwards, down”, but it can also be used as an adposition, with a noun, e.g. alas Niiliä ∼ Niiliä alas (down along the Nile).
The case of a noun used with an adposition depends on the adposition, but it may also depend on word order, i.e. on the use of a word as a preposition vs. a postposition. To express “in the middle of the village”, we can say kylän keskellä, using the genitive of kylä (village) when followed by the postposition keskellä. Alternatively, we can use keskellä as a preposition, and then we use the partitive: keskellä kylää. There is not much stylistic difference between these alternatives. Usually postposition use is more common, except perhaps in some sayings such as keskellä kirkasta päivää (in broad daylight; literally: in the middle of bright day).
Other adpositions that are used with the genitive as postpositions and with the partitive as prepositions are keskeltä, keskelle, lähellä (near), läheltä, lähelle.
The following adpositions are used with the illative or the allative:
The case form used is usually the illative. The allative is used for location names that generally require outer locational cases, e.g. Tampereelle päin (towards Tampere), since we say Tampereella (in Tampere).
Normal adpositions are not used with the nominative, except for some foreign prepositions and some use of Finnish prepositions in a way that imitates foreign expressions. This includes:
Such usage is common in some forms of professional or academic language, but they are hardly suitable in texts for general audience.
The prepositions alle and yli are used in the nominative or (less often) in the genitive when they relate to a quantity, e.g. alle viisi ∼ alle viiden (less than five) and yli viisi ∼ yli viiden (over five, more than five). When expressing going below or over something, they always take the noun in the genitive, e.g. se meni pöydän alle (it went under the table), tien yli (across the street).
The adpositions vailla and vaille have mixed usage. They can be used to speak about something being without something or being left without something, and in such usage, the noun is in the partitive, e.g. vailla rahaa (without money). They can also express insufficiency, lack of some specific amount. In such usage, the missing amount is in the partive before the adposition and the amount “needed” appears after it, in a case form required by the context. Examples: grammaa vaille kilo (one gram less than a kilogram, i.e. 999 grams), viittä vaille kolme (5 [minutes] to 3 o’clock).
The adposition yli is used in a similar manner to express excess, but the expression before it is in the nominative and the expression after it is usually in the genitive, e.g. gramma yli kilon (one gram over a kilogram). When expressing time of day, the expression after the adposition can also be in the nominative, e.g. viittä yli kolmen ∼ kolme (6 past 3).
The adposition yli is also used in simpler contexts to mean just “over” or “across”, with the genitive as in sillan yli “over a/the bridge” or with the nominative when expressing that some amount is exceeded, e.g. yli tuhat euroa (over a thousand euros).
The following adpositions are mostly used as prepositions in normal style, all with the noun in the partitive:
Several infinitive forms of verbs are used in a manner that might be characterized as adposition use. The associated noun is then in a case form determined by the verb. For example, the word form riippuen is the II infinitive instructive of the verb riippua (to hang; to depend on), which requires the use of the elative case (suffix stA), e.g. Se riippuu säästä (It depends on the weather). Consequently, when riippuen is used as an adposition, the noun is in the elative, e.g. riippuen säästä (depending on the weather).
Adpositions of this type are mainly literary. Many of them are often criticized in language guides on various grounds; some of this is explained in the description of clause equivalents. However, many verb-based adpositions are rather common in written language, especially in formal prose. and also appear in spoken language. They are normally used as postpositions. Some examples:
As discussed in the descriptions of cases, Finnish often uses cases of nouns in situations where English uses a preposition. This applies to most uses of common prepositions like “of”, “to”, and “in”. However, especially for locational relations, there is often an alternative of using a postposition. For example, instead of the normal talossa (in a/the house) we can say talon sisällä; this is emphatic much in the same sense as the English “inside the house”. It can also be expressed by saying sisällä talossa, where sisällä (inside) is an adverb, not an adposition.
For locational relations of being below something or above something (as opposite to being just on it), Finnish uses postpositions: talon alla (under a/the house), talon yläpuolella (from above the house) etc. In some of such expressions, the second word can alternatively be described as a noun, such as yläpuoli (anything above something), so that the expression as a whole is just an expression like talon yläpuoli in a locational case.
The adposition kanssa typically corresponds to the preposition “with” in English. It is used with the genitive and always after the main word—it is hardly used as a preposition even in poetry, though its synonym kera appears as a preposition in poetic style.
Much of the use of kanssa has been described as inappropriate in language guides, due to reflecting foreign influence. In the most puristic approach, described e.g. in Terho Itkonen’s Uusi kieliopas, the word kanssa should only be used in adverbial constructs of the form A:n kanssa, meaning “in the company of A”, so that A and the subject of clause are more or less on an equal basis. So we can say “Hän saapui vaimonsa kanssa” (He arrived with his wife), but not “Hän tuli taskulampun kanssa” (He came with a flashlight)—a purist would instead say “Hän tuli taskulamppu mukanaan”.
As mentioned in the description of the adessive case, both the adessive and the postposition kanssa are often used to correspond to expressions like “A with B”, but such usage has been frowned upon in language guides. For example, to order coffee with milk, it is common to ask for kahvi maidolla, though some people may prefer saying kahvi maidon kanssa—and purists might say kahvi ja maito.