diff --git a/CHANGELOG.md b/CHANGELOG.md
index b738c2a..6097d07 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,7 @@
 
 ### Advanced IMCore
 - fix: defer injected bridge bootstrap until after Messages startup so macOS 26 dyld constructor ordering cannot touch ObjC/Foundation/IMCore before the process is ready (#138, thanks @omarshahine).
+- fix: let bridge-backed sends and initial chat creation wait longer for slow Messages private-send completions while keeping short timeouts for probe and mutation calls (#139, thanks @omarshahine).
 
 ## 0.11.0 - 2026-05-31
 
diff --git a/Sources/IMsgCore/IMsgBridgeClient.swift b/Sources/IMsgCore/IMsgBridgeClient.swift
index 789948d..10dc261 100644
--- a/Sources/IMsgCore/IMsgBridgeClient.swift
+++ b/Sources/IMsgCore/IMsgBridgeClient.swift
@@ -38,14 +38,28 @@ public final class IMsgBridgeClient: @unchecked Sendable {
   /// Invoke a v2 bridge action and return its `data` payload on success.
   /// Legacy single-file IPC is only used when explicitly requested through
   /// `IMSG_BRIDGE_LEGACY_IPC=1`.
+  public func invoke(
+    action: BridgeAction,
+    params: [String: Any] = [:]
+  ) async throws -> [String: Any] {
+    try await invoke(
+      action: action,
+      params: params,
+      timeout: IMsgBridgeProtocol.defaultResponseTimeout(for: action)
+    )
+  }
+
+  /// Invoke a v2 bridge action with an explicit timeout.
+  /// Legacy single-file IPC is only used when explicitly requested through
+  /// `IMSG_BRIDGE_LEGACY_IPC=1`.
   public func invoke(
     action: BridgeAction,
     params: [String: Any] = [:],
-    timeout: TimeInterval = IMsgBridgeProtocol.defaultResponseTimeout
+    timeout: TimeInterval
   ) async throws -> [String: Any] {
     if useLegacyIPC {
       try launcher.ensureRunning()
-      return try await invokeLegacy(action: action, params: params)
+      return try await invokeLegacy(action: action, params: params, timeout: timeout)
     }
 
     try launcher.ensureLaunched()
@@ -111,10 +125,15 @@ public final class IMsgBridgeClient: @unchecked Sendable {
 
   private func invokeLegacy(
     action: BridgeAction,
-    params: [String: Any]
+    params: [String: Any],
+    timeout: TimeInterval
   ) async throws -> [String: Any] {
     do {
-      let raw = try await launcher.sendCommand(action: action.rawValue, params: params)
+      let raw = try await launcher.sendCommand(
+        action: action.rawValue,
+        params: params,
+        timeout: timeout
+      )
       let response = try BridgeResponse.parse(raw)
       if response.success {
         return response.data
diff --git a/Sources/IMsgCore/IMsgBridgeProtocol.swift b/Sources/IMsgCore/IMsgBridgeProtocol.swift
index 1bb06ea..5c3a39c 100644
--- a/Sources/IMsgCore/IMsgBridgeProtocol.swift
+++ b/Sources/IMsgCore/IMsgBridgeProtocol.swift
@@ -22,8 +22,22 @@ public enum IMsgBridgeProtocol {
   public static let rotatedEventsFileName: String = ".imsg-events.jsonl.1"
   public static let eventsRotationBytes: Int = 1 * 1024 * 1024
 
-  /// Default per-request timeout for synchronous RPC waits.
+  /// Default per-request timeout for synchronous non-send RPC waits.
   public static let defaultResponseTimeout: TimeInterval = 10.0
+
+  /// Default timeout for send-style bridge waits. macOS 26 private sends can
+  /// stall for well over the probe window before Messages.app returns.
+  public static let defaultSendResponseTimeout: TimeInterval = 150.0
+
+  public static func defaultResponseTimeout(for action: BridgeAction) -> TimeInterval {
+    switch action {
+    case .sendMessage, .sendMultipart, .sendAttachment, .sendPoll, .sendReaction,
+      .createChat:
+      return defaultSendResponseTimeout
+    default:
+      return defaultResponseTimeout
+    }
+  }
 }
 
 /// All action verbs exposed by the v2 bridge. Names match the BlueBubbles
diff --git a/Sources/IMsgCore/MessagesLauncher.swift b/Sources/IMsgCore/MessagesLauncher.swift
index a5ef635..beb11bb 100644
--- a/Sources/IMsgCore/MessagesLauncher.swift
+++ b/Sources/IMsgCore/MessagesLauncher.swift
@@ -72,7 +72,11 @@ import Foundation
         return false
       }
       do {
-        let response = try sendCommandSync(action: "ping", params: [:])
+        let response = try sendCommandSync(
+          action: "ping",
+          params: [:],
+          timeout: IMsgBridgeProtocol.defaultResponseTimeout
+        )
         return response["success"] as? Bool == true
       } catch {
         return false
@@ -171,6 +175,17 @@ import Foundation
     /// Send a command asynchronously.
     public func sendCommand(
       action: String, params: [String: Any]
+    ) async throws -> [String: Any] {
+      try await sendCommand(
+        action: action,
+        params: params,
+        timeout: IMsgBridgeProtocol.defaultResponseTimeout
+      )
+    }
+
+    /// Send a command asynchronously with an explicit response timeout.
+    public func sendCommand(
+      action: String, params: [String: Any], timeout: TimeInterval
     ) async throws -> [String: Any] {
       try ensureRunning()
       // Serialize params to JSON data to cross the Sendable boundary safely
@@ -182,7 +197,11 @@ import Foundation
             let deserializedParams =
               (try? JSONSerialization.jsonObject(with: paramsData, options: []))
               as? [String: Any] ?? [:]
-            let response = try self.sendCommandSync(action: action, params: deserializedParams)
+            let response = try self.sendCommandSync(
+              action: action,
+              params: deserializedParams,
+              timeout: timeout
+            )
             continuation.resume(returning: response)
           } catch {
             continuation.resume(throwing: error)
@@ -273,7 +292,7 @@ import Foundation
     }
 
     private func sendCommandSync(
-      action: String, params: [String: Any]
+      action: String, params: [String: Any], timeout: TimeInterval
     ) throws -> [String: Any] {
       lock.lock()
       defer { lock.unlock() }
@@ -287,7 +306,7 @@ import Foundation
       let jsonData = try JSONSerialization.data(withJSONObject: command, options: [])
       try jsonData.write(to: URL(fileURLWithPath: commandFile))
 
-      let deadline = Date().addingTimeInterval(10.0)
+      let deadline = Date().addingTimeInterval(timeout)
       while Date() < deadline {
         Thread.sleep(forTimeInterval: 0.05)
 
@@ -342,8 +361,19 @@ import Foundation
     public func killMessages() {}
 
     public func sendCommand(action: String, params: [String: Any]) async throws -> [String: Any] {
+      try await sendCommand(
+        action: action,
+        params: params,
+        timeout: IMsgBridgeProtocol.defaultResponseTimeout
+      )
+    }
+
+    public func sendCommand(
+      action: String, params: [String: Any], timeout: TimeInterval
+    ) async throws -> [String: Any] {
       _ = action
       _ = params
+      _ = timeout
       throw MessagesLauncherError.launchFailed("Messages.app is only available on macOS.")
     }
 
diff --git a/Tests/IMsgCoreTests/IMsgBridgeProtocolTests.swift b/Tests/IMsgCoreTests/IMsgBridgeProtocolTests.swift
index 171cb85..3c8f064 100644
--- a/Tests/IMsgCoreTests/IMsgBridgeProtocolTests.swift
+++ b/Tests/IMsgCoreTests/IMsgBridgeProtocolTests.swift
@@ -1,3 +1,4 @@
+import Foundation
 import Testing
 
 @testable import IMsgCore
@@ -82,4 +83,60 @@ struct IMsgBridgeProtocolTests {
     #expect(response.success == false)
     #expect(response.error == "Chat not found")
   }
+
+  @Test
+  func bridgeProtocolUsesLongerDefaultForSendActions() {
+    #expect(IMsgBridgeProtocol.defaultResponseTimeout == 10.0)
+    #expect(IMsgBridgeProtocol.defaultSendResponseTimeout == 150.0)
+
+    for action in [
+      BridgeAction.sendMessage,
+      .sendMultipart,
+      .sendAttachment,
+      .sendPoll,
+      .sendReaction,
+      .createChat,
+    ] {
+      #expect(
+        IMsgBridgeProtocol.defaultResponseTimeout(for: action)
+          == IMsgBridgeProtocol.defaultSendResponseTimeout
+      )
+    }
+  }
+
+  @Test
+  func bridgeProtocolKeepsShortDefaultForNonSendActions() {
+    for action in [
+      BridgeAction.status,
+      .typing,
+      .read,
+      .editMessage,
+      .unsendMessage,
+      .deleteMessage,
+      .notifyAnyways,
+    ] {
+      #expect(
+        IMsgBridgeProtocol.defaultResponseTimeout(for: action)
+          == IMsgBridgeProtocol.defaultResponseTimeout
+      )
+    }
+  }
+
+  @Test
+  func bridgeClientKeepsExplicitTimeoutInvokeSignature() {
+    let explicitTimeoutInvoke:
+      (BridgeAction, [String: Any], TimeInterval) async throws -> [String: Any] =
+        IMsgBridgeClient.shared.invoke
+    _ = explicitTimeoutInvoke
+  }
+
+  @Test
+  func messagesLauncherKeepsLegacyCommandSignatureAndAllowsExplicitTimeout() {
+    let defaultTimeoutSend: (String, [String: Any]) async throws -> [String: Any] =
+      MessagesLauncher.shared.sendCommand
+    let explicitTimeoutSend: (String, [String: Any], TimeInterval) async throws -> [String: Any] =
+      MessagesLauncher.shared.sendCommand
+    _ = defaultTimeoutSend
+    _ = explicitTimeoutSend
+  }
 }