diff --git a/fin_defs/__init__.py b/fin_defs/__init__.py
index 1217ef1..98afaba 100644
--- a/fin_defs/__init__.py
+++ b/fin_defs/__init__.py
@@ -83,6 +83,14 @@ class StockExchange:
     eod_id: str | None = None
 
 
+NYSE = StockExchange(
+    name='New York Stock Exchange',
+    mic='XNYS',
+    bloomberg_id='UN',
+    crunchbase_id='NYSE',
+)
+
+
 @enforce_typing.enforce_types
 @dataclasses.dataclass(frozen=True)
 class Asset:
@@ -117,7 +125,7 @@ class Asset:
         raise TypeError(msg)
 
     @staticmethod
-    def from_polygon_id(polygon_id: str) -> 'Asset':
+    def from_polygon_id(polygon_id: str, exchange: StockExchange = NYSE) -> 'Asset':
         """Parses an asset from the [`polygon.io`](https://polygon.io)
         identifier format.
 
@@ -132,7 +140,7 @@ class Asset:
             )
         if polygon_id.startswith('C:'):
             return FiatCurrency(polygon_id.removeprefix('C:').removesuffix('USD'))
-        return Stock.from_polygon_id(polygon_id)
+        return Stock.from_polygon_id(polygon_id, exchange)
 
     @abc.abstractmethod
     def raw_short_name(self) -> str:
@@ -282,8 +290,8 @@ class Stock(Asset):
             raise ValueError(msg)
 
     @staticmethod
-    def from_polygon_id(polygon_id: str) -> 'Stock':
-        return Stock(polygon_id, NYSE)  # TODO: Add support for non-NYSE exchanges.
+    def from_polygon_id(polygon_id: str, exchange: StockExchange = NYSE) -> 'Stock':
+        return Stock(polygon_id, exchange)
 
     def raw_short_name(self) -> str:
         return self.ticker
@@ -404,13 +412,6 @@ CURRENCY_SYMBOLS: dict[Currency, str] = {
 
 ASSET_PREFIX: dict[Asset, str] = CURRENCY_SYMBOLS  # TODO: Remove at some point.
 
-NYSE = StockExchange(
-    name='New York Stock Exchange',
-    mic='XNYS',
-    bloomberg_id='UN',
-    crunchbase_id='NYSE',
-)
-
 EXCHANGES = [
     NYSE,
     StockExchange(name='Nasdaq', mic='XNAS', bloomberg_id='US', crunchbase_id='NASDAQ'),