diff --git a/app/Http/Controllers/BucketController.php b/app/Http/Controllers/BucketController.php
index cab6a3c..e52b7b1 100644
--- a/app/Http/Controllers/BucketController.php
+++ b/app/Http/Controllers/BucketController.php
@@ -72,45 +72,50 @@ public function store(Request $request, Scenario $scenario): JsonResponse
     public function update(Request $request, Bucket $bucket): JsonResponse
     {
         $validated = $request->validate([
-            'name' => 'required|string|max:255',
-            'type' => 'required|in:'.implode(',', BucketTypeEnum::values()),
-            'allocation_type' => 'required|in:'.implode(',', BucketAllocationTypeEnum::values()),
+            'name' => 'sometimes|required|string|max:255',
+            'type' => 'sometimes|required|in:'.implode(',', BucketTypeEnum::values()),
+            'allocation_type' => 'sometimes|required|in:'.implode(',', BucketAllocationTypeEnum::values()),
             'allocation_value' => 'nullable|numeric',
             'buffer_multiplier' => 'sometimes|numeric|min:0',
+            'starting_amount' => 'sometimes|integer|min:0',
             'priority' => 'nullable|integer|min:1',
         ]);
 
-        $type = BucketTypeEnum::from($validated['type']);
-        $allocationType = BucketAllocationTypeEnum::from($validated['allocation_type']);
+        $type = isset($validated['type']) ? BucketTypeEnum::from($validated['type']) : $bucket->type;
+        $allocationType = isset($validated['allocation_type']) ? BucketAllocationTypeEnum::from($validated['allocation_type']) : $bucket->allocation_type;
 
         // Prevent changing overflow bucket's type away from overflow
-        // (changing TO overflow is handled by validateBucketTypeConstraints below)
-        if ($bucket->type === BucketTypeEnum::OVERFLOW && $type !== BucketTypeEnum::OVERFLOW) {
+        if (isset($validated['type']) && $bucket->type === BucketTypeEnum::OVERFLOW && $type !== BucketTypeEnum::OVERFLOW) {
             return response()->json([
                 'message' => 'Validation failed.',
                 'errors' => ['type' => ['The overflow bucket\'s type cannot be changed.']],
             ], 422);
         }
 
-        $constraintError = $this->validateBucketTypeConstraints($type, $allocationType, $bucket->scenario, $bucket);
-        if ($constraintError) {
-            return $constraintError;
+        // Run type/allocation constraint validation when relevant fields change
+        if (isset($validated['type']) || isset($validated['allocation_type'])) {
+            $constraintError = $this->validateBucketTypeConstraints($type, $allocationType, $bucket->scenario, $bucket);
+            if ($constraintError) {
+                return $constraintError;
+            }
+
+            // Set allocation_value to null for unlimited buckets
+            if ($allocationType === BucketAllocationTypeEnum::UNLIMITED) {
+                $validated['allocation_value'] = null;
+            }
+
+            // Buffer only applies to fixed_limit buckets — always reset on type change
+            if ($allocationType !== BucketAllocationTypeEnum::FIXED_LIMIT) {
+                $validated['buffer_multiplier'] = 0.0;
+            }
         }
 
-        // Validate allocation_value based on allocation_type
-        $allocationValueRules = Bucket::allocationValueRules($allocationType);
-        $request->validate([
-            'allocation_value' => $allocationValueRules,
-        ]);
-
-        // Set allocation_value to null for unlimited buckets
-        if ($allocationType === BucketAllocationTypeEnum::UNLIMITED) {
-            $validated['allocation_value'] = null;
-        }
-
-        // Buffer only applies to fixed_limit buckets — always reset on type change
-        if ($allocationType !== BucketAllocationTypeEnum::FIXED_LIMIT) {
-            $validated['buffer_multiplier'] = 0.0;
+        // Validate allocation_value when it or allocation_type changes
+        if (array_key_exists('allocation_value', $validated) || isset($validated['allocation_type'])) {
+            $allocationValueRules = Bucket::allocationValueRules($allocationType);
+            $request->validate([
+                'allocation_value' => $allocationValueRules,
+            ]);
         }
 
         // Handle priority change if needed
@@ -231,6 +236,7 @@ private function formatBucketResponse(Bucket $bucket): array
             'allocation_type_label' => $bucket->getAllocationTypeLabel(),
             'buffer_multiplier' => (float) $bucket->buffer_multiplier,
             'effective_capacity' => $bucket->getEffectiveCapacity(),
+            'starting_amount' => $bucket->starting_amount,
             'current_balance' => $bucket->getCurrentBalance(),
             'has_available_space' => $bucket->hasAvailableSpace(),
             'available_space' => $bucket->getAvailableSpace(),
diff --git a/app/Http/Resources/BucketResource.php b/app/Http/Resources/BucketResource.php
index ed08d94..8eec11e 100644
--- a/app/Http/Resources/BucketResource.php
+++ b/app/Http/Resources/BucketResource.php
@@ -21,6 +21,7 @@ public function toArray(Request $request): array
             'allocation_type_label' => $this->getAllocationTypeLabel(),
             'buffer_multiplier' => (float) $this->buffer_multiplier,
             'effective_capacity' => $this->getEffectiveCapacity(),
+            'starting_amount' => $this->starting_amount,
             'current_balance' => $this->getCurrentBalance(),
             'has_available_space' => $this->hasAvailableSpace(),
             'available_space' => $this->getAvailableSpace(),
diff --git a/phpstan-baseline.neon b/phpstan-baseline.neon
index 02f0b34..b93cf01 100644
--- a/phpstan-baseline.neon
+++ b/phpstan-baseline.neon
@@ -180,6 +180,12 @@ parameters:
 			count: 1
 			path: app/Http/Resources/BucketResource.php
 
+		-
+			message: '#^Access to an undefined property App\\Http\\Resources\\BucketResource\:\:\$starting_amount\.$#'
+			identifier: property.notFound
+			count: 1
+			path: app/Http/Resources/BucketResource.php
+
 		-
 			message: '#^Call to an undefined method App\\Http\\Resources\\BucketResource\:\:getEffectiveCapacity\(\)\.$#'
 			identifier: method.notFound