diff --git a/app/api/v1/admin/letzshop.py b/app/api/v1/admin/letzshop.py
index b12c91d5..b6a1488c 100644
--- a/app/api/v1/admin/letzshop.py
+++ b/app/api/v1/admin/letzshop.py
@@ -22,10 +22,12 @@ from app.services.letzshop import (
     LetzshopClientError,
     LetzshopCredentialsService,
     LetzshopOrderService,
+    OrderNotFoundError,
     VendorNotFoundError,
 )
 from models.database.user import User
 from models.schema.letzshop import (
+    FulfillmentOperationResponse,
     LetzshopConnectionTestRequest,
     LetzshopConnectionTestResponse,
     LetzshopCredentialsCreate,
@@ -647,3 +649,246 @@ def get_import_summary(
         "success": True,
         "summary": summary,
     }
+
+
+# ============================================================================
+# Fulfillment Operations (Admin)
+# ============================================================================
+
+
+@router.post(
+    "/vendors/{vendor_id}/orders/{order_id}/confirm",
+    response_model=FulfillmentOperationResponse,
+)
+def confirm_order(
+    vendor_id: int = Path(..., description="Vendor ID"),
+    order_id: int = Path(..., description="Order ID"),
+    db: Session = Depends(get_db),
+    current_admin: User = Depends(get_current_admin_api),
+):
+    """
+    Confirm all inventory units for a Letzshop order.
+
+    Sends confirmInventoryUnits mutation with isAvailable=true for all items.
+    """
+    order_service = get_order_service(db)
+    creds_service = get_credentials_service(db)
+
+    try:
+        order = order_service.get_order_or_raise(vendor_id, order_id)
+    except OrderNotFoundError:
+        raise ResourceNotFoundException("LetzshopOrder", str(order_id))
+
+    # Get inventory unit IDs from order
+    if not order.inventory_units:
+        return FulfillmentOperationResponse(
+            success=False,
+            message="No inventory units found in order",
+        )
+
+    inventory_unit_ids = [u.get("id") for u in order.inventory_units if u.get("id")]
+
+    if not inventory_unit_ids:
+        return FulfillmentOperationResponse(
+            success=False,
+            message="No inventory unit IDs found in order",
+        )
+
+    try:
+        with creds_service.create_client(vendor_id) as client:
+            result = client.confirm_inventory_units(inventory_unit_ids)
+
+            if not result.get("inventoryUnits"):
+                error_messages = [
+                    e.get("message", "Unknown error")
+                    for e in result.get("errors", [])
+                ]
+                return FulfillmentOperationResponse(
+                    success=False,
+                    message="Some inventory units could not be confirmed",
+                    errors=error_messages,
+                )
+
+            # Update order status
+            order_service.mark_order_confirmed(order)
+            db.commit()
+
+            return FulfillmentOperationResponse(
+                success=True,
+                message=f"Confirmed {len(inventory_unit_ids)} inventory units",
+                confirmed_units=[u.get("id") for u in result.get("inventoryUnits", [])],
+            )
+
+    except LetzshopClientError as e:
+        return FulfillmentOperationResponse(success=False, message=str(e))
+
+
+@router.post(
+    "/vendors/{vendor_id}/orders/{order_id}/reject",
+    response_model=FulfillmentOperationResponse,
+)
+def reject_order(
+    vendor_id: int = Path(..., description="Vendor ID"),
+    order_id: int = Path(..., description="Order ID"),
+    db: Session = Depends(get_db),
+    current_admin: User = Depends(get_current_admin_api),
+):
+    """
+    Decline all inventory units for a Letzshop order.
+
+    Sends confirmInventoryUnits mutation with isAvailable=false for all items.
+    """
+    order_service = get_order_service(db)
+    creds_service = get_credentials_service(db)
+
+    try:
+        order = order_service.get_order_or_raise(vendor_id, order_id)
+    except OrderNotFoundError:
+        raise ResourceNotFoundException("LetzshopOrder", str(order_id))
+
+    # Get inventory unit IDs from order
+    if not order.inventory_units:
+        return FulfillmentOperationResponse(
+            success=False,
+            message="No inventory units found in order",
+        )
+
+    inventory_unit_ids = [u.get("id") for u in order.inventory_units if u.get("id")]
+
+    if not inventory_unit_ids:
+        return FulfillmentOperationResponse(
+            success=False,
+            message="No inventory unit IDs found in order",
+        )
+
+    try:
+        with creds_service.create_client(vendor_id) as client:
+            result = client.reject_inventory_units(inventory_unit_ids)
+
+            if not result.get("inventoryUnits"):
+                error_messages = [
+                    e.get("message", "Unknown error")
+                    for e in result.get("errors", [])
+                ]
+                return FulfillmentOperationResponse(
+                    success=False,
+                    message="Some inventory units could not be declined",
+                    errors=error_messages,
+                )
+
+            # Update order status
+            order_service.mark_order_rejected(order)
+            db.commit()
+
+            return FulfillmentOperationResponse(
+                success=True,
+                message=f"Declined {len(inventory_unit_ids)} inventory units",
+            )
+
+    except LetzshopClientError as e:
+        return FulfillmentOperationResponse(success=False, message=str(e))
+
+
+@router.post(
+    "/vendors/{vendor_id}/orders/{order_id}/items/{item_id}/confirm",
+    response_model=FulfillmentOperationResponse,
+)
+def confirm_single_item(
+    vendor_id: int = Path(..., description="Vendor ID"),
+    order_id: int = Path(..., description="Order ID"),
+    item_id: str = Path(..., description="Inventory Unit ID"),
+    db: Session = Depends(get_db),
+    current_admin: User = Depends(get_current_admin_api),
+):
+    """
+    Confirm a single inventory unit in an order.
+
+    Sends confirmInventoryUnits mutation with isAvailable=true for one item.
+    """
+    order_service = get_order_service(db)
+    creds_service = get_credentials_service(db)
+
+    try:
+        order = order_service.get_order_or_raise(vendor_id, order_id)
+    except OrderNotFoundError:
+        raise ResourceNotFoundException("LetzshopOrder", str(order_id))
+
+    try:
+        with creds_service.create_client(vendor_id) as client:
+            result = client.confirm_inventory_units([item_id])
+
+            if not result.get("inventoryUnits"):
+                error_messages = [
+                    e.get("message", "Unknown error")
+                    for e in result.get("errors", [])
+                ]
+                return FulfillmentOperationResponse(
+                    success=False,
+                    message="Failed to confirm item",
+                    errors=error_messages,
+                )
+
+            # Update local inventory unit state
+            order_service.update_inventory_unit_state(order, item_id, "confirmed_available")
+            db.commit()
+
+            return FulfillmentOperationResponse(
+                success=True,
+                message="Item confirmed",
+                confirmed_units=[item_id],
+            )
+
+    except LetzshopClientError as e:
+        return FulfillmentOperationResponse(success=False, message=str(e))
+
+
+@router.post(
+    "/vendors/{vendor_id}/orders/{order_id}/items/{item_id}/decline",
+    response_model=FulfillmentOperationResponse,
+)
+def decline_single_item(
+    vendor_id: int = Path(..., description="Vendor ID"),
+    order_id: int = Path(..., description="Order ID"),
+    item_id: str = Path(..., description="Inventory Unit ID"),
+    db: Session = Depends(get_db),
+    current_admin: User = Depends(get_current_admin_api),
+):
+    """
+    Decline a single inventory unit in an order.
+
+    Sends confirmInventoryUnits mutation with isAvailable=false for one item.
+    """
+    order_service = get_order_service(db)
+    creds_service = get_credentials_service(db)
+
+    try:
+        order = order_service.get_order_or_raise(vendor_id, order_id)
+    except OrderNotFoundError:
+        raise ResourceNotFoundException("LetzshopOrder", str(order_id))
+
+    try:
+        with creds_service.create_client(vendor_id) as client:
+            result = client.reject_inventory_units([item_id])
+
+            if not result.get("inventoryUnits"):
+                error_messages = [
+                    e.get("message", "Unknown error")
+                    for e in result.get("errors", [])
+                ]
+                return FulfillmentOperationResponse(
+                    success=False,
+                    message="Failed to decline item",
+                    errors=error_messages,
+                )
+
+            # Update local inventory unit state
+            order_service.update_inventory_unit_state(order, item_id, "confirmed_unavailable")
+            db.commit()
+
+            return FulfillmentOperationResponse(
+                success=True,
+                message="Item declined",
+            )
+
+    except LetzshopClientError as e:
+        return FulfillmentOperationResponse(success=False, message=str(e))
diff --git a/app/services/letzshop/order_service.py b/app/services/letzshop/order_service.py
index 781176be..486a0272 100644
--- a/app/services/letzshop/order_service.py
+++ b/app/services/letzshop/order_service.py
@@ -403,6 +403,56 @@ class LetzshopOrderService:
         order.sync_status = "rejected"
         return order
 
+    def update_inventory_unit_state(
+        self, order: LetzshopOrder, item_id: str, state: str
+    ) -> LetzshopOrder:
+        """
+        Update the state of a single inventory unit in an order.
+
+        Args:
+            order: The order containing the inventory unit.
+            item_id: The inventory unit ID to update.
+            state: The new state (confirmed_available, confirmed_unavailable).
+
+        Returns:
+            The updated order.
+        """
+        if not order.inventory_units:
+            return order
+
+        # Update the specific item's state
+        updated_units = []
+        for unit in order.inventory_units:
+            if unit.get("id") == item_id:
+                unit["state"] = state
+            updated_units.append(unit)
+
+        order.inventory_units = updated_units
+
+        # Check if all items are now processed and update order status accordingly
+        all_confirmed = all(
+            u.get("state") in ("confirmed_available", "confirmed_unavailable", "returned")
+            for u in updated_units
+        )
+
+        if all_confirmed:
+            # Determine order status based on item states
+            has_available = any(
+                u.get("state") == "confirmed_available" for u in updated_units
+            )
+            all_unavailable = all(
+                u.get("state") == "confirmed_unavailable" for u in updated_units
+            )
+
+            if all_unavailable:
+                order.sync_status = "rejected"
+                order.rejected_at = datetime.now(UTC)
+            elif has_available:
+                order.sync_status = "confirmed"
+                order.confirmed_at = datetime.now(UTC)
+
+        return order
+
     def set_order_tracking(
         self,
         order: LetzshopOrder,
diff --git a/app/templates/admin/marketplace-letzshop.html b/app/templates/admin/marketplace-letzshop.html
index ea5c1597..d695fb4f 100644
--- a/app/templates/admin/marketplace-letzshop.html
+++ b/app/templates/admin/marketplace-letzshop.html
@@ -274,7 +274,7 @@
                             'bg-red-100 text-red-700': selectedOrder?.sync_status === 'rejected',
                             'bg-blue-100 text-blue-700': selectedOrder?.sync_status === 'shipped'
                         }"
-                        x-text="selectedOrder?.sync_status?.toUpperCase()"
+                        x-text="selectedOrder?.sync_status === 'rejected' ? 'DECLINED' : selectedOrder?.sync_status?.toUpperCase()"
                     ></span>
                 </div>
                 <div>
@@ -296,19 +296,79 @@
             </div>
 
             <div x-show="selectedOrder?.inventory_units?.length > 0">
-                <h4 class="font-medium text-gray-700 dark:text-gray-300 mb-2">Items</h4>
-                <div class="bg-gray-50 dark:bg-gray-700 rounded-lg p-3">
-                    <template x-for="unit in selectedOrder?.inventory_units || []" :key="unit.id">
-                        <div class="flex justify-between text-sm py-1 border-b border-gray-200 dark:border-gray-600 last:border-0">
-                            <span class="text-gray-600 dark:text-gray-400" x-text="unit.id"></span>
-                            <span
-                                class="px-2 py-0.5 text-xs rounded-full"
-                                :class="unit.state === 'confirmed' ? 'bg-green-100 text-green-700' : 'bg-orange-100 text-orange-700'"
-                                x-text="unit.state"
-                            ></span>
+                <h4 class="font-medium text-gray-700 dark:text-gray-300 mb-2">
+                    Items
+                    <span class="text-xs font-normal text-gray-500">
+                        (Each item must be confirmed or declined individually)
+                    </span>
+                </h4>
+                <div class="space-y-2">
+                    <template x-for="(unit, index) in selectedOrder?.inventory_units || []" :key="unit.id">
+                        <div class="bg-gray-50 dark:bg-gray-700 rounded-lg p-3">
+                            <div class="flex justify-between items-start">
+                                <div class="flex-1">
+                                    <p class="font-medium text-gray-700 dark:text-gray-200 text-sm" x-text="unit.product_name || 'Unknown Product'"></p>
+                                    <div class="text-xs text-gray-500 dark:text-gray-400 mt-1 space-y-0.5">
+                                        <p x-show="unit.ean">
+                                            <span class="font-medium">EAN:</span> <span x-text="unit.ean"></span>
+                                            <span x-show="unit.ean_type" class="text-gray-400" x-text="'(' + unit.ean_type + ')'"></span>
+                                        </p>
+                                        <p x-show="unit.sku"><span class="font-medium">SKU:</span> <span x-text="unit.sku"></span></p>
+                                        <p x-show="unit.mpn"><span class="font-medium">MPN:</span> <span x-text="unit.mpn"></span></p>
+                                        <p x-show="unit.price"><span class="font-medium">Price:</span> <span x-text="unit.price + ' EUR'"></span></p>
+                                    </div>
+                                </div>
+                                <div class="flex items-center gap-2 ml-4">
+                                    <!-- Item State Badge -->
+                                    <span
+                                        class="px-2 py-0.5 text-xs rounded-full whitespace-nowrap"
+                                        :class="{
+                                            'bg-orange-100 text-orange-700': unit.state === 'unconfirmed',
+                                            'bg-green-100 text-green-700': unit.state === 'confirmed_available' || unit.state === 'confirmed',
+                                            'bg-red-100 text-red-700': unit.state === 'confirmed_unavailable',
+                                            'bg-gray-100 text-gray-700': unit.state === 'returned'
+                                        }"
+                                        x-text="unit.state === 'confirmed_unavailable' ? 'DECLINED' : (unit.state === 'confirmed_available' ? 'CONFIRMED' : unit.state?.toUpperCase())"
+                                    ></span>
+                                    <!-- Item Actions (only for unconfirmed items) -->
+                                    <template x-if="unit.state === 'unconfirmed' && selectedOrder?.sync_status === 'pending'">
+                                        <div class="flex gap-1">
+                                            <button
+                                                @click="confirmInventoryUnit(selectedOrder, unit, index)"
+                                                class="p-1 text-green-600 hover:bg-green-100 rounded"
+                                                title="Confirm this item"
+                                            >
+                                                <span x-html="$icon('check', 'w-4 h-4')"></span>
+                                            </button>
+                                            <button
+                                                @click="declineInventoryUnit(selectedOrder, unit, index)"
+                                                class="p-1 text-red-600 hover:bg-red-100 rounded"
+                                                title="Decline this item"
+                                            >
+                                                <span x-html="$icon('x', 'w-4 h-4')"></span>
+                                            </button>
+                                        </div>
+                                    </template>
+                                </div>
+                            </div>
                         </div>
                     </template>
                 </div>
+                <!-- Bulk Actions -->
+                <div x-show="selectedOrder?.sync_status === 'pending'" class="mt-4 flex gap-2 justify-end">
+                    <button
+                        @click="confirmAllItems(selectedOrder)"
+                        class="px-3 py-1.5 text-sm text-white bg-green-600 hover:bg-green-700 rounded-lg"
+                    >
+                        Confirm All Items
+                    </button>
+                    <button
+                        @click="declineAllItems(selectedOrder)"
+                        class="px-3 py-1.5 text-sm text-white bg-red-600 hover:bg-red-700 rounded-lg"
+                    >
+                        Decline All Items
+                    </button>
+                </div>
             </div>
         </div>
     </div>
diff --git a/static/admin/js/marketplace-letzshop.js b/static/admin/js/marketplace-letzshop.js
index 58eea747..190020b0 100644
--- a/static/admin/js/marketplace-letzshop.js
+++ b/static/admin/js/marketplace-letzshop.js
@@ -579,6 +579,90 @@ function adminMarketplaceLetzshop() {
             this.showOrderModal = true;
         },
 
+        /**
+         * Confirm a single inventory unit
+         */
+        async confirmInventoryUnit(order, unit, index) {
+            if (!this.selectedVendor) return;
+
+            try {
+                await apiClient.post(
+                    `/admin/letzshop/vendors/${this.selectedVendor.id}/orders/${order.id}/items/${unit.id}/confirm`
+                );
+                // Update local state
+                this.selectedOrder.inventory_units[index].state = 'confirmed_available';
+                this.successMessage = 'Item confirmed';
+                // Reload orders to get updated status
+                await this.loadOrders();
+            } catch (error) {
+                marketplaceLetzshopLog.error('Failed to confirm item:', error);
+                this.error = error.message || 'Failed to confirm item';
+            }
+        },
+
+        /**
+         * Decline a single inventory unit
+         */
+        async declineInventoryUnit(order, unit, index) {
+            if (!this.selectedVendor) return;
+
+            try {
+                await apiClient.post(
+                    `/admin/letzshop/vendors/${this.selectedVendor.id}/orders/${order.id}/items/${unit.id}/decline`
+                );
+                // Update local state
+                this.selectedOrder.inventory_units[index].state = 'confirmed_unavailable';
+                this.successMessage = 'Item declined';
+                // Reload orders to get updated status
+                await this.loadOrders();
+            } catch (error) {
+                marketplaceLetzshopLog.error('Failed to decline item:', error);
+                this.error = error.message || 'Failed to decline item';
+            }
+        },
+
+        /**
+         * Confirm all items in an order
+         */
+        async confirmAllItems(order) {
+            if (!this.selectedVendor) return;
+
+            if (!confirm('Are you sure you want to confirm all items in this order?')) return;
+
+            try {
+                await apiClient.post(
+                    `/admin/letzshop/vendors/${this.selectedVendor.id}/orders/${order.id}/confirm`
+                );
+                this.successMessage = 'All items confirmed';
+                this.showOrderModal = false;
+                await this.loadOrders();
+            } catch (error) {
+                marketplaceLetzshopLog.error('Failed to confirm all items:', error);
+                this.error = error.message || 'Failed to confirm all items';
+            }
+        },
+
+        /**
+         * Decline all items in an order
+         */
+        async declineAllItems(order) {
+            if (!this.selectedVendor) return;
+
+            if (!confirm('Are you sure you want to decline all items in this order?')) return;
+
+            try {
+                await apiClient.post(
+                    `/admin/letzshop/vendors/${this.selectedVendor.id}/orders/${order.id}/reject`
+                );
+                this.successMessage = 'All items declined';
+                this.showOrderModal = false;
+                await this.loadOrders();
+            } catch (error) {
+                marketplaceLetzshopLog.error('Failed to decline all items:', error);
+                this.error = error.message || 'Failed to decline all items';
+            }
+        },
+
         // ═══════════════════════════════════════════════════════════════
         // SETTINGS TAB
         // ═══════════════════════════════════════════════════════════════