diff --git a/crud.py b/crud.py
index 847da5c..85ba9cc 100644
--- a/crud.py
+++ b/crud.py
@@ -14,8 +14,10 @@ from .models import (
     CreateJournalEntry,
     EntryLine,
     JournalEntry,
+    StoredUserWalletSettings,
     UserBalance,
     UserCastleSettings,
+    UserWalletSettings,
 )
 
 db = Database("ext_castle")
@@ -377,3 +379,33 @@ async def update_castle_settings(
     settings = UserCastleSettings(**data.dict(), id=user_id)
     await db.update("extension_settings", settings)
     return settings
+
+
+# ===== USER WALLET SETTINGS =====
+
+
+async def create_user_wallet_settings(
+    user_id: str, data: UserWalletSettings
+) -> UserWalletSettings:
+    settings = StoredUserWalletSettings(**data.dict(), id=user_id)
+    await db.insert("user_wallet_settings", settings)
+    return settings
+
+
+async def get_user_wallet_settings(user_id: str) -> Optional[UserWalletSettings]:
+    return await db.fetchone(
+        """
+        SELECT * FROM user_wallet_settings
+        WHERE id = :user_id
+        """,
+        {"user_id": user_id},
+        UserWalletSettings,
+    )
+
+
+async def update_user_wallet_settings(
+    user_id: str, data: UserWalletSettings
+) -> UserWalletSettings:
+    settings = StoredUserWalletSettings(**data.dict(), id=user_id)
+    await db.update("user_wallet_settings", settings)
+    return settings
diff --git a/migrations.py b/migrations.py
index 0c8b0ba..2144a8e 100644
--- a/migrations.py
+++ b/migrations.py
@@ -140,3 +140,18 @@ async def m003_extension_settings(db):
         );
         """
     )
+
+
+async def m004_user_wallet_settings(db):
+    """
+    Create user_wallet_settings table for per-user wallet configuration.
+    """
+    await db.execute(
+        f"""
+        CREATE TABLE user_wallet_settings (
+            id TEXT NOT NULL PRIMARY KEY,
+            user_wallet_id TEXT,
+            updated_at TIMESTAMP NOT NULL DEFAULT {db.timestamp_now}
+        );
+        """
+    )
diff --git a/models.py b/models.py
index e54960a..f1aa8e6 100644
--- a/models.py
+++ b/models.py
@@ -119,3 +119,16 @@ class UserCastleSettings(CastleSettings):
     """User-specific settings (stored with user_id)"""
 
     id: str
+
+
+class UserWalletSettings(BaseModel):
+    """Per-user wallet settings"""
+
+    user_wallet_id: Optional[str] = None  # The wallet ID for this specific user
+    updated_at: datetime = Field(default_factory=lambda: datetime.now())
+
+
+class StoredUserWalletSettings(UserWalletSettings):
+    """Stored user wallet settings with user ID"""
+
+    id: str  # user_id
diff --git a/services.py b/services.py
index ff3e5d6..47a3d7b 100644
--- a/services.py
+++ b/services.py
@@ -1,9 +1,12 @@
 from .crud import (
     create_castle_settings,
+    create_user_wallet_settings,
     get_castle_settings,
+    get_user_wallet_settings,
     update_castle_settings,
+    update_user_wallet_settings,
 )
-from .models import CastleSettings
+from .models import CastleSettings, UserWalletSettings
 
 
 async def get_settings(user_id: str) -> CastleSettings:
@@ -21,3 +24,22 @@ async def update_settings(user_id: str, data: CastleSettings) -> CastleSettings:
         settings = await update_castle_settings(user_id, data)
 
     return settings
+
+
+async def get_user_wallet(user_id: str) -> UserWalletSettings:
+    settings = await get_user_wallet_settings(user_id)
+    if not settings:
+        settings = await create_user_wallet_settings(user_id, UserWalletSettings())
+    return settings
+
+
+async def update_user_wallet(
+    user_id: str, data: UserWalletSettings
+) -> UserWalletSettings:
+    settings = await get_user_wallet_settings(user_id)
+    if not settings:
+        settings = await create_user_wallet_settings(user_id, data)
+    else:
+        settings = await update_user_wallet_settings(user_id, data)
+
+    return settings
diff --git a/static/js/index.js b/static/js/index.js
index 407907a..a5eb17e 100644
--- a/static/js/index.js
+++ b/static/js/index.js
@@ -12,9 +12,11 @@ window.app = Vue.createApp({
       accounts: [],
       currencies: [],
       settings: null,
+      userWalletSettings: null,
       isAdmin: false,
       isSuperUser: false,
       castleWalletConfigured: false,
+      userWalletConfigured: false,
       expenseDialog: {
         show: false,
         description: '',
@@ -34,6 +36,11 @@ window.app = Vue.createApp({
         show: false,
         castleWalletId: '',
         loading: false
+      },
+      userWalletDialog: {
+        show: false,
+        userWalletId: '',
+        loading: false
       }
     }
   },
@@ -123,10 +130,27 @@ window.app = Vue.createApp({
         this.castleWalletConfigured = false
       }
     },
+    async loadUserWallet() {
+      try {
+        const response = await LNbits.api.request(
+          'GET',
+          '/castle/api/v1/user/wallet',
+          this.g.user.wallets[0].inkey
+        )
+        this.userWalletSettings = response.data
+        this.userWalletConfigured = !!(this.userWalletSettings && this.userWalletSettings.user_wallet_id)
+      } catch (error) {
+        this.userWalletConfigured = false
+      }
+    },
     showSettingsDialog() {
       this.settingsDialog.castleWalletId = this.settings?.castle_wallet_id || ''
       this.settingsDialog.show = true
     },
+    showUserWalletDialog() {
+      this.userWalletDialog.userWalletId = this.userWalletSettings?.user_wallet_id || ''
+      this.userWalletDialog.show = true
+    },
     async submitSettings() {
       if (!this.settingsDialog.castleWalletId) {
         this.$q.notify({
@@ -158,6 +182,37 @@ window.app = Vue.createApp({
         this.settingsDialog.loading = false
       }
     },
+    async submitUserWallet() {
+      if (!this.userWalletDialog.userWalletId) {
+        this.$q.notify({
+          type: 'warning',
+          message: 'Wallet ID is required'
+        })
+        return
+      }
+
+      this.userWalletDialog.loading = true
+      try {
+        await LNbits.api.request(
+          'PUT',
+          '/castle/api/v1/user/wallet',
+          this.g.user.wallets[0].inkey,
+          {
+            user_wallet_id: this.userWalletDialog.userWalletId
+          }
+        )
+        this.$q.notify({
+          type: 'positive',
+          message: 'Wallet configured successfully'
+        })
+        this.userWalletDialog.show = false
+        await this.loadUserWallet()
+      } catch (error) {
+        LNbits.utils.notifyApiError(error)
+      } finally {
+        this.userWalletDialog.loading = false
+      }
+    },
     async submitExpense() {
       this.expenseDialog.loading = true
       try {
@@ -252,5 +307,6 @@ window.app = Vue.createApp({
     await this.loadAccounts()
     await this.loadCurrencies()
     await this.loadSettings()
+    await this.loadUserWallet()
   }
 })
diff --git a/templates/castle/index.html b/templates/castle/index.html
index 07c0340..a39bdae 100644
--- a/templates/castle/index.html
+++ b/templates/castle/index.html
@@ -16,9 +16,12 @@
             <h5 class="q-my-none">🏰 Castle Accounting</h5>
             <p class="q-mb-none">Track expenses, receivables, and balances for the collective</p>
           </div>
-          <div class="col-auto" v-if="isSuperUser">
-            <q-btn flat round icon="settings" @click="showSettingsDialog">
-              <q-tooltip>Settings (Super User Only)</q-tooltip>
+          <div class="col-auto">
+            <q-btn flat round icon="account_balance_wallet" @click="showUserWalletDialog">
+              <q-tooltip>Configure Your Wallet</q-tooltip>
+            </q-btn>
+            <q-btn v-if="isSuperUser" flat round icon="settings" @click="showSettingsDialog">
+              <q-tooltip>Castle Settings (Super User Only)</q-tooltip>
             </q-btn>
           </div>
         </div>
@@ -47,6 +50,18 @@
       </div>
     </q-banner>
 
+    <q-banner v-if="castleWalletConfigured && !userWalletConfigured" class="bg-orange text-white" rounded>
+      <template v-slot:avatar>
+        <q-icon name="account_balance_wallet" color="white"></q-icon>
+      </template>
+      <div>
+        <strong>Wallet Setup Required:</strong> You must configure your wallet before using this extension.
+      </div>
+      <template v-slot:action>
+        <q-btn flat color="white" label="Configure Wallet" @click="showUserWalletDialog"></q-btn>
+      </template>
+    </q-banner>
+
     <!-- User Balance Card -->
     <q-card>
       <q-card-section>
@@ -91,12 +106,15 @@
           <q-btn
             color="primary"
             @click="expenseDialog.show = true"
-            :disable="!castleWalletConfigured"
+            :disable="!castleWalletConfigured || !userWalletConfigured"
           >
             Add Expense
             <q-tooltip v-if="!castleWalletConfigured">
               Castle wallet must be configured first
             </q-tooltip>
+            <q-tooltip v-if="castleWalletConfigured && !userWalletConfigured">
+              You must configure your wallet first
+            </q-tooltip>
           </q-btn>
           <q-btn color="secondary" @click="loadTransactions">
             View Transactions
@@ -317,4 +335,32 @@
   </q-card>
 </q-dialog>
 
+<!-- User Wallet Dialog -->
+<q-dialog v-model="userWalletDialog.show" position="top">
+  <q-card v-if="userWalletDialog.show" class="q-pa-lg q-pt-xl lnbits__dialog-card">
+    <q-form @submit="submitUserWallet" class="q-gutter-md">
+      <div class="text-h6 q-mb-md">Configure Your Wallet</div>
+
+      <q-input
+        filled
+        dense
+        v-model.trim="userWalletDialog.userWalletId"
+        label="Your Wallet ID *"
+        placeholder="Enter your wallet ID"
+      ></q-input>
+
+      <div class="text-caption text-grey">
+        This is the wallet you'll use for Castle transactions. You can find your wallet ID in the LNbits wallet settings.
+      </div>
+
+      <div class="row q-mt-lg">
+        <q-btn unelevated color="primary" type="submit" :loading="userWalletDialog.loading">
+          Save Wallet
+        </q-btn>
+        <q-btn v-close-popup flat color="grey" class="q-ml-auto">Cancel</q-btn>
+      </div>
+    </q-form>
+  </q-card>
+</q-dialog>
+
 {% endblock %}
diff --git a/views_api.py b/views_api.py
index d2bc6f4..42ed6b7 100644
--- a/views_api.py
+++ b/views_api.py
@@ -36,8 +36,9 @@ from .models import (
     ReceivableEntry,
     RevenueEntry,
     UserBalance,
+    UserWalletSettings,
 )
-from .services import get_settings, update_settings
+from .services import get_settings, get_user_wallet, update_settings, update_user_wallet
 
 castle_api_router = APIRouter()
 
@@ -56,6 +57,17 @@ async def check_castle_wallet_configured() -> str:
     return settings.castle_wallet_id
 
 
+async def check_user_wallet_configured(user_id: str) -> str:
+    """Ensure user has configured their wallet, return wallet_id"""
+    settings = await get_user_wallet(user_id)
+    if not settings or not settings.user_wallet_id:
+        raise HTTPException(
+            status_code=HTTPStatus.BAD_REQUEST,
+            detail="You must configure your wallet in settings before using this feature.",
+        )
+    return settings.user_wallet_id
+
+
 # ===== UTILITY ENDPOINTS =====
 
 
@@ -170,6 +182,11 @@ async def api_create_expense_entry(
 
     If currency is provided, amount is converted from fiat to satoshis.
     """
+    # Check that castle wallet is configured
+    await check_castle_wallet_configured()
+
+    # Check that user has configured their wallet
+    await check_user_wallet_configured(wallet.wallet.user)
     # Handle currency conversion
     amount_sats = int(data.amount)
     metadata = {}
@@ -502,3 +519,32 @@ async def api_update_settings(
         )
     user_id = "admin"
     return await update_settings(user_id, data)
+
+
+# ===== USER WALLET ENDPOINTS =====
+
+
+@castle_api_router.get("/api/v1/user/wallet")
+async def api_get_user_wallet(
+    user: User = Depends(check_user_exists),
+) -> UserWalletSettings:
+    """Get current user's wallet settings"""
+    settings = await get_user_wallet(user.id)
+    # Return empty settings if not configured (so UI can show setup screen)
+    if not settings:
+        return UserWalletSettings()
+    return settings
+
+
+@castle_api_router.put("/api/v1/user/wallet")
+async def api_update_user_wallet(
+    data: UserWalletSettings,
+    user: User = Depends(check_user_exists),
+) -> UserWalletSettings:
+    """Update current user's wallet settings"""
+    if not data.user_wallet_id:
+        raise HTTPException(
+            status_code=HTTPStatus.BAD_REQUEST,
+            detail="User wallet ID is required",
+        )
+    return await update_user_wallet(user.id, data)