diff --git a/app/routers/collections.py b/app/routers/collections.py
index 3d65820..666aef3 100644
--- a/app/routers/collections.py
+++ b/app/routers/collections.py
@@ -97,9 +97,13 @@ async def list_collections(
     session: AsyncSession = Depends(get_async_session),
 ):
     """List all collections for the current user."""
-    # Get collections with item counts
+    # Get collections with item counts and total value
     stmt = (
-        select(Collection, func.count(Item.id).label("item_count"))
+        select(
+            Collection,
+            func.count(Item.id).label("item_count"),
+            func.sum(Item.estimated_value).label("total_value"),
+        )
         .outerjoin(Item, Collection.id == Item.collection_id)
         .where(Collection.user_id == str(user.id))
         .group_by(Collection.id)
@@ -121,6 +125,7 @@ async def list_collections(
             created_at=row.Collection.created_at,
             updated_at=row.Collection.updated_at,
             item_count=row.item_count,
+            total_value=row.total_value or None,
             preview_images=previews.get(row.Collection.id, []),
         )
         for row in rows
@@ -135,7 +140,11 @@ async def get_collection(
 ):
     """Get a single collection by ID."""
     stmt = (
-        select(Collection, func.count(Item.id).label("item_count"))
+        select(
+            Collection,
+            func.count(Item.id).label("item_count"),
+            func.sum(Item.estimated_value).label("total_value"),
+        )
         .outerjoin(Item, Collection.id == Item.collection_id)
         .where(Collection.id == str(collection_id), Collection.user_id == str(user.id))
         .group_by(Collection.id)
@@ -160,6 +169,7 @@ async def get_collection(
         created_at=row.Collection.created_at,
         updated_at=row.Collection.updated_at,
         item_count=row.item_count,
+        total_value=row.total_value or None,
         preview_images=previews.get(row.Collection.id, []),
     )
 
diff --git a/app/schemas/collection.py b/app/schemas/collection.py
index 1e3155f..97fccb1 100644
--- a/app/schemas/collection.py
+++ b/app/schemas/collection.py
@@ -1,4 +1,5 @@
 from datetime import datetime
+from decimal import Decimal
 from uuid import UUID
 
 from pydantic import BaseModel, ConfigDict, Field, field_validator
@@ -64,4 +65,5 @@ class CollectionReadWithCount(CollectionRead):
     """Schema for reading a Collection with item count."""
 
     item_count: int = 0
+    total_value: Decimal | None = None
     preview_images: list[ImagePreview] = []
diff --git a/tests/test_collections.py b/tests/test_collections.py
index ee539ab..6a5f55a 100644
--- a/tests/test_collections.py
+++ b/tests/test_collections.py
@@ -427,3 +427,105 @@ async def test_collection_no_images_empty_preview(
     assert response.status_code == 200
     data = response.json()
     assert data["preview_images"] == []
+
+
+@pytest.mark.asyncio
+async def test_list_collections_total_value(
+    client: AsyncClient, session: AsyncSession, test_user: User, auth_client
+):
+    """Test that listing collections includes total_value summing estimated_value."""
+    collection = Collection(user_id=str(test_user.id), name="Valued Collection")
+    session.add(collection)
+    await session.commit()
+    await session.refresh(collection)
+
+    item1 = Item(
+        user_id=str(test_user.id),
+        collection_id=collection.id,
+        name="Item 1",
+        estimated_value=100.50,
+    )
+    item2 = Item(
+        user_id=str(test_user.id),
+        collection_id=collection.id,
+        name="Item 2",
+        estimated_value=250.00,
+    )
+    item3 = Item(
+        user_id=str(test_user.id),
+        collection_id=collection.id,
+        name="Item 3 (no value)",
+    )
+    session.add_all([item1, item2, item3])
+    await session.commit()
+
+    response = await client.get("/collections")
+    assert response.status_code == 200
+    data = response.json()
+    assert len(data) == 1
+    assert data[0]["total_value"] == "350.50"
+
+
+@pytest.mark.asyncio
+async def test_get_collection_total_value(
+    client: AsyncClient, session: AsyncSession, test_user: User, auth_client
+):
+    """Test that getting a single collection includes total_value."""
+    collection = Collection(user_id=str(test_user.id), name="My Collection")
+    session.add(collection)
+    await session.commit()
+    await session.refresh(collection)
+
+    item = Item(
+        user_id=str(test_user.id),
+        collection_id=collection.id,
+        name="Valuable Item",
+        estimated_value=999.99,
+    )
+    session.add(item)
+    await session.commit()
+
+    response = await client.get(f"/collections/{collection.id}")
+    assert response.status_code == 200
+    data = response.json()
+    assert data["total_value"] == "999.99"
+
+
+@pytest.mark.asyncio
+async def test_collection_total_value_null_when_no_values(
+    client: AsyncClient, session: AsyncSession, test_user: User, auth_client
+):
+    """Test that total_value is null when no items have estimated_value."""
+    collection = Collection(user_id=str(test_user.id), name="No Values")
+    session.add(collection)
+    await session.commit()
+    await session.refresh(collection)
+
+    item = Item(
+        user_id=str(test_user.id),
+        collection_id=collection.id,
+        name="Item without value",
+    )
+    session.add(item)
+    await session.commit()
+
+    response = await client.get(f"/collections/{collection.id}")
+    assert response.status_code == 200
+    data = response.json()
+    assert data["total_value"] is None
+
+
+@pytest.mark.asyncio
+async def test_empty_collection_total_value_null(
+    client: AsyncClient, session: AsyncSession, test_user: User, auth_client
+):
+    """Test that total_value is null for empty collections."""
+    collection = Collection(user_id=str(test_user.id), name="Empty")
+    session.add(collection)
+    await session.commit()
+    await session.refresh(collection)
+
+    response = await client.get(f"/collections/{collection.id}")
+    assert response.status_code == 200
+    data = response.json()
+    assert data["total_value"] is None