German Possessive Adjectives by Case: Mein, Dein, Sein, Ihr - Complete Guide

Possessive adjectives — my, your, his, her, our, their — are mein, dein, sein, ihr, unser, euer, and formal Ihr in German. The good news: they decline exactly like ein/eine/ein. If you already know that chart, you already know this one too.

Mein Bruder schläft. (My brother sleeps — nominative masculine)
Ich sehe meinen Bruder. (I see my brother — accusative masculine)

All German Possessive Adjectives

Note on "ihr":

• Lowercase ihr = "her" or "their" (context tells you which)
• Uppercase Ihr = formal "your" (goes with "Sie")

Complete Mein/Meine/Mein Chart by Case

Masculine (mein Mann)

Feminine (meine Frau)

Neuter (mein Kind)

Plural (meine Kinder)

Possessive Adjectives Follow Ein's Pattern

Key: if you know ein/eine/ein, you already know every possessive.

How the Other Possessives Decline

Same pattern, different stems — nominative and dative shown here as the two poles (see the mein chart above for the full four-case picture):

Dein (Your — Informal Singular)

Sein (His / Its)

Ihr (Her / Their)

Unser (Our)

Euer (Your — Plural Informal)

Note: "euer" drops its second "e" whenever an ending is added — eu(e)re, eu(e)rem, eu(e)ren.

Ihr (Your — Formal)

Using Possessives in Sentences

Nominative (Subject)

• Mein Vater ist Arzt. (My father is a doctor.)
• Dein Bruder spielt Fußball. (Your brother plays soccer.)
• Sein Auto ist schnell. (His car is fast.)
• Ihre Mutter arbeitet. (Her mother works.)
• Unsere Schule ist groß. (Our school is big.)
• Euer Lehrer ist nett. (Your teacher is nice — plural informal.)

Accusative (Direct Object)

• Ich sehe meinen Sohn. (I see my son.)
• Wir besuchen deinen Onkel. (We visit your uncle.)
• Sie mag seinen Freund. (She likes his friend.)
• Ich kenne ihren Cousin. (I know her cousin.)
• Wir helfen unserem Großvater. (We help our grandfather.)

Dative (Indirect Object)

• Ich gebe meinem Bruder ein Geschenk. (I give my brother a gift.)
• Sie schreibt deiner Schwester eine Email. (She writes your sister an email.)
• Wir helfen unserem Freund. (We help our friend.)
• Ich danke eurer Familie. (I thank your family — plural.)

Genitive (Possession)

• Das Auto meines Vaters ist rot. (My father's car is red.)
• Die Freunde deiner Schwester sind nett. (Your sister's friends are nice.)
• Das Haus seines Onkels ist groß. (His uncle's house is big.)
• Die Farbe ihrer Augen ist blau. (The color of her eyes is blue.)

Formal "Sie" vs. Informal "Du / Ihr"

Key: formal Ihr is always capitalized. Informal plural euer is always lowercase.

Possessives with Adjectives

Add an adjective and its ending follows the possessive's own case and gender — same rule as after ein:

Full sentences:

• Mein großer Bruder schläft. (My big brother sleeps.)
• Ich sehe meinen großen Bruder. (I see my big brother.)
• Ich helfe meinem großen Bruder. (I help my big brother.)

See the full adjective endings guide for every combination.

Common Mistakes with Possessives

Mistake 1: Forgetting Case Changes

Wrong: Mein Mann sieht mein Frau. (using nominative)
Right: Mein Mann sieht meine Frau. (accusative feminine)

Mistake 2: Confusing Sein (His) and Sein (To Be)

Sein Bruder = his brother (possessive) — Sein Bruder ist alt. = his brother is old. Context makes it clear, but they're two different words that happen to look alike.

Mistake 3: Not Changing in Dative

Wrong: Ich helfe mein Mann. (using nominative)
Right: Ich helfe meinem Mann. (dative)

Mistake 4: Forgetting the Plural Dative -n

Wrong: Ich helfe meine Kinder. (missing the dative -n marker on the noun)
Right: Ich helfe meinen Kindern. (dative plural needs -n)

Mistake 5: Capitalizing Informal "dein" or "euer"

Wrong: Dein Bruder ist nett, wenn du mit einem Freund sprichst. (capitalized mid-sentence)
Right: dein Bruder ist nett — lowercase, unless it's the formal "Ihr."

Practice Exercises

Fill in the correct possessive adjective:

1. Das ist _____ Buch. (This is my book — nominative neuter) — Answer: mein
2. Ich sehe _____ Freundin. (I see your friend — accusative feminine) — Answer: deine
3. Ich helfe _____ Eltern. (I help his parents — dative plural) — Answer: seinen
4. Das Haus _____ Tante ist groß. (My aunt's house is big — genitive feminine) — Answer: meiner
5. Sie gibt _____ Sohn ein Spielzeug. (She gives her son a toy — dative masculine) — Answer: ihrem
6. Wir besuchen _____ Großmutter. (We visit our grandmother — accusative feminine) — Answer: unsere
7. Die Farbe _____ Autos ist blau. (Your car's color is blue — genitive neuter) — Answer: eures
8. Ich danke _____ Lehrer. (I thank your teacher [formal] — dative masculine) — Answer: Ihrem

Quick Reference: All Possessives (Nominative)

Summary: Possessive Adjectives = Ein Endings

Once you've mastered ein/eine/ein across the cases, possessives are automatic:

• Same nominative pattern as ein (mein, deine, sein, etc.)
• Same accusative pattern as ein (masculine changes, others stay)
• Same dative pattern as ein (every gender changes)
• Same genitive pattern as ein (every gender changes, plus noun endings)

The only real difference is the stem you attach the endings to — the endings themselves never change.

FAQ

Do possessives always follow ein's pattern?
Yes, exactly. Mein, dein, sein, and the rest all decline like ein/eine/ein.

Is "Ihr" (formal) capitalized in every case?
Yes, always — German capitalizes every form of the formal "Sie" family, including "Ihr."

Why does German need both dative and accusative?
To distinguish who receives an action directly (accusative) from who receives it indirectly (dative) — the same distinction covered in our case comparison guide.

Can I use a possessive without a noun?
Not directly — you'd switch to a possessive pronoun instead: "Das ist meins" (That is mine), not "Das ist mein."

How do I know when to use formal "Ihr" vs. informal "dein/euer"?
Use "Ihr" for anyone you'd address as "Sie" — strangers, bosses, elders in formal settings. Use "dein/euer" for friends, family, and people your own age you know well.

Related Grammar

Possessives are the last piece of the article-declension puzzle — see der/die/das by case, ein/eine/ein by case, and adjective endings, or step back to the full case comparison.

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