diff --git a/.changeset/jolly-states-train.md b/.changeset/jolly-states-train.md
new file mode 100644
index 000000000..69be79b61
--- /dev/null
+++ b/.changeset/jolly-states-train.md
@@ -0,0 +1,5 @@
+---
+"@solid-primitives/storage": patch
+---
+
+sync API: allow for url specification
diff --git a/packages/storage/src/persisted.ts b/packages/storage/src/persisted.ts
index 287710064..860fd9802 100644
--- a/packages/storage/src/persisted.ts
+++ b/packages/storage/src/persisted.ts
@@ -229,14 +229,14 @@ export const storageSync: PersistenceSyncAPI = [
 /**
  * messageSync - synchronize over post message or broadcast channel API
  */
-export const messageSync = (channel: Window | BroadcastChannel = window): PersistenceSyncAPI => [
+export const messageSync = (channel: Window | BroadcastChannel = window, url = globalThis.location?.href): PersistenceSyncAPI => [
   (subscriber: PersistenceSyncCallback) =>
     channel.addEventListener("message", ev => {
       subscriber((ev as MessageEvent).data);
     }),
   (key, newValue) =>
     channel.postMessage(
-      { key, newValue, timeStamp: Date.now(), url: location.href },
+      { key, newValue, timeStamp: Date.now(), url },
       location.origin,
     ),
 ];
@@ -244,7 +244,7 @@ export const messageSync = (channel: Window | BroadcastChannel = window): Persis
 /**
  * wsSync - syncronize persisted storage via web socket
  */
-export const wsSync = (ws: WebSocket, warnOnError: boolean = !!DEV): PersistenceSyncAPI => [
+export const wsSync = (ws: WebSocket, warnOnError: boolean = !!DEV, url = globalThis.location?.href): PersistenceSyncAPI => [
   (subscriber: PersistenceSyncCallback) =>
     ws.addEventListener("message", (ev: MessageEvent) => {
       try {
@@ -263,7 +263,7 @@ export const wsSync = (ws: WebSocket, warnOnError: boolean = !!DEV): Persistence
         key,
         newValue,
         timeStamp: +new Date(),
-        ...(globalThis.window ? { url: location.href } : {}),
+        ...(url ? { url } : {}),
       }),
     ),
 ];
diff --git a/packages/storage/test/persisted.test.ts b/packages/storage/test/persisted.test.ts
index bccc4ac43..174a7f103 100644
--- a/packages/storage/test/persisted.test.ts
+++ b/packages/storage/test/persisted.test.ts
@@ -9,7 +9,7 @@ import {
   latest,
   refresh,
 } from "solid-js";
-import { makePersisted } from "../src/persisted.js";
+import { makePersisted, messageSync, storageSync, wsSync, type PersistenceSyncData } from "../src/persisted.js";
 import { type AsyncStorage } from "../src/index.js";
 
 describe("makePersisted", () => {
@@ -209,3 +209,57 @@ describe("makePersisted", () => {
     expect(signal()).toBe("init"); 
   });
 });
+
+describe("storageSync", () => {
+  it("receives messages", () => {
+    const [message, subscriber] = createSignal<PersistenceSyncData>();
+    storageSync[0](subscriber);
+    const event = new StorageEvent(
+      "storage",
+      { key: "test9", newValue: "received", timeStamp: Date.now(), url: "https://storage.solid-primitives.org" }
+    );
+    window.dispatchEvent(event);
+    flush();
+    expect(message()).toEqual(event);
+  });
+});
+
+describe("messageSync", () => {
+  it("sends and receives messages", async () => {
+    const [message, subscriber] = createSignal<PersistenceSyncData>();
+    const sync = messageSync(window, "https://storage.solid-primitives.org");
+    sync[0](subscriber);
+    sync[1]("test10", "sent and received");
+    await new Promise(r => setTimeout(r, 100));
+    flush();
+    expect(message()).toEqual({
+      key: "test10",
+      newValue: "sent and received",
+      timeStamp: expect.any(Number),
+      url: "https://storage.solid-primitives.org",
+    });
+  });
+});
+
+describe("wsSync", () => {
+  it("sends and receives messages", async () => {
+    const mockWs = {
+      addEventListener: (name: string, handler: (ev: unknown) => void) => { 
+        expect(name).toBe("message");
+        mockWs.send = (data) => handler(new MessageEvent("message", { data }));
+      },
+    };
+    const [message, subscriber] = createSignal<PersistenceSyncData>();
+    const sync = wsSync(mockWs, true, "https://storage.solid-primitives.org");
+    sync[0](subscriber);
+    sync[1]("test11", "sent and received");
+    await new Promise(r => setTimeout(r, 100));
+    flush();
+    expect(message()).toEqual({
+      key: "test11",
+      newValue: "sent and received",
+      timeStamp: expect.any(Number),
+      url: "https://storage.solid-primitives.org",
+    });
+  });
+});