diff --git a/libs/sharenet-passport/src/application/use_cases.rs b/libs/sharenet-passport/src/application/use_cases.rs
index 8e15e38..d55da23 100644
--- a/libs/sharenet-passport/src/application/use_cases.rs
+++ b/libs/sharenet-passport/src/application/use_cases.rs
@@ -80,6 +80,7 @@ where
                 &passport.did,
                 &passport.univ_id,
                 &passport.user_profiles,
+                &passport.date_of_birth,
             )
             .map_err(|e| ApplicationError::UseCaseError(format!("Failed to encrypt file: {}", e.into())))?;
 
@@ -169,6 +170,7 @@ where
                 &passport.did,
                 &passport.univ_id,
                 &passport.user_profiles,
+                &passport.date_of_birth,
             )
             .map_err(|e| ApplicationError::UseCaseError(format!("Failed to encrypt file: {}", e.into())))?;
 
@@ -217,7 +219,7 @@ where
             .map_err(|e| ApplicationError::UseCaseError(format!("Failed to load file: {}", e.into())))?;
 
         // Decrypt file
-        let (seed, public_key, private_key, user_profiles) = self
+        let (seed, public_key, private_key, user_profiles, date_of_birth) = self
             .file_encryptor
             .decrypt(&passport_file, password)
             .map_err(|e| ApplicationError::UseCaseError(format!("Failed to decrypt file: {}", e.into())))?;
@@ -231,6 +233,7 @@ where
             passport_file.univ_id.clone(),
         );
         passport.user_profiles = user_profiles;
+        passport.date_of_birth = date_of_birth;
 
         // Re-encrypt and save if output path provided
         if let Some(output_path) = output_path {
@@ -243,6 +246,7 @@ where
                     &passport.did,
                     &passport.univ_id,
                     &passport.user_profiles,
+                    &passport.date_of_birth,
                 )
                 .map_err(|e| ApplicationError::UseCaseError(format!("Failed to re-encrypt file: {}", e.into())))?;
 
@@ -291,6 +295,7 @@ where
                 &passport.did,
                 &passport.univ_id,
                 &passport.user_profiles,
+                &passport.date_of_birth,
             )
             .map_err(|e| ApplicationError::UseCaseError(format!("Failed to encrypt file: {}", e.into())))?;
 
@@ -377,6 +382,7 @@ where
                 &passport.did,
                 &passport.univ_id,
                 &passport.user_profiles,
+                &passport.date_of_birth,
             )
             .map_err(|e| ApplicationError::UseCaseError(format!("Failed to encrypt file: {}", e.into())))?;
 
@@ -451,6 +457,7 @@ where
                 &passport.did,
                 &passport.univ_id,
                 &passport.user_profiles,
+                &passport.date_of_birth,
             )
             .map_err(|e| ApplicationError::UseCaseError(format!("Failed to encrypt file: {}", e.into())))?;
 
@@ -506,6 +513,7 @@ where
                 &passport.did,
                 &passport.univ_id,
                 &passport.user_profiles,
+                &passport.date_of_birth,
             )
             .map_err(|e| ApplicationError::UseCaseError(format!("Failed to encrypt file: {}", e.into())))?;
 
diff --git a/libs/sharenet-passport/src/application/use_cases_test.rs b/libs/sharenet-passport/src/application/use_cases_test.rs
index e85ab24..98afba7 100644
--- a/libs/sharenet-passport/src/application/use_cases_test.rs
+++ b/libs/sharenet-passport/src/application/use_cases_test.rs
@@ -46,6 +46,7 @@ mod tests {
             language: Some("en".to_string()),
             notifications_enabled: true,
             auto_sync: false,
+            show_date_of_birth: false,
         };
 
         let result = create_profile_use_case.execute(
@@ -104,6 +105,7 @@ mod tests {
             language: Some("en".to_string()),
             notifications_enabled: true,
             auto_sync: false,
+            show_date_of_birth: false,
         };
 
         let result1 = create_profile_use_case.execute(
@@ -133,6 +135,7 @@ mod tests {
             language: Some("es".to_string()),
             notifications_enabled: false,
             auto_sync: true,
+            show_date_of_birth: false,
         };
 
         let result2 = create_profile_use_case.execute(
@@ -185,6 +188,7 @@ mod tests {
             language: Some("en".to_string()),
             notifications_enabled: true,
             auto_sync: false,
+            show_date_of_birth: false,
         };
 
         create_profile_use_case.execute(
@@ -223,6 +227,7 @@ mod tests {
             language: Some("es".to_string()),
             notifications_enabled: false,
             auto_sync: true,
+            show_date_of_birth: false,
         };
 
         let result = update_profile_use_case.execute(
@@ -282,6 +287,7 @@ mod tests {
             language: Some("en".to_string()),
             notifications_enabled: true,
             auto_sync: false,
+            show_date_of_birth: false,
         };
 
         let result = update_profile_use_case.execute(
@@ -334,6 +340,7 @@ mod tests {
             language: Some("en".to_string()),
             notifications_enabled: true,
             auto_sync: false,
+            show_date_of_birth: false,
         };
 
         create_profile_use_case.execute(
diff --git a/libs/sharenet-passport/src/domain/entities.rs b/libs/sharenet-passport/src/domain/entities.rs
index 94dd286..8964b64 100644
--- a/libs/sharenet-passport/src/domain/entities.rs
+++ b/libs/sharenet-passport/src/domain/entities.rs
@@ -80,6 +80,7 @@ pub struct Passport {
     pub did: Did,
     pub univ_id: String,
     pub user_profiles: Vec<UserProfile>,
+    pub date_of_birth: Option<DateOfBirth>,
 }
 
 impl Passport {
@@ -108,6 +109,7 @@ impl Passport {
                 language: None,
                 notifications_enabled: true,
                 auto_sync: true,
+                show_date_of_birth: false,
             },
         );
 
@@ -118,6 +120,7 @@ impl Passport {
             did,
             univ_id,
             user_profiles: vec![default_profile],
+            date_of_birth: None,
         }
     }
 
@@ -250,6 +253,14 @@ pub struct UserPreferences {
     pub language: Option<String>,
     pub notifications_enabled: bool,
     pub auto_sync: bool,
+    pub show_date_of_birth: bool,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct DateOfBirth {
+    pub month: u8,
+    pub day: u8,
+    pub year: u16,
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
@@ -298,4 +309,5 @@ pub struct PassportFile {
     pub created_at: u64,
     pub version: String,
     pub enc_user_profiles: Vec<u8>, // Encrypted CBOR of Vec<UserProfile>
+    pub enc_date_of_birth: Vec<u8>, // Encrypted CBOR of Option<DateOfBirth>
 }
\ No newline at end of file
diff --git a/libs/sharenet-passport/src/domain/entities_test.rs b/libs/sharenet-passport/src/domain/entities_test.rs
index f933477..2d20ed2 100644
--- a/libs/sharenet-passport/src/domain/entities_test.rs
+++ b/libs/sharenet-passport/src/domain/entities_test.rs
@@ -75,6 +75,7 @@ mod tests {
             language: Some("en".to_string()),
             notifications_enabled: true,
             auto_sync: false,
+            show_date_of_birth: false,
         };
 
         let profile = UserProfile {
@@ -120,6 +121,7 @@ mod tests {
                 language: None,
                 notifications_enabled: true,
                 auto_sync: true,
+                show_date_of_birth: false,
             },
             created_at: 1234567890,
             updated_at: 1234567890,
@@ -162,6 +164,7 @@ mod tests {
                 language: None,
                 notifications_enabled: false,
                 auto_sync: true,
+                show_date_of_birth: false,
             },
             created_at: 1234567890,
             updated_at: 1234567890,
@@ -195,6 +198,7 @@ mod tests {
                 language: None,
                 notifications_enabled: true,
                 auto_sync: false,
+                show_date_of_birth: false,
             },
             created_at: 1234567890,
             updated_at: 1234567890,
@@ -223,6 +227,7 @@ mod tests {
                 language: None,
                 notifications_enabled: true,
                 auto_sync: false,
+                show_date_of_birth: false,
             },
             created_at: 1234567890,
             updated_at: 1234567890,
diff --git a/libs/sharenet-passport/src/domain/traits.rs b/libs/sharenet-passport/src/domain/traits.rs
index 20d2725..fcc5bb5 100644
--- a/libs/sharenet-passport/src/domain/traits.rs
+++ b/libs/sharenet-passport/src/domain/traits.rs
@@ -26,13 +26,14 @@ pub trait FileEncryptor {
         did: &Did,
         univ_id: &str,
         user_profiles: &[UserProfile],
+        date_of_birth: &Option<DateOfBirth>,
     ) -> Result<PassportFile, Self::Error>;
 
     fn decrypt(
         &self,
         file: &PassportFile,
         password: &str,
-    ) -> Result<(Seed, PublicKey, PrivateKey, Vec<UserProfile>), Self::Error>;
+    ) -> Result<(Seed, PublicKey, PrivateKey, Vec<UserProfile>, Option<DateOfBirth>), Self::Error>;
 }
 
 pub trait FileStorage {
diff --git a/libs/sharenet-passport/src/infrastructure/crypto/native.rs b/libs/sharenet-passport/src/infrastructure/crypto/native.rs
index 6a607d0..1411b3d 100644
--- a/libs/sharenet-passport/src/infrastructure/crypto/native.rs
+++ b/libs/sharenet-passport/src/infrastructure/crypto/native.rs
@@ -90,6 +90,7 @@ impl FileEncryptor for XChaCha20FileEncryptor {
         did: &Did,
         univ_id: &str,
         user_profiles: &[UserProfile],
+        date_of_birth: &Option<DateOfBirth>,
     ) -> Result<PassportFile, Self::Error> {
         // Generate salt and nonce
         let mut salt = [0u8; SALT_LENGTH];
@@ -118,6 +119,13 @@ impl FileEncryptor for XChaCha20FileEncryptor {
             .encrypt(&nonce, &*user_profiles_bytes)
             .map_err(|e| DomainError::CryptographicError(format!("User profiles encryption failed: {}", e)))?;
 
+        // Serialize and encrypt date of birth
+        let date_of_birth_bytes = serde_cbor::to_vec(&date_of_birth)
+            .map_err(|e| DomainError::CryptographicError(format!("Failed to serialize date of birth: {}", e)))?;
+        let enc_date_of_birth = cipher
+            .encrypt(&nonce, &*date_of_birth_bytes)
+            .map_err(|e| DomainError::CryptographicError(format!("Date of birth encryption failed: {}", e)))?;
+
         // Get current timestamp
         let created_at = SystemTime::now()
             .duration_since(UNIX_EPOCH)
@@ -136,6 +144,7 @@ impl FileEncryptor for XChaCha20FileEncryptor {
             created_at,
             version: "1.0.0".to_string(),
             enc_user_profiles,
+            enc_date_of_birth,
         })
     }
 
@@ -143,7 +152,7 @@ impl FileEncryptor for XChaCha20FileEncryptor {
         &self,
         file: &PassportFile,
         password: &str,
-    ) -> Result<(Seed, PublicKey, PrivateKey, Vec<UserProfile>), Self::Error> {
+    ) -> Result<(Seed, PublicKey, PrivateKey, Vec<UserProfile>, Option<DateOfBirth>), Self::Error> {
         // Validate file format
         validate_file_format(&file.kdf, &file.cipher)?;
 
@@ -180,7 +189,14 @@ impl FileEncryptor for XChaCha20FileEncryptor {
         let user_profiles: Vec<UserProfile> = serde_cbor::from_slice(&user_profiles_bytes)
             .map_err(|e| DomainError::CryptographicError(format!("Failed to deserialize user profiles: {}", e)))?;
 
+        // Decrypt date of birth
+        let date_of_birth_bytes = cipher
+            .decrypt(&nonce, &*file.enc_date_of_birth)
+            .map_err(|e| DomainError::CryptographicError(format!("Date of birth decryption failed: {}", e)))?;
+        let date_of_birth: Option<DateOfBirth> = serde_cbor::from_slice(&date_of_birth_bytes)
+            .map_err(|e| DomainError::CryptographicError(format!("Failed to deserialize date of birth: {}", e)))?;
+
         // Note: univ_id is stored in the PassportFile and will be used when creating the Passport
-        Ok((seed, public_key, private_key, user_profiles))
+        Ok((seed, public_key, private_key, user_profiles, date_of_birth))
     }
 }
\ No newline at end of file
diff --git a/libs/sharenet-passport/src/infrastructure/crypto/native_test.rs b/libs/sharenet-passport/src/infrastructure/crypto/native_test.rs
index 1df46d0..043d57c 100644
--- a/libs/sharenet-passport/src/infrastructure/crypto/native_test.rs
+++ b/libs/sharenet-passport/src/infrastructure/crypto/native_test.rs
@@ -45,7 +45,7 @@ mod tests {
         let password = "test-password";
 
         // Encrypt
-        let encrypted_file = encryptor.encrypt(&seed, password, &public_key, &did, "u:Test Universe:12345678-1234-1234-1234-123456789012", &[]).unwrap();
+        let encrypted_file = encryptor.encrypt(&seed, password, &public_key, &did, "u:Test Universe:12345678-1234-1234-1234-123456789012", &[], &None).unwrap();
 
         // Verify file structure
         assert_eq!(encrypted_file.kdf, "HKDF-SHA256");
@@ -56,7 +56,7 @@ mod tests {
         assert_eq!(encrypted_file.did, did.0);
 
         // Decrypt
-        let (decrypted_seed, decrypted_public_key, _, _) = encryptor.decrypt(&encrypted_file, password).unwrap();
+        let (decrypted_seed, decrypted_public_key, _, _, _) = encryptor.decrypt(&encrypted_file, password).unwrap();
 
         // Verify decryption
         assert_eq!(decrypted_seed.as_bytes(), seed.as_bytes());
@@ -72,7 +72,7 @@ mod tests {
         let did = Did::new(&public_key);
 
         // Encrypt with one password
-        let encrypted_file = encryptor.encrypt(&seed, "correct-password", &public_key, &did, "u:Test Universe:12345678-1234-1234-1234-123456789012", &[]).unwrap();
+        let encrypted_file = encryptor.encrypt(&seed, "correct-password", &public_key, &did, "u:Test Universe:12345678-1234-1234-1234-123456789012", &[], &None).unwrap();
 
         // Try to decrypt with wrong password
         let result = encryptor.decrypt(&encrypted_file, "wrong-password");
diff --git a/libs/sharenet-passport/src/infrastructure/crypto/wasm.rs b/libs/sharenet-passport/src/infrastructure/crypto/wasm.rs
index 3367ba8..980fa54 100644
--- a/libs/sharenet-passport/src/infrastructure/crypto/wasm.rs
+++ b/libs/sharenet-passport/src/infrastructure/crypto/wasm.rs
@@ -91,6 +91,7 @@ impl FileEncryptor for XChaCha20FileEncryptor {
         did: &Did,
         univ_id: &str,
         user_profiles: &[UserProfile],
+        date_of_birth: &Option<DateOfBirth>,
     ) -> Result<PassportFile, Self::Error> {
         // Generate salt and nonce using WASM-compatible RNG
         let mut salt = [0u8; SALT_LENGTH];
@@ -120,6 +121,13 @@ impl FileEncryptor for XChaCha20FileEncryptor {
             .encrypt(&nonce, &*user_profiles_bytes)
             .map_err(|e| DomainError::CryptographicError(format!("User profiles encryption failed: {}", e)))?;
 
+        // Serialize and encrypt date of birth
+        let date_of_birth_bytes = serde_cbor::to_vec(&date_of_birth)
+            .map_err(|e| DomainError::CryptographicError(format!("Failed to serialize date of birth: {}", e)))?;
+        let enc_date_of_birth = cipher
+            .encrypt(&nonce, &*date_of_birth_bytes)
+            .map_err(|e| DomainError::CryptographicError(format!("Date of birth encryption failed: {}", e)))?;
+
         // Get current timestamp using WASM-compatible time
         let created_at = time::now_seconds()?;
 
@@ -135,6 +143,7 @@ impl FileEncryptor for XChaCha20FileEncryptor {
             created_at,
             version: "1.0.0".to_string(),
             enc_user_profiles,
+            enc_date_of_birth,
         })
     }
 
@@ -142,7 +151,7 @@ impl FileEncryptor for XChaCha20FileEncryptor {
         &self,
         file: &PassportFile,
         password: &str,
-    ) -> Result<(Seed, PublicKey, PrivateKey, Vec<UserProfile>), Self::Error> {
+    ) -> Result<(Seed, PublicKey, PrivateKey, Vec<UserProfile>, Option<DateOfBirth>), Self::Error> {
         // Validate file format
         validate_file_format(&file.kdf, &file.cipher)?;
 
@@ -179,7 +188,14 @@ impl FileEncryptor for XChaCha20FileEncryptor {
         let user_profiles: Vec<UserProfile> = serde_cbor::from_slice(&user_profiles_bytes)
             .map_err(|e| DomainError::CryptographicError(format!("Failed to deserialize user profiles: {}", e)))?;
 
+        // Decrypt date of birth
+        let date_of_birth_bytes = cipher
+            .decrypt(&nonce, &*file.enc_date_of_birth)
+            .map_err(|e| DomainError::CryptographicError(format!("Date of birth decryption failed: {}", e)))?;
+        let date_of_birth: Option<DateOfBirth> = serde_cbor::from_slice(&date_of_birth_bytes)
+            .map_err(|e| DomainError::CryptographicError(format!("Failed to deserialize date of birth: {}", e)))?;
+
         // Note: univ_id is stored in the PassportFile and will be used when creating the Passport
-        Ok((seed, public_key, private_key, user_profiles))
+        Ok((seed, public_key, private_key, user_profiles, date_of_birth))
     }
 }
\ No newline at end of file
diff --git a/libs/sharenet-passport/src/infrastructure/storage/native_test.rs b/libs/sharenet-passport/src/infrastructure/storage/native_test.rs
index 4b4168a..45aaf72 100644
--- a/libs/sharenet-passport/src/infrastructure/storage/native_test.rs
+++ b/libs/sharenet-passport/src/infrastructure/storage/native_test.rs
@@ -25,6 +25,7 @@ mod tests {
             created_at: 1234567890,
             version: "1.0.0".to_string(),
             enc_user_profiles: vec![],
+            enc_date_of_birth: vec![],
         };
 
         // Save the file
diff --git a/libs/sharenet-passport/src/wasm.rs b/libs/sharenet-passport/src/wasm.rs
index f51d8c5..350694c 100644
--- a/libs/sharenet-passport/src/wasm.rs
+++ b/libs/sharenet-passport/src/wasm.rs
@@ -114,7 +114,7 @@ pub fn import_from_encrypted_data(
 
     // Decrypt the passport file using the password
     let encryptor = XChaCha20FileEncryptor;
-    let (seed, public_key, private_key, user_profiles) = encryptor.decrypt(
+    let (seed, public_key, private_key, user_profiles, date_of_birth) = encryptor.decrypt(
         &passport_file,
         &password,
     ).map_err(|e| JsValue::from_str(&format!("Failed to decrypt passport: {}", e)))?;
@@ -128,6 +128,7 @@ pub fn import_from_encrypted_data(
         did,
         univ_id: passport_file.univ_id,
         user_profiles,
+        date_of_birth,
     };
 
     let result = serde_wasm_bindgen::to_value(&passport)
@@ -155,6 +156,7 @@ pub fn export_to_encrypted_data(
         &passport.did,
         &passport.univ_id,
         &passport.user_profiles,
+        &passport.date_of_birth,
     ).map_err(|e| JsValue::from_str(&format!("Failed to encrypt passport: {}", e)))?;
 
     // Serialize to bytes for browser download
diff --git a/sharenet-passport-cli/src/cli/interface.rs b/sharenet-passport-cli/src/cli/interface.rs
index 0fd3753..eb37640 100644
--- a/sharenet-passport-cli/src/cli/interface.rs
+++ b/sharenet-passport-cli/src/cli/interface.rs
@@ -285,6 +285,7 @@ impl CliInterface {
             language,
             notifications_enabled: notifications,
             auto_sync,
+            show_date_of_birth: false,
         };
 
         let create_use_case = CreateUserProfileUseCase::new(
@@ -357,6 +358,7 @@ impl CliInterface {
             language: language.or_else(|| existing_profile.preferences.language.clone()),
             notifications_enabled: notifications.unwrap_or(existing_profile.preferences.notifications_enabled),
             auto_sync: auto_sync.unwrap_or(existing_profile.preferences.auto_sync),
+            show_date_of_birth: existing_profile.preferences.show_date_of_birth,
         };
 
         // Clone values before using them in multiple places