diff --git a/.changeset/bright-cooks-change.md b/.changeset/bright-cooks-change.md
new file mode 100644
index 000000000..4b0a9f56d
--- /dev/null
+++ b/.changeset/bright-cooks-change.md
@@ -0,0 +1,6 @@
+---
+'@powersync/common': minor
+'@powersync/web': minor
+---
+
+Added support for user parameters. These parameters can be specified as part of the `connect` method's options object.
diff --git a/packages/common/src/client/sync/stream/AbstractStreamingSyncImplementation.ts b/packages/common/src/client/sync/stream/AbstractStreamingSyncImplementation.ts
index 2adfc6b54..f44c8ba7b 100644
--- a/packages/common/src/client/sync/stream/AbstractStreamingSyncImplementation.ts
+++ b/packages/common/src/client/sync/stream/AbstractStreamingSyncImplementation.ts
@@ -4,6 +4,7 @@ import Logger, { ILogger } from 'js-logger';
 
 import {
   BucketRequest,
+  StreamingSyncRequestParameterType,
   isStreamingKeepalive,
   isStreamingSyncCheckpoint,
   isStreamingSyncCheckpointComplete,
@@ -73,6 +74,11 @@ export interface PowerSyncConnectionOptions {
    * Defaults to a HTTP streaming connection.
    */
   connectionMethod?: SyncStreamConnectionMethod;
+
+  /**
+   * These parameters are passed to the sync rules, and will be available under the`user_parameters` object.
+   */
+  params?: Record<string, StreamingSyncRequestParameterType>;
 }
 
 export interface StreamingSyncImplementation extends BaseObserver<StreamingSyncImplementationListener>, Disposable {
@@ -104,7 +110,8 @@ export const DEFAULT_STREAMING_SYNC_OPTIONS = {
 };
 
 export const DEFAULT_STREAM_CONNECTION_OPTIONS: Required<PowerSyncConnectionOptions> = {
-  connectionMethod: SyncStreamConnectionMethod.HTTP
+  connectionMethod: SyncStreamConnectionMethod.HTTP,
+  params: {}
 };
 
 export abstract class AbstractStreamingSyncImplementation
@@ -445,7 +452,8 @@ export abstract class AbstractStreamingSyncImplementation
           data: {
             buckets: req,
             include_checksum: true,
-            raw_data: true
+            raw_data: true,
+            parameters: resolvedOptions.params
           }
         };
 
diff --git a/packages/common/src/client/sync/stream/streaming-sync-types.ts b/packages/common/src/client/sync/stream/streaming-sync-types.ts
index 747d5bd0d..fab672016 100644
--- a/packages/common/src/client/sync/stream/streaming-sync-types.ts
+++ b/packages/common/src/client/sync/stream/streaming-sync-types.ts
@@ -55,6 +55,15 @@ export interface SyncResponse {
   checkpoint?: Checkpoint;
 }
 
+type JSONValue = string | number | boolean | null | undefined | JSONObject | JSONArray;
+
+interface JSONObject {
+  [key: string]: JSONValue;
+}
+type JSONArray = JSONValue[];
+
+export type StreamingSyncRequestParameterType = JSONValue;
+
 export interface StreamingSyncRequest {
   /**
    * Existing bucket states.
@@ -75,6 +84,11 @@ export interface StreamingSyncRequest {
    * Changes the response to stringified data in each OplogEntry
    */
   raw_data: boolean;
+
+  /**
+   * Client parameters to be passed to the sync rules.
+   */
+  parameters?: Record<string, StreamingSyncRequestParameterType>;
 }
 
 export interface StreamingSyncCheckpoint {