diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index fe50513..3b59af2 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -49,7 +49,7 @@ jobs:
         run: uv sync --all-extras
 
       - name: Run mypy
-        run: uv run mypy polymarket_us tests/types/order_snapshot.py
+        run: uv run mypy polymarket_us tests/types
 
   test:
     runs-on: ubuntu-latest
diff --git a/README.md b/README.md
index b055cbe..d341f6c 100644
--- a/README.md
+++ b/README.md
@@ -267,6 +267,25 @@ asyncio.run(main())
 | `markets.bbo(slug)` | Get best bid/offer |
 | `markets.settlement(slug)` | Get settlement price |
 
+#### Market response type migration
+
+The response types now match the existing JSON returned by both sync and async
+clients; runtime responses are unchanged. Typed callers should read book and BBO
+data through `marketData`. Settlement uses `slug` and a numeric `settlement`,
+replacing the previous `marketSlug`, `settlementPrice`, and `settledAt` declarations.
+
+```python
+book = client.markets.book("btc-100k")["marketData"]
+bbo = client.markets.bbo("btc-100k")["marketData"]
+settlement = client.markets.settlement("btc-100k")
+slug = settlement["slug"]
+settlement_price = settlement["settlement"]
+```
+
+With `AsyncPolymarketUS`, await each method call before reading these keys.
+Handle `None` for book `stats` and `transactTime`, and BBO `bestBid`, `bestAsk`, and
+`lastTradePx`. Books also support `MARKET_STATE_CLOSED`.
+
 ### Orders (Authenticated)
 
 | Method | Description |
diff --git a/polymarket_us/resources/markets.py b/polymarket_us/resources/markets.py
index 208f2c0..f858405 100644
--- a/polymarket_us/resources/markets.py
+++ b/polymarket_us/resources/markets.py
@@ -2,10 +2,10 @@
 
 from polymarket_us.resource import APIResource, AsyncAPIResource
 from polymarket_us.types import (
+    GetMarketBBOResponse,
+    GetMarketBookResponse,
     GetMarketResponse,
     GetMarketsResponse,
-    MarketBBO,
-    MarketBook,
     MarketSettlement,
     MarketsListParams,
 )
@@ -26,11 +26,11 @@ def retrieve_by_slug(self, slug: str) -> GetMarketResponse:
         """Get a market by slug."""
         return self._client.get(f"/v1/market/slug/{slug}")
 
-    def book(self, slug: str) -> MarketBook:
+    def book(self, slug: str) -> GetMarketBookResponse:
         """Get order book for a market."""
         return self._client.get(f"/v1/markets/{slug}/book")
 
-    def bbo(self, slug: str) -> MarketBBO:
+    def bbo(self, slug: str) -> GetMarketBBOResponse:
         """Get best bid/offer for a market."""
         return self._client.get(f"/v1/markets/{slug}/bbo")
 
@@ -54,11 +54,11 @@ async def retrieve_by_slug(self, slug: str) -> GetMarketResponse:
         """Get a market by slug."""
         return await self._client.get(f"/v1/market/slug/{slug}")
 
-    async def book(self, slug: str) -> MarketBook:
+    async def book(self, slug: str) -> GetMarketBookResponse:
         """Get order book for a market."""
         return await self._client.get(f"/v1/markets/{slug}/book")
 
-    async def bbo(self, slug: str) -> MarketBBO:
+    async def bbo(self, slug: str) -> GetMarketBBOResponse:
         """Get best bid/offer for a market."""
         return await self._client.get(f"/v1/markets/{slug}/bbo")
 
diff --git a/polymarket_us/types/__init__.py b/polymarket_us/types/__init__.py
index 5a6d56f..75f623d 100644
--- a/polymarket_us/types/__init__.py
+++ b/polymarket_us/types/__init__.py
@@ -16,6 +16,8 @@
     Tag,
 )
 from polymarket_us.types.markets import (
+    GetMarketBBOResponse,
+    GetMarketBookResponse,
     GetMarketResponse,
     GetMarketsResponse,
     MarketBBO,
@@ -113,6 +115,8 @@
     "MarketsListParams",
     "GetMarketsResponse",
     "GetMarketResponse",
+    "GetMarketBookResponse",
+    "GetMarketBBOResponse",
     # Orders
     "OrderType",
     "OrderSide",
diff --git a/polymarket_us/types/markets.py b/polymarket_us/types/markets.py
index 180893d..f76599b 100644
--- a/polymarket_us/types/markets.py
+++ b/polymarket_us/types/markets.py
@@ -55,6 +55,7 @@ class MarketStats(TypedDict, total=False):
 
 
 MarketState = Literal[
+    "MARKET_STATE_CLOSED",
     "MARKET_STATE_OPEN",
     "MARKET_STATE_PREOPEN",
     "MARKET_STATE_SUSPENDED",
@@ -72,19 +73,19 @@ class MarketBook(TypedDict, total=False):
     bids: list[OrderBookLevel]
     offers: list[OrderBookLevel]
     state: MarketState
-    stats: MarketStats
-    transactTime: str
+    stats: MarketStats | None
+    transactTime: str | None
 
 
 class MarketBBO(TypedDict, total=False):
     """Best bid/offer for a market."""
 
     marketSlug: str
-    bestBid: Amount
-    bestAsk: Amount
+    bestBid: Amount | None
+    bestAsk: Amount | None
     bidDepth: int
     askDepth: int
-    lastTradePx: Amount
+    lastTradePx: Amount | None
     sharesTraded: str
     openInterest: str
 
@@ -92,9 +93,8 @@ class MarketBBO(TypedDict, total=False):
 class MarketSettlement(TypedDict):
     """Market settlement information."""
 
-    marketSlug: str
-    settlementPrice: Amount
-    settledAt: str
+    slug: str
+    settlement: float
 
 
 class MarketsListParams(PaginationParams, total=False):
@@ -126,3 +126,15 @@ class GetMarketResponse(TypedDict):
     """Response for getting a single market."""
 
     market: MarketDetail
+
+
+class GetMarketBookResponse(TypedDict):
+    """Response for getting a market's order book."""
+
+    marketData: MarketBook
+
+
+class GetMarketBBOResponse(TypedDict):
+    """Response for getting a market's best bid/offer."""
+
+    marketData: MarketBBO
diff --git a/tests/test_markets.py b/tests/test_markets.py
index 04dba4d..7c07af0 100644
--- a/tests/test_markets.py
+++ b/tests/test_markets.py
@@ -4,8 +4,10 @@
 
 import httpx
 import pytest
+from pytest_httpx import HTTPXMock
 
-from polymarket_us import PolymarketUS
+from polymarket_us import AsyncPolymarketUS, PolymarketUS
+from polymarket_us.types import GetMarketBBOResponse, GetMarketBookResponse, MarketSettlement
 
 
 class TestMarketsList:
@@ -93,108 +95,125 @@ def test_uses_correct_path_with_slug(
         assert "/v1/market/slug/btc-100k" in url
 
 
-class TestMarketsBook:
-    """Tests for markets.book()."""
-
-    @pytest.fixture
-    def client(self) -> PolymarketUS:
-        return PolymarketUS()
-
-    @patch.object(httpx.Client, "request")
-    def test_get_order_book(self, mock_request: MagicMock, client: PolymarketUS) -> None:
-        """Should get order book."""
-        mock_response = MagicMock()
-        mock_response.is_success = True
-        mock_response.text = '{"marketSlug": "btc-100k", "bids": [], "offers": []}'
-        mock_response.json.return_value = {
+@pytest.fixture(params=[False, True], ids=["populated", "empty"])
+def book_response(request: pytest.FixtureRequest) -> GetMarketBookResponse:
+    if request.param:
+        return {
+            "marketData": {
+                "marketSlug": "btc-100k",
+                "bids": [],
+                "offers": [],
+                "state": "MARKET_STATE_CLOSED",
+                "stats": None,
+                "transactTime": None,
+            }
+        }
+    return {
+        "marketData": {
             "marketSlug": "btc-100k",
             "bids": [{"px": {"value": "0.55", "currency": "USD"}, "qty": "100"}],
             "offers": [{"px": {"value": "0.56", "currency": "USD"}, "qty": "80"}],
             "state": "MARKET_STATE_OPEN",
+            "stats": {"lastTradePx": {"value": "0.55", "currency": "USD"}},
+            "transactTime": "2026-09-21T12:00:00Z",
         }
-        mock_request.return_value = mock_response
-
-        book = client.markets.book("btc-100k")
-
-        assert book["marketSlug"] == "btc-100k"
-        assert "bids" in book
-        assert "offers" in book
-
-    @patch.object(httpx.Client, "request")
-    def test_uses_correct_path(self, mock_request: MagicMock, client: PolymarketUS) -> None:
-        """Should use correct path."""
-        mock_response = MagicMock()
-        mock_response.is_success = True
-        mock_response.text = '{"bids": [], "offers": []}'
-        mock_response.json.return_value = {"bids": [], "offers": []}
-        mock_request.return_value = mock_response
-
-        client.markets.book("test-market")
-
-        call_args = mock_request.call_args
-        url = call_args.args[1] if len(call_args.args) > 1 else call_args.kwargs.get("url")
-        assert "/v1/markets/test-market/book" in url
-
-
-class TestMarketsBBO:
-    """Tests for markets.bbo()."""
-
-    @pytest.fixture
-    def client(self) -> PolymarketUS:
-        return PolymarketUS()
-
-    @patch.object(httpx.Client, "request")
-    def test_get_best_bid_offer(self, mock_request: MagicMock, client: PolymarketUS) -> None:
-        """Should get best bid/offer."""
-        mock_response = MagicMock()
-        mock_response.is_success = True
-        mock_response.text = '{"marketSlug": "btc-100k"}'
-        mock_response.json.return_value = {
+    }
+
+
+@pytest.fixture(params=[False, True], ids=["populated", "empty"])
+def bbo_response(request: pytest.FixtureRequest) -> GetMarketBBOResponse:
+    if request.param:
+        return {
+            "marketData": {
+                "marketSlug": "btc-100k",
+                "bestBid": None,
+                "bestAsk": None,
+                "lastTradePx": None,
+                "bidDepth": 0,
+                "askDepth": 0,
+                "sharesTraded": "",
+                "openInterest": "",
+            }
+        }
+    return {
+        "marketData": {
             "marketSlug": "btc-100k",
             "bestBid": {"value": "0.55", "currency": "USD"},
             "bestAsk": {"value": "0.56", "currency": "USD"},
+            "lastTradePx": {"value": "0.55", "currency": "USD"},
+            "bidDepth": 1,
+            "askDepth": 1,
+            "sharesTraded": "100",
+            "openInterest": "80",
         }
-        mock_request.return_value = mock_response
-
-        bbo = client.markets.bbo("btc-100k")
-
-        assert "bestBid" in bbo
-        assert "bestAsk" in bbo
-
-    @patch.object(httpx.Client, "request")
-    def test_uses_correct_path(self, mock_request: MagicMock, client: PolymarketUS) -> None:
-        """Should use correct path."""
-        mock_response = MagicMock()
-        mock_response.is_success = True
-        mock_response.text = "{}"
-        mock_response.json.return_value = {}
-        mock_request.return_value = mock_response
-
-        client.markets.bbo("test-market")
-
-        call_args = mock_request.call_args
-        url = call_args.args[1] if len(call_args.args) > 1 else call_args.kwargs.get("url")
-        assert "/v1/markets/test-market/bbo" in url
-
-
-class TestMarketsSettlement:
-    """Tests for markets.settlement()."""
-
-    @pytest.fixture
-    def client(self) -> PolymarketUS:
-        return PolymarketUS()
-
-    @patch.object(httpx.Client, "request")
-    def test_uses_correct_path(self, mock_request: MagicMock, client: PolymarketUS) -> None:
-        """Should use correct path."""
-        mock_response = MagicMock()
-        mock_response.is_success = True
-        mock_response.text = "{}"
-        mock_response.json.return_value = {}
-        mock_request.return_value = mock_response
-
-        client.markets.settlement("settled-market")
-
-        call_args = mock_request.call_args
-        url = call_args.args[1] if len(call_args.args) > 1 else call_args.kwargs.get("url")
-        assert "/v1/markets/settled-market/settlement" in url
+    }
+
+
+def test_book_returns_wire_response(
+    httpx_mock: HTTPXMock, book_response: GetMarketBookResponse
+) -> None:
+    httpx_mock.add_response(
+        method="GET",
+        url="https://gateway.polymarket.us/v1/markets/btc-100k/book",
+        json=book_response,
+    )
+    with PolymarketUS() as client:
+        assert client.markets.book("btc-100k") == book_response
+
+
+async def test_async_book_returns_wire_response(
+    httpx_mock: HTTPXMock, book_response: GetMarketBookResponse
+) -> None:
+    httpx_mock.add_response(
+        method="GET",
+        url="https://gateway.polymarket.us/v1/markets/btc-100k/book",
+        json=book_response,
+    )
+    async with AsyncPolymarketUS() as client:
+        assert await client.markets.book("btc-100k") == book_response
+
+
+def test_bbo_returns_wire_response(
+    httpx_mock: HTTPXMock, bbo_response: GetMarketBBOResponse
+) -> None:
+    httpx_mock.add_response(
+        method="GET", url="https://gateway.polymarket.us/v1/markets/btc-100k/bbo", json=bbo_response
+    )
+    with PolymarketUS() as client:
+        assert client.markets.bbo("btc-100k") == bbo_response
+
+
+async def test_async_bbo_returns_wire_response(
+    httpx_mock: HTTPXMock, bbo_response: GetMarketBBOResponse
+) -> None:
+    httpx_mock.add_response(
+        method="GET", url="https://gateway.polymarket.us/v1/markets/btc-100k/bbo", json=bbo_response
+    )
+    async with AsyncPolymarketUS() as client:
+        assert await client.markets.bbo("btc-100k") == bbo_response
+
+
+@pytest.mark.parametrize("settlement", [0, 0.5, 1])
+def test_settlement_returns_numeric_price(httpx_mock: HTTPXMock, settlement: float) -> None:
+    response: MarketSettlement = {"slug": "btc-100k", "settlement": settlement}
+    httpx_mock.add_response(
+        method="GET",
+        url="https://gateway.polymarket.us/v1/markets/btc-100k/settlement",
+        json=response,
+    )
+    with PolymarketUS() as client:
+        assert client.markets.settlement("btc-100k") == response
+
+
+@pytest.mark.parametrize("settlement", [0, 0.5, 1])
+async def test_async_settlement_returns_numeric_price(
+    httpx_mock: HTTPXMock, settlement: float
+) -> None:
+    response: MarketSettlement = {"slug": "btc-100k", "settlement": settlement}
+    httpx_mock.add_response(
+        method="GET",
+        url="https://gateway.polymarket.us/v1/markets/btc-100k/settlement",
+        json=response,
+    )
+    async with AsyncPolymarketUS() as client:
+        assert await client.markets.settlement("btc-100k") == response
diff --git a/tests/types/market_responses.py b/tests/types/market_responses.py
new file mode 100644
index 0000000..a6a061d
--- /dev/null
+++ b/tests/types/market_responses.py
@@ -0,0 +1,50 @@
+"""Consumer typing checks included in the existing mypy CI job."""
+
+from polymarket_us import AsyncPolymarketUS, PolymarketUS
+from polymarket_us.types import (
+    GetMarketBBOResponse,
+    GetMarketBookResponse,
+    MarketBBO,
+    MarketBook,
+)
+
+
+def read_market_data(client: PolymarketUS) -> tuple[MarketBook, MarketBBO, str, float]:
+    book = client.markets.book("market")
+    bbo = client.markets.bbo("market")
+    settlement = client.markets.settlement("market")
+    return book["marketData"], bbo["marketData"], settlement["slug"], settlement["settlement"]
+
+
+async def read_market_data_async(
+    client: AsyncPolymarketUS,
+) -> tuple[MarketBook, MarketBBO, str, float]:
+    book = await client.markets.book("market")
+    bbo = await client.markets.bbo("market")
+    settlement = await client.markets.settlement("market")
+    return book["marketData"], bbo["marketData"], settlement["slug"], settlement["settlement"]
+
+
+empty_book: GetMarketBookResponse = {
+    "marketData": {
+        "marketSlug": "market",
+        "bids": [],
+        "offers": [],
+        "state": "MARKET_STATE_CLOSED",
+        "stats": None,
+        "transactTime": None,
+    }
+}
+
+empty_bbo: GetMarketBBOResponse = {
+    "marketData": {
+        "marketSlug": "market",
+        "bestBid": None,
+        "bestAsk": None,
+        "lastTradePx": None,
+        "bidDepth": 0,
+        "askDepth": 0,
+        "sharesTraded": "",
+        "openInterest": "",
+    }
+}