diff --git a/.changeset/fix-basepath-reconnect.md b/.changeset/fix-basepath-reconnect.md
new file mode 100644
index 0000000..d66cf00
--- /dev/null
+++ b/.changeset/fix-basepath-reconnect.md
@@ -0,0 +1,5 @@
+---
+"partysocket": patch
+---
+
+Fix `PartySocket.reconnect()` crashing when using `basePath` without `room`. The reconnect guard now accepts either `room` or `basePath` as sufficient context to construct a connection URL.
diff --git a/package-lock.json b/package-lock.json
index 2683112..1a820b9 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -12235,7 +12235,7 @@
       "devDependencies": {
         "@cloudflare/workers-types": "^4.20251218.0",
         "hono": "^4.11.1",
-        "partyserver": "^0.1.1"
+        "partyserver": "^0.1.2"
       },
       "peerDependencies": {
         "@cloudflare/workers-types": "^4.20240729.0",
@@ -12327,7 +12327,7 @@
       "license": "ISC",
       "devDependencies": {
         "@cloudflare/workers-types": "^4.20251218.0",
-        "partyserver": "^0.1.1",
+        "partyserver": "^0.1.2",
         "partysocket": "^1.1.11"
       },
       "peerDependencies": {
@@ -12345,7 +12345,7 @@
       },
       "devDependencies": {
         "@cloudflare/workers-types": "^4.20251218.0",
-        "partyserver": "^0.1.1"
+        "partyserver": "^0.1.2"
       },
       "peerDependencies": {
         "@cloudflare/workers-types": "^4.20240729.0",
@@ -12367,7 +12367,7 @@
       "license": "ISC",
       "dependencies": {
         "cron-parser": "^5.4.0",
-        "partyserver": "^0.1.1"
+        "partyserver": "^0.1.2"
       }
     },
     "packages/y-partyserver": {
@@ -12382,7 +12382,7 @@
       "devDependencies": {
         "@cloudflare/workers-types": "^4.20251218.0",
         "@types/lodash.debounce": "^4.0.9",
-        "partyserver": "^0.1.1",
+        "partyserver": "^0.1.2",
         "ws": "^8.18.3",
         "yjs": "^13.6.28"
       },
diff --git a/packages/hono-party/package.json b/packages/hono-party/package.json
index 470ca5f..9364a9a 100644
--- a/packages/hono-party/package.json
+++ b/packages/hono-party/package.json
@@ -37,6 +37,6 @@
   "devDependencies": {
     "@cloudflare/workers-types": "^4.20251218.0",
     "hono": "^4.11.1",
-    "partyserver": "^0.1.1"
+    "partyserver": "^0.1.2"
   }
 }
diff --git a/packages/partysocket/src/index.ts b/packages/partysocket/src/index.ts
index db01f3e..66310e2 100644
--- a/packages/partysocket/src/index.ts
+++ b/packages/partysocket/src/index.ts
@@ -141,6 +141,7 @@ export default class PartySocket extends ReconnectingWebSocket {
   room?: string;
   host!: string;
   path!: string;
+  basePath?: string;
 
   constructor(readonly partySocketOptions: PartySocketOptions) {
     const wsOptions = getWSOptions(partySocketOptions);
@@ -169,7 +170,8 @@ export default class PartySocket extends ReconnectingWebSocket {
       ...partySocketOptions,
       host: partySocketOptions.host ?? this.host,
       room: partySocketOptions.room ?? this.room,
-      path: partySocketOptions.path ?? this.path
+      path: partySocketOptions.path ?? this.path,
+      basePath: partySocketOptions.basePath ?? this.basePath
     });
 
     this._url = wsOptions.urlProvider;
@@ -180,7 +182,7 @@ export default class PartySocket extends ReconnectingWebSocket {
   }
 
   private setWSProperties(wsOptions: ReturnType<typeof getWSOptions>) {
-    const { _pk, _pkurl, name, room, host, path } = wsOptions;
+    const { _pk, _pkurl, name, room, host, path, basePath } = wsOptions;
 
     this._pk = _pk;
     this._pkurl = _pkurl;
@@ -188,15 +190,21 @@ export default class PartySocket extends ReconnectingWebSocket {
     this.room = room;
     this.host = host;
     this.path = path;
+    this.basePath = basePath;
   }
 
   public reconnect(
     code?: number | undefined,
     reason?: string | undefined
   ): void {
-    if (!this.room || !this.host) {
+    if (!this.host) {
       throw new Error(
-        "The room and host must be set before connecting, use `updateProperties` method to set them or pass them to the constructor."
+        "The host must be set before connecting, use `updateProperties` method to set it or pass it to the constructor."
+      );
+    }
+    if (!this.room && !this.basePath) {
+      throw new Error(
+        "The room (or basePath) must be set before connecting, use `updateProperties` method to set it or pass it to the constructor."
       );
     }
     super.reconnect(code, reason);
@@ -256,6 +264,7 @@ function getWSOptions(partySocketOptions: PartySocketOptions) {
     room: party.room,
     host: party.host,
     path: party.path,
+    basePath: partySocketOptions.basePath,
     protocols: protocols,
     socketOptions: socketOptions,
     urlProvider: party.urlProvider
diff --git a/packages/partysocket/src/tests/error-handling.test.ts b/packages/partysocket/src/tests/error-handling.test.ts
index a73668c..985a185 100644
--- a/packages/partysocket/src/tests/error-handling.test.ts
+++ b/packages/partysocket/src/tests/error-handling.test.ts
@@ -126,7 +126,7 @@ describe.skip("Error Handling - PartySocket Validation", () => {
 
     expect(() => {
       ps.reconnect();
-    }).toThrow("The room and host must be set");
+    }).toThrow("The host must be set");
   });
 
   test("throws when reconnecting without room", () => {
@@ -140,7 +140,19 @@ describe.skip("Error Handling - PartySocket Validation", () => {
 
     expect(() => {
       ps.reconnect();
-    }).toThrow("The room and host must be set");
+    }).toThrow("The room (or basePath) must be set");
+  });
+
+  test("does not throw when reconnecting with basePath and no room", () => {
+    const ps = new PartySocket({
+      host: "example.com",
+      basePath: "custom/path",
+      startClosed: true
+    });
+
+    expect(() => {
+      ps.reconnect();
+    }).not.toThrow();
   });
 
   test("handles missing WebSocket constructor gracefully", async () => {
diff --git a/packages/partysocket/src/tests/partysocket-url.test.ts b/packages/partysocket/src/tests/partysocket-url.test.ts
index 3bec785..8a979d0 100644
--- a/packages/partysocket/src/tests/partysocket-url.test.ts
+++ b/packages/partysocket/src/tests/partysocket-url.test.ts
@@ -432,7 +432,7 @@ describe.skip("PartySocket.updateProperties", () => {
     ps.updateProperties({ host: "", room: "" });
     expect(() => {
       ps.reconnect();
-    }).toThrow("The room and host must be set");
+    }).toThrow("The host must be set");
   });
 });
 
diff --git a/packages/partysub/package.json b/packages/partysub/package.json
index c375d14..df17dcf 100644
--- a/packages/partysub/package.json
+++ b/packages/partysub/package.json
@@ -46,7 +46,7 @@
   },
   "devDependencies": {
     "@cloudflare/workers-types": "^4.20251218.0",
-    "partyserver": "^0.1.1",
+    "partyserver": "^0.1.2",
     "partysocket": "^1.1.11"
   }
 }
diff --git a/packages/partysync/package.json b/packages/partysync/package.json
index 7064aa2..116aa90 100644
--- a/packages/partysync/package.json
+++ b/packages/partysync/package.json
@@ -54,6 +54,6 @@
   },
   "devDependencies": {
     "@cloudflare/workers-types": "^4.20251218.0",
-    "partyserver": "^0.1.1"
+    "partyserver": "^0.1.2"
   }
 }
diff --git a/packages/partywhen/package.json b/packages/partywhen/package.json
index 9b3f297..d50c21e 100644
--- a/packages/partywhen/package.json
+++ b/packages/partywhen/package.json
@@ -29,6 +29,6 @@
   "description": "A library for scheduling and running tasks in Cloudflare Workers",
   "dependencies": {
     "cron-parser": "^5.4.0",
-    "partyserver": "^0.1.1"
+    "partyserver": "^0.1.2"
   }
 }
diff --git a/packages/y-partyserver/package.json b/packages/y-partyserver/package.json
index c331f91..2c50e6a 100644
--- a/packages/y-partyserver/package.json
+++ b/packages/y-partyserver/package.json
@@ -53,7 +53,7 @@
   "devDependencies": {
     "@cloudflare/workers-types": "^4.20251218.0",
     "@types/lodash.debounce": "^4.0.9",
-    "partyserver": "^0.1.1",
+    "partyserver": "^0.1.2",
     "ws": "^8.18.3",
     "yjs": "^13.6.28"
   }