Kosten ("to cost") is one of the first verbs you need when you start spending money in German, and you reach for it every time you ask a price: Was kostet das? It is a fully regular weak verb, which is good news — once you learn the small spelling adjustment its -t stem forces, every form is predictable. The one genuinely surprising thing about it for English speakers is its government: the price is in the accusative, not the nominative, even though English treats "it costs a euro" as a kind of equation.
Principal parts
| Infinitive | Präteritum | Partizip II (auxiliary) |
|---|---|---|
| kosten | kostete | gekostet (hat) |
Read this as kosten – kostete – hat gekostet. The Perfekt auxiliary is haben (you "have cost" something a price; there is no motion or change of state that would call for sein). For why ordinary verbs use haben by default, see haben vs sein in the Perfekt.
The -t stem and the "support -e-"
The stem of kosten ends in -t (kost-). When a German verb stem ends in -t or -d, you would otherwise have to pronounce impossible clusters like kostt or kostst. German solves this by inserting a support vowel -e- before the endings -st and -t. This is why you see du kostest and er kostet rather than du kostst / er kostt. The same rule shapes the whole Präteritum (kostete) and the participle (gekostet). For the full pattern across all such verbs, see verb stems ending in -t, -d, -s.
Präsens (present)
| Person | Form |
|---|---|
| ich | koste |
| du | kostest |
| er / sie / es | kostet |
| wir | kosten |
| ihr | kostet |
| sie / Sie | kosten |
In practice the verb is used overwhelmingly in the third person — things cost, people normally don't — so kostet and kosten are the forms you will actually say.
Was kostet das?
How much does this cost? (the single most useful shopping phrase; informal/neutral)
Die zwei Tickets kosten zusammen achtzehn Euro.
The two tickets cost eighteen euros together. (plural subject, so kosten)
Wie viel kostet der Versand?
How much is the shipping? (neutral, e.g. online checkout)
Präteritum (simple past)
A regular weak Präteritum with the support -e-: stem + -ete + endings.
| Person | Form |
|---|---|
| ich | kostete |
| du | kostetest |
| er / sie / es | kostete |
| wir | kosteten |
| ihr | kostetet |
| sie / Sie | kosteten |
In speech, Germans usually reach for the Perfekt for past events, but with kosten the Präteritum kostete is also common, especially in writing and in price comparisons. See the weak Präteritum for the general pattern.
Damals kostete ein Liter Benzin noch keine zwei Mark.
Back then a litre of petrol still cost less than two marks. (narrative past, common in reminiscing)
Perfekt (present perfect)
Present of haben + the participle gekostet.
| Person | Form |
|---|---|
| ich | habe gekostet |
| du | hast gekostet |
| er / sie / es | hat gekostet |
| wir | haben gekostet |
| ihr | habt gekostet |
| sie / Sie | haben gekostet |
Die Reparatur hat über dreihundert Euro gekostet.
The repair cost over three hundred euros. (Perfekt with haben — note the support -e- in gekostet)
Konjunktiv II (would cost)
The synthetic Konjunktiv II of a weak verb is identical to its Präteritum (kostete), so to keep it unambiguous Germans almost always use the würde-form: würde kosten. For why the analytic form wins here, see the würde-form.
| Person | würde-form |
|---|---|
| ich | würde kosten |
| du | würdest kosten |
| er / sie / es | würde kosten |
| wir | würden kosten |
| ihr | würdet kosten |
| sie / Sie | würden kosten |
Ein neuer Motor würde mehr kosten als das ganze Auto wert ist.
A new engine would cost more than the whole car is worth. (hypothetical, würde-form)
Government: the price is accusative
This is the point English speakers most need to internalise. The thing that costs is the subject (nominative), and the price is a direct object in the accusative. You can see this with masculine nouns, where the accusative is visibly marked:
Das Buch kostet einen Euro.
The book costs one euro. (einen = masc. accusative, not ein)
Der Kaffee kostet keinen Cent mehr als gestern.
The coffee costs not a cent more than yesterday. (keinen = masc. accusative)
With feminine, neuter, and plural prices the accusative looks like the nominative, so the case is invisible — but it is still accusative. For the general principle, see the accusative as the case of the direct object and verb government and valency.
The double accusative: kosten + cost in time/effort
Kosten has a second, very German pattern: it can take two accusatives — the person it costs and what it costs them. This is used figuratively for time, energy, nerves, and life:
Das hat mich viel Zeit gekostet.
That cost me a lot of time. (mich = person, viel Zeit = what it cost — both accusative)
Der Umzug kostet uns den letzten Nerv.
The move is costing us our last nerve. (idiomatic; uns + den letzten Nerv, both accusative)
Note that the person here is accusative (mich, uns), not dative — which surprises learners who expect a dative "indirect object" as in geben. With kosten both slots are accusative.
A second meaning: to taste / to sample
The same verb form also means "to taste" in the sense of trying food — sampling a bite to check the flavour. Here it takes a normal accusative object (the food) and uses haben in the Perfekt:
Möchten Sie den Wein einmal kosten?
Would you like to taste the wine? (formal; restaurant/wine-tasting context)
Do not confuse this with schmecken, which means "to taste" in the sense of having a flavour (Das schmeckt gut = "that tastes good"). Kosten = the act of sampling; schmecken = the flavour an item has.
Common idioms and fixed expressions
| Expression | English |
|---|---|
| Was kostet die Welt? | "What does the world cost?" — said when feeling carefree/extravagant. |
| Das kostet mich nur ein Lächeln. | That costs me nothing more than a smile (i.e. it's easy for me). |
| koste es, was es wolle | whatever it takes / cost what it may (literary/emphatic, subjunctive set phrase). |
| Das hat ihn den Job gekostet. | That cost him his job. (double accusative, figurative) |
Wir bringen das zu Ende, koste es, was es wolle.
We'll see this through, whatever it takes. (literary/emphatic fixed phrase using the old Konjunktiv I 'wolle')
Common Mistakes
❌ Das Buch kostet ein Euro.
Incorrect — the price is a direct object, so a masculine noun takes the accusative einen, not the nominative ein.
✅ Das Buch kostet einen Euro.
The book costs one euro.
❌ Wie viel hat es gekost?
Incorrect participle — the -t stem needs the support -e-; the participle is gekostet, never 'gekost'.
✅ Wie viel hat es gekostet?
How much did it cost?
❌ Das ist mir viel Zeit gekostet.
Incorrect case — with kosten the person is accusative (mich), not dative (mir); there is no dative slot here.
✅ Das hat mich viel Zeit gekostet.
That cost me a lot of time.
❌ Der Wein kostet gut.
Wrong verb — to say something has a good flavour you need schmecken; kosten means to sample or to have a price.
✅ Der Wein schmeckt gut.
The wine tastes good.
❌ Das ist teuer gekostet.
Incorrect — kosten is not combined with an adjective like 'teuer'; state the amount, or use 'teuer sein'.
✅ Das hat viel gekostet.
That cost a lot. (or: Das war teuer.)
Key Takeaways
- Principal parts: kosten – kostete – hat gekostet (Perfekt with haben).
- The -t stem forces a support -e-: du kostest, er kostet, kostete, gekostet.
- The price is accusative — einen Euro, keinen Cent — not nominative.
- It can take a double accusative for figurative cost: Das kostet mich viel Zeit (person + thing, both accusative — never dative).
- A second sense is "to taste/sample" (den Wein kosten); for "to have a flavour" use schmecken.
Now practice German
Reading grammar gets you part of the way. The exercises are where it sticks — free, no signup needed.
Start learning German→Related Topics
- Present Tense: Stems Ending in -t, -d, -s, -ß, -zA2 — Two pronunciation-driven adjustments to the present tense — the linking -e- and the disappearing -s of the du-form.
- Präteritum of Weak Verbs (-te)A2 — The fully regular weak past: stem + -te + endings, the ich/er identity, and the linking -ete- after t- and d-stems.
- Past Participles of Weak Verbs (ge-...-t)A2 — How to build the regular German past participle: ge- + stem + -t, plus the verbs that drop ge- entirely.
- The Accusative CaseA1 — The accusative marks the direct object — and because only masculine articles visibly change, masculine 'den/einen' is the system's single biggest stumbling block.
- schmecken: Full Conjugation and UsageA2 — Complete conjugation of schmecken 'to taste (good)' across every tense and mood, with the dative-verb logic (das schmeckt mir), the schmecken nach pattern, and the errors English speakers make.
- zahlen: Full Conjugation and UsageA2 — Complete conjugation of the weak verb zahlen 'to pay' across every tense, with the bezahlen contrast, the zahlen/zählen trap, the prefixed forms einzahlen and auszahlen, restaurant phrases, and the errors English speakers make.