diff --git a/CHANGELOG.md b/CHANGELOG.md
index b1f667dbf9..c41f6a9dbe 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,7 @@ Docs: https://docs.openclaw.ai
 ### Changes
 
 - Cron/Gateway: separate per-job webhook delivery (`delivery.mode = "webhook"`) from announce delivery, enforce valid HTTP(S) webhook URLs, and keep a temporary legacy `notify + cron.webhook` fallback for stored jobs. (#17901) Thanks @advaitpaliwal.
+- iOS/Talk: add a `Voice Directive Hint` toggle for Talk Mode prompts so users can disable ElevenLabs voice-switching instructions to save tokens when not needed. (#18250) Thanks @zeulewan.
 - Telegram/Agents: add inline button `style` support (`primary|success|danger`) across message tool schema, Telegram action parsing, send pipeline, and runtime prompt guidance. (#18241) Thanks @obviyus.
 
 ### Fixes
diff --git a/apps/ios/Sources/Settings/SettingsTab.swift b/apps/ios/Sources/Settings/SettingsTab.swift
index 0f8e461d7d..31653f1966 100644
--- a/apps/ios/Sources/Settings/SettingsTab.swift
+++ b/apps/ios/Sources/Settings/SettingsTab.swift
@@ -15,6 +15,7 @@ struct SettingsTab: View {
     @AppStorage("voiceWake.enabled") private var voiceWakeEnabled: Bool = false
     @AppStorage("talk.enabled") private var talkEnabled: Bool = false
     @AppStorage("talk.button.enabled") private var talkButtonEnabled: Bool = true
+    @AppStorage("talk.voiceDirectiveHint.enabled") private var talkVoiceDirectiveHintEnabled: Bool = true
     @AppStorage("camera.enabled") private var cameraEnabled: Bool = true
     @AppStorage("location.enabledMode") private var locationEnabledModeRaw: String = OpenClawLocationMode.off.rawValue
     @AppStorage("location.preciseEnabled") private var locationPreciseEnabled: Bool = true
@@ -255,6 +256,10 @@ struct SettingsTab: View {
                         Text("Use this local override when gateway config redacts talk.apiKey for mobile clients.")
                             .font(.footnote)
                             .foregroundStyle(.secondary)
+                        Toggle("Voice Directive Hint", isOn: self.$talkVoiceDirectiveHintEnabled)
+                        Text("Include ElevenLabs voice switching instructions in the Talk Mode prompt. Disable to save tokens.")
+                            .font(.footnote)
+                            .foregroundStyle(.secondary)
                         // Keep this separate so users can hide the side bubble without disabling Talk Mode.
                         Toggle("Show Talk Button", isOn: self.$talkButtonEnabled)
 
diff --git a/apps/ios/Sources/Voice/TalkModeManager.swift b/apps/ios/Sources/Voice/TalkModeManager.swift
index fae5c28be4..10aaad8acb 100644
--- a/apps/ios/Sources/Voice/TalkModeManager.swift
+++ b/apps/ios/Sources/Voice/TalkModeManager.swift
@@ -828,7 +828,11 @@ final class TalkModeManager: NSObject {
     private func buildPrompt(transcript: String) -> String {
         let interrupted = self.lastInterruptedAtSeconds
         self.lastInterruptedAtSeconds = nil
-        return TalkPromptBuilder.build(transcript: transcript, interruptedAtSeconds: interrupted)
+        let includeVoiceDirectiveHint = (UserDefaults.standard.object(forKey: "talk.voiceDirectiveHint.enabled") as? Bool) ?? true
+        return TalkPromptBuilder.build(
+            transcript: transcript,
+            interruptedAtSeconds: interrupted,
+            includeVoiceDirectiveHint: includeVoiceDirectiveHint)
     }
 
     private enum ChatCompletionState: CustomStringConvertible {
diff --git a/apps/shared/OpenClawKit/Sources/OpenClawKit/TalkPromptBuilder.swift b/apps/shared/OpenClawKit/Sources/OpenClawKit/TalkPromptBuilder.swift
index c63f40e9d3..2a2e39d68c 100644
--- a/apps/shared/OpenClawKit/Sources/OpenClawKit/TalkPromptBuilder.swift
+++ b/apps/shared/OpenClawKit/Sources/OpenClawKit/TalkPromptBuilder.swift
@@ -1,10 +1,19 @@
 public enum TalkPromptBuilder: Sendable {
-    public static func build(transcript: String, interruptedAtSeconds: Double?) -> String {
+    public static func build(
+        transcript: String,
+        interruptedAtSeconds: Double?,
+        includeVoiceDirectiveHint: Bool = true
+    ) -> String {
         var lines: [String] = [
             "Talk Mode active. Reply in a concise, spoken tone.",
-            "You may optionally prefix the response with JSON (first line) to set ElevenLabs voice (id or alias), e.g. {\"voice\":\"<id>\",\"once\":true}.",
         ]
 
+        if includeVoiceDirectiveHint {
+            lines.append(
+                "You may optionally prefix the response with JSON (first line) to set ElevenLabs voice (id or alias), e.g. {\"voice\":\"<id>\",\"once\":true}."
+            )
+        }
+
         if let interruptedAtSeconds {
             let formatted = String(format: "%.1f", interruptedAtSeconds)
             lines.append("Assistant speech interrupted at \(formatted)s.")
diff --git a/apps/shared/OpenClawKit/Tests/OpenClawKitTests/TalkPromptBuilderTests.swift b/apps/shared/OpenClawKit/Tests/OpenClawKitTests/TalkPromptBuilderTests.swift
index 1ca18fdf32..513b60d047 100644
--- a/apps/shared/OpenClawKit/Tests/OpenClawKitTests/TalkPromptBuilderTests.swift
+++ b/apps/shared/OpenClawKit/Tests/OpenClawKitTests/TalkPromptBuilderTests.swift
@@ -12,4 +12,18 @@ final class TalkPromptBuilderTests: XCTestCase {
         let prompt = TalkPromptBuilder.build(transcript: "Hi", interruptedAtSeconds: 1.234)
         XCTAssertTrue(prompt.contains("Assistant speech interrupted at 1.2s."))
     }
+
+    func testBuildIncludesVoiceDirectiveHintByDefault() {
+        let prompt = TalkPromptBuilder.build(transcript: "Hello", interruptedAtSeconds: nil)
+        XCTAssertTrue(prompt.contains("ElevenLabs voice"))
+    }
+
+    func testBuildExcludesVoiceDirectiveHintWhenDisabled() {
+        let prompt = TalkPromptBuilder.build(
+            transcript: "Hello",
+            interruptedAtSeconds: nil,
+            includeVoiceDirectiveHint: false)
+        XCTAssertFalse(prompt.contains("ElevenLabs voice"))
+        XCTAssertTrue(prompt.contains("Talk Mode active."))
+    }
 }