diff --git a/CHANGELOG.md b/CHANGELOG.md
index 37c2c096..e002446e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,7 @@
 ## 1.0.0-BETA32
 
 * Added `onChange` method to the PowerSync client. This allows for observing table changes.
+* Removed unnecessary `User-Id` header from internal PowerSync service requests.
 
 ## 1.0.0-BETA31
 
diff --git a/README.md b/README.md
index d10e1d23..10f95790 100644
--- a/README.md
+++ b/README.md
@@ -47,9 +47,6 @@ Current limitations:
 
 - Integration with SQLDelight schema and API generation (ORM) is not yet supported.
 
-Future work/ideas:
-- Attachments helper package.
-
 ## Installation
 
 Add the PowerSync Kotlin Multiplatform SDK to your project by adding the following to your `build.gradle.kts` file:
diff --git a/connectors/supabase/src/commonMain/kotlin/com/powersync/connector/supabase/SupabaseConnector.kt b/connectors/supabase/src/commonMain/kotlin/com/powersync/connector/supabase/SupabaseConnector.kt
index 388b70e6..022df0c2 100644
--- a/connectors/supabase/src/commonMain/kotlin/com/powersync/connector/supabase/SupabaseConnector.kt
+++ b/connectors/supabase/src/commonMain/kotlin/com/powersync/connector/supabase/SupabaseConnector.kt
@@ -164,11 +164,9 @@ public class SupabaseConnector(
 
             check(session.user != null) { "No user data" }
 
-            // userId is for debugging purposes only
             PowerSyncCredentials(
                 endpoint = powerSyncEndpoint,
                 token = session.accessToken, // Use the access token to authenticate against PowerSync
-                userId = session.user!!.id,
             )
         }
 
diff --git a/core/src/commonIntegrationTest/kotlin/com/powersync/testutils/TestUtils.kt b/core/src/commonIntegrationTest/kotlin/com/powersync/testutils/TestUtils.kt
index 9dc16317..7560d8cb 100644
--- a/core/src/commonIntegrationTest/kotlin/com/powersync/testutils/TestUtils.kt
+++ b/core/src/commonIntegrationTest/kotlin/com/powersync/testutils/TestUtils.kt
@@ -100,7 +100,6 @@ internal class ActiveDatabaseTest(
             everySuspend { getCredentialsCached() } returns
                 PowerSyncCredentials(
                     token = "test-token",
-                    userId = "test-user",
                     endpoint = "https://test.com",
                 )
 
diff --git a/core/src/commonMain/kotlin/com/powersync/connectors/PowerSyncCredentials.kt b/core/src/commonMain/kotlin/com/powersync/connectors/PowerSyncCredentials.kt
index e3c99d75..7ba63410 100644
--- a/core/src/commonMain/kotlin/com/powersync/connectors/PowerSyncCredentials.kt
+++ b/core/src/commonMain/kotlin/com/powersync/connectors/PowerSyncCredentials.kt
@@ -19,7 +19,12 @@ public data class PowerSyncCredentials(
     /**
      * User ID.
      */
-    @SerialName("user_id") val userId: String?,
+    @Deprecated(
+        message = "This property is no longer used and should be removed.",
+        level = DeprecationLevel.WARNING,
+    )
+    @SerialName("user_id")
+    val userId: String? = null,
 ) {
     override fun toString(): String = "PowerSyncCredentials<endpoint: $endpoint userId: $userId>"
 
diff --git a/core/src/commonMain/kotlin/com/powersync/sync/SyncStream.kt b/core/src/commonMain/kotlin/com/powersync/sync/SyncStream.kt
index 1f6e00d6..56859443 100644
--- a/core/src/commonMain/kotlin/com/powersync/sync/SyncStream.kt
+++ b/core/src/commonMain/kotlin/com/powersync/sync/SyncStream.kt
@@ -174,7 +174,6 @@ internal class SyncStream(
                 contentType(ContentType.Application.Json)
                 headers {
                     append(HttpHeaders.Authorization, "Token ${credentials.token}")
-                    append("User-Id", credentials.userId ?: "")
                 }
             }
         if (response.status.value == 401) {
@@ -202,7 +201,6 @@ internal class SyncStream(
                     contentType(ContentType.Application.Json)
                     headers {
                         append(HttpHeaders.Authorization, "Token ${credentials.token}")
-                        append("User-Id", credentials.userId ?: "")
                     }
                     timeout { socketTimeoutMillis = Long.MAX_VALUE }
                     setBody(bodyJson)
diff --git a/core/src/commonTest/kotlin/com/powersync/TestConnector.kt b/core/src/commonTest/kotlin/com/powersync/TestConnector.kt
index 1319e637..1c59b889 100644
--- a/core/src/commonTest/kotlin/com/powersync/TestConnector.kt
+++ b/core/src/commonTest/kotlin/com/powersync/TestConnector.kt
@@ -7,7 +7,6 @@ class TestConnector : PowerSyncBackendConnector() {
     var fetchCredentialsCallback: suspend () -> PowerSyncCredentials? = {
         PowerSyncCredentials(
             token = "test-token",
-            userId = "test-user",
             endpoint = "https://test.com",
         )
     }
diff --git a/core/src/commonTest/kotlin/com/powersync/sync/SyncStreamTest.kt b/core/src/commonTest/kotlin/com/powersync/sync/SyncStreamTest.kt
index d335b4b4..b9011a46 100644
--- a/core/src/commonTest/kotlin/com/powersync/sync/SyncStreamTest.kt
+++ b/core/src/commonTest/kotlin/com/powersync/sync/SyncStreamTest.kt
@@ -86,7 +86,6 @@ class SyncStreamTest {
                 everySuspend { getCredentialsCached() } returns
                     PowerSyncCredentials(
                         token = "test-token",
-                        userId = "test-user",
                         endpoint = "https://test.com",
                     )
             }