Finnish does not leave foreign words alone. A borrowed noun still has to wear the case endings like any native word, so it must first be fitted with a Finnish stem to hang them on. Most established loans have already been fitted — they end in a Finnish vowel and inflect as if they were homegrown. The genuinely tricky cases are recent borrowings and foreign names, which sometimes need a linking vowel, a colon, or an apostrophe before an ending can attach. This page sorts the settled loans from the awkward ones.
Settled loans inflect like native words
A loan that has been in the language for a while has usually acquired a final Finnish vowel, and once it has, it declines like any comparable native noun. Bussi (bus), filmi (film), hotelli (hotel), auto (car), and nailon (nylon) all take ordinary case endings.
| Nominative | Genitive | Inessive (in) | Partitive |
|---|---|---|---|
| bussi (bus) | bussin | bussissa | bussia |
| hotelli (hotel) | hotellin | hotellissa | hotellia |
| filmi (film) | filmin | filmissä | filmiä |
| auto (car) | auton | autossa | autoa |
Aamulla bussissa oli niin täyttä, että jäin odottamaan seuraavaa.
On the bus this morning it was so packed that I stayed to wait for the next one.
Varasin huoneen pienestä hotellista meren rannalta.
I booked a room in a small hotel by the sea.
Watch filmi: it contains only the neutral vowel i, and a word with only neutral vowels counts as front for harmony. So its endings are front — filmissä, filmiä, never filmissa. Bussi and hotelli, which contain u and o, are back — bussissa, hotellissa.
Consonant-final loans take a linking vowel
A loan that ends in a consonant cannot take a vowel-initial ending directly — Finnish stems end in a vowel. So a linking vowel, usually -i-, is inserted before the ending. Nailon becomes nailonin, nailonissa, nailonista.
Takki on tehty nailonista, joten se kuivuu nopeasti.
The jacket is made of nylon, so it dries quickly.
The same happens with many recent technical and English borrowings that keep a consonant ending: the -i- is what lets the case ending grip.
The loan trap: gradation that doesn't happen
Native Finnish words alternate their k, p, t — tauti becomes taudin (t → d), satu becomes sadun. By that logic auto "should" become audon in the genitive. It doesn't: the genitive is auton. Many loans simply resist consonant gradation, keeping the strong consonant where a native word would weaken it. This is one of the few places where knowing a word is a loan actually helps you predict its behavior.
Auton moottori ei käynnisty tässä pakkasessa.
The car's engine won't start in this cold.
Foreign place names: the -seen illative for -oo and long vowels
Foreign place names inflect too, and one pattern surprises everyone. A name of two or more syllables ending in a long vowel — the many Finnish and foreign -oo names among them — forms its illative ("into / to") not with a doubled vowel but with the long ending -seen.
| Name | Illative (to / into) | Inessive (in) |
|---|---|---|
| Lontoo (London) | Lontooseen | Lontoossa |
| Porvoo | Porvooseen | Porvoossa |
| Espoo | Espooseen | Espoossa |
Lennämme ensi kesänä Lontooseen viikoksi.
Next summer we're flying to London for a week.
Muutimme viime vuonna Helsingistä Porvooseen.
Last year we moved from Helsinki to Porvoo.
The pull toward Lontoon is strong for English speakers because -n is the "normal" way you've seen endings attach — but Lontoon is the genitive ("London's"), not the illative. "To London" is Lontooseen. See illative formation for when each illative shape applies.
The colon: acronyms and initialisms
An acronym read as a string of letters keeps its capital spelling and joins the ending with a colon, matching the pronunciation of the final letter. EU (pronounced ee-uu) ends in a back vowel sound, so its endings are back: EU:ssa, EU:hun. USA likewise gives USA:ssa, USA:han.
Sisareni on töissä EU:ssa Brysselissä.
My sister works at the EU in Brussels.
The apostrophe: silent letters and doubled vowels
When a foreign name ends in a letter that is silent or pronounced as a vowel, the ending is added according to the sound, and an apostrophe marks the boundary so the reader isn't misled by the spelling. Bordeaux is pronounced [bordoo], ending in a long vowel despite the written -x; so "in Bordeaux" is Bordeaux'ssa. The English word show, whose w is pronounced as a vowel, gives show'ssa, show'n.
Kävimme kesällä Bordeaux'ssa maistelemassa viinejä.
In the summer we went to Bordeaux to taste wines.
Nappasin idean uuden ohjelman show'sta.
I got the idea from the new program's show.
Common Mistakes
❌ Lennämme Lontoon.
Incorrect — Lontoon is the genitive ('London's'); the illative 'to London' is Lontooseen.
✅ Lennämme Lontooseen.
We're flying to London.
❌ Ostin viime viikolla uuden audon.
Incorrect — auto resists gradation; its genitive is auton, not audon.
✅ Ostin viime viikolla uuden auton.
I bought a new car last week.
❌ Sisareni on töissä EUssa.
Incorrect — an acronym joins the ending with a colon: EU:ssa.
✅ Sisareni on töissä EU:ssa.
My sister works at the EU.
❌ Kävimme Bordeauxissa.
Incorrect — the -x is silent; add the ending to the sound with an apostrophe: Bordeaux'ssa.
✅ Kävimme Bordeaux'ssa.
We went to Bordeaux.
❌ Takki on tehty nailonsta.
Incorrect — a consonant-final loan needs a linking vowel before the ending: nailonista.
✅ Takki on tehty nailonista.
The jacket is made of nylon.
Key Takeaways
- Settled loans with a Finnish final vowel inflect like native nouns: bussi → bussissa, hotelli → hotellista.
- Only-neutral-vowel loans count as front: filmi → filmissä, not filmissa.
- Consonant-final loans take a linking -i-: nailon → nailonissa, nailonista.
- Many loans resist gradation: auto → auton (not audon), unlike native tauti → taudin.
- Two-syllable-plus names in a long vowel take the -seen illative: Lontoo → Lontooseen, Porvoo → Porvooseen.
- Use a colon for acronyms (EU:ssa) and an apostrophe for names with a silent or vowel-sounding final letter (Bordeaux'ssa, show'ssa).
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Start learning Finnish→Related Topics
- Exceptions, New Loanwords and Blocked GradationB2 — Where gradation does NOT happen: blocked clusters (posti→postin, matka→matkan), non-gradating loans (auto→auton), and the special poika→pojan k-loss.
- Forming the Illative: The Trickiest EndingB2 — The full illative algorithm: double the vowel (taloon), add -hVn (maahan) or -seen (huoneeseen), plus the plural -ihin/-siin — Finnish's trickiest ending.
- Proper Nouns and Their InflectionA2 — Finnish names decline and gradate like common nouns (Helsinki → Helsingissä); some cities take exterior cases (Tampereella), and foreign names use ' or :.
- Noun Type Classes: A Reference MapC1 — A consolidated map of Finnish declension types — nominative, genitive, partitive, and stem for the dozen patterns behind the KOTUS dictionary type numbers.
- Letters Only in Loanwords: B, C, F, Q, W, X, Z, ÅA1 — Eight letters outside Finnish's native sound system — how older loans dropped them (koulu, kahvi), how newer loans keep them, and why they always take Finnish pronunciation.