diff --git a/CHANGELOG.md b/CHANGELOG.md
index 72431094bc..33deafe6e7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -24,6 +24,7 @@
 
 ### Internal
 
+- Add integration to track session replay custom masking ([#5088](https://github.com/getsentry/sentry-java/pull/5088))
 - Establish new native exception mechanisms to differentiate events generated by `sentry-native` from `ApplicationExitInfo`. ([#5052](https://github.com/getsentry/sentry-java/pull/5052))
 - Set `write` permission for `statuses` in the changelog preview GHA workflow. ([#5053](https://github.com/getsentry/sentry-java/pull/5053))
 
diff --git a/sentry-android-replay/src/main/java/io/sentry/android/replay/viewhierarchy/ComposeViewHierarchyNode.kt b/sentry-android-replay/src/main/java/io/sentry/android/replay/viewhierarchy/ComposeViewHierarchyNode.kt
index cbcadc0391..dcef27d523 100644
--- a/sentry-android-replay/src/main/java/io/sentry/android/replay/viewhierarchy/ComposeViewHierarchyNode.kt
+++ b/sentry-android-replay/src/main/java/io/sentry/android/replay/viewhierarchy/ComposeViewHierarchyNode.kt
@@ -85,10 +85,12 @@ internal object ComposeViewHierarchyNode {
   ): Boolean {
     val sentryPrivacyModifier = this?.getOrNull(SentryReplayModifiers.SentryPrivacy)
     if (sentryPrivacyModifier == "unmask") {
+      SentryReplayOptions.trackCustomMasking()
       return false
     }
 
     if (sentryPrivacyModifier == "mask") {
+      SentryReplayOptions.trackCustomMasking()
       return true
     }
 
diff --git a/sentry-android-replay/src/main/java/io/sentry/android/replay/viewhierarchy/ViewHierarchyNode.kt b/sentry-android-replay/src/main/java/io/sentry/android/replay/viewhierarchy/ViewHierarchyNode.kt
index 2cde60f4fb..08add79d62 100644
--- a/sentry-android-replay/src/main/java/io/sentry/android/replay/viewhierarchy/ViewHierarchyNode.kt
+++ b/sentry-android-replay/src/main/java/io/sentry/android/replay/viewhierarchy/ViewHierarchyNode.kt
@@ -8,6 +8,7 @@ import android.view.ViewParent
 import android.widget.ImageView
 import android.widget.TextView
 import io.sentry.SentryOptions
+import io.sentry.SentryReplayOptions
 import io.sentry.android.replay.R
 import io.sentry.android.replay.util.AndroidTextLayout
 import io.sentry.android.replay.util.TextLayout
@@ -291,6 +292,7 @@ internal sealed class ViewHierarchyNode(
         (tag as? String)?.lowercase()?.contains(SENTRY_UNMASK_TAG) == true ||
           getTag(R.id.sentry_privacy) == "unmask"
       ) {
+        SentryReplayOptions.trackCustomMasking()
         return false
       }
 
@@ -298,6 +300,7 @@ internal sealed class ViewHierarchyNode(
         (tag as? String)?.lowercase()?.contains(SENTRY_MASK_TAG) == true ||
           getTag(R.id.sentry_privacy) == "mask"
       ) {
+        SentryReplayOptions.trackCustomMasking()
         return true
       }
 
diff --git a/sentry/src/main/java/io/sentry/SentryReplayOptions.java b/sentry/src/main/java/io/sentry/SentryReplayOptions.java
index 367b150c92..c4e112f8b2 100644
--- a/sentry/src/main/java/io/sentry/SentryReplayOptions.java
+++ b/sentry/src/main/java/io/sentry/SentryReplayOptions.java
@@ -1,5 +1,7 @@
 package io.sentry;
 
+import static io.sentry.util.IntegrationUtils.addIntegrationToSdkVersion;
+
 import io.sentry.protocol.SdkVersion;
 import io.sentry.util.SampleRateUtils;
 import java.util.ArrayList;
@@ -13,9 +15,13 @@
 import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
+import org.jetbrains.annotations.TestOnly;
 
 public final class SentryReplayOptions {
 
+  private static final String CUSTOM_MASKING_INTEGRATION_NAME = "ReplayCustomMasking";
+  private static volatile boolean customMaskingTracked = false;
+
   public static final String TEXT_VIEW_CLASS_NAME = "android.widget.TextView";
   public static final String IMAGE_VIEW_CLASS_NAME = "android.widget.ImageView";
   public static final String WEB_VIEW_CLASS_NAME = "android.webkit.WebView";
@@ -209,8 +215,9 @@ public enum SentryReplayQuality {
 
   public SentryReplayOptions(final boolean empty, final @Nullable SdkVersion sdkVersion) {
     if (!empty) {
-      setMaskAllText(true);
-      setMaskAllImages(true);
+      // Add default mask classes directly without setting usingCustomMasking flag
+      maskViewClasses.add(TEXT_VIEW_CLASS_NAME);
+      maskViewClasses.add(IMAGE_VIEW_CLASS_NAME);
       maskViewClasses.add(WEB_VIEW_CLASS_NAME);
       maskViewClasses.add(VIDEO_VIEW_CLASS_NAME);
       maskViewClasses.add(ANDROIDX_MEDIA_VIEW_CLASS_NAME);
@@ -275,11 +282,12 @@ public void setSessionSampleRate(final @Nullable Double sessionSampleRate) {
    * <p>Default is enabled.
    */
   public void setMaskAllText(final boolean maskAllText) {
+    trackCustomMasking();
     if (maskAllText) {
-      addMaskViewClass(TEXT_VIEW_CLASS_NAME);
+      maskViewClasses.add(TEXT_VIEW_CLASS_NAME);
       unmaskViewClasses.remove(TEXT_VIEW_CLASS_NAME);
     } else {
-      addUnmaskViewClass(TEXT_VIEW_CLASS_NAME);
+      unmaskViewClasses.add(TEXT_VIEW_CLASS_NAME);
       maskViewClasses.remove(TEXT_VIEW_CLASS_NAME);
     }
   }
@@ -293,11 +301,12 @@ public void setMaskAllText(final boolean maskAllText) {
    * <p>Default is enabled.
    */
   public void setMaskAllImages(final boolean maskAllImages) {
+    trackCustomMasking();
     if (maskAllImages) {
-      addMaskViewClass(IMAGE_VIEW_CLASS_NAME);
+      maskViewClasses.add(IMAGE_VIEW_CLASS_NAME);
       unmaskViewClasses.remove(IMAGE_VIEW_CLASS_NAME);
     } else {
-      addUnmaskViewClass(IMAGE_VIEW_CLASS_NAME);
+      unmaskViewClasses.add(IMAGE_VIEW_CLASS_NAME);
       maskViewClasses.remove(IMAGE_VIEW_CLASS_NAME);
     }
   }
@@ -308,6 +317,7 @@ public Set<String> getMaskViewClasses() {
   }
 
   public void addMaskViewClass(final @NotNull String className) {
+    trackCustomMasking();
     this.maskViewClasses.add(className);
   }
 
@@ -317,6 +327,7 @@ public Set<String> getUnmaskViewClasses() {
   }
 
   public void addUnmaskViewClass(final @NotNull String className) {
+    trackCustomMasking();
     this.unmaskViewClasses.add(className);
   }
 
@@ -351,7 +362,7 @@ public long getSessionDuration() {
 
   @ApiStatus.Internal
   public void setMaskViewContainerClass(@NotNull String containerClass) {
-    addMaskViewClass(containerClass);
+    maskViewClasses.add(containerClass);
     maskViewContainerClass = containerClass;
   }
 
@@ -370,6 +381,19 @@ public void setUnmaskViewContainerClass(@NotNull String containerClass) {
     return unmaskViewContainerClass;
   }
 
+  @ApiStatus.Internal
+  public static void trackCustomMasking() {
+    if (!customMaskingTracked) {
+      customMaskingTracked = true;
+      addIntegrationToSdkVersion(CUSTOM_MASKING_INTEGRATION_NAME);
+    }
+  }
+
+  @TestOnly
+  public static void resetCustomMaskingTracked() {
+    customMaskingTracked = false;
+  }
+
   @ApiStatus.Internal
   public boolean isTrackConfiguration() {
     return trackConfiguration;
diff --git a/sentry/src/test/java/io/sentry/SentryReplayOptionsTest.kt b/sentry/src/test/java/io/sentry/SentryReplayOptionsTest.kt
index cf96bd5d7d..e1391d0b40 100644
--- a/sentry/src/test/java/io/sentry/SentryReplayOptionsTest.kt
+++ b/sentry/src/test/java/io/sentry/SentryReplayOptionsTest.kt
@@ -1,10 +1,19 @@
 package io.sentry
 
+import kotlin.test.BeforeTest
 import kotlin.test.Test
 import kotlin.test.assertEquals
+import kotlin.test.assertFalse
 import kotlin.test.assertTrue
 
 class SentryReplayOptionsTest {
+
+  @BeforeTest
+  fun setup() {
+    SentryIntegrationPackageStorage.getInstance().clearStorage()
+    SentryReplayOptions.resetCustomMaskingTracked()
+  }
+
   @Test
   fun `uses medium quality as default`() {
     val replayOptions = SentryReplayOptions(true, null)
@@ -126,4 +135,80 @@ class SentryReplayOptionsTest {
     assertTrue(headers.contains("X-Response-Header"))
     assertTrue(headers.contains("X-Debug-Header"))
   }
+
+  // Custom Masking Integration Tests
+
+  private fun hasCustomMaskingIntegration(): Boolean {
+    return SentryIntegrationPackageStorage.getInstance()
+      .integrations
+      .contains("ReplayCustomMasking")
+  }
+
+  @Test
+  fun `default options does not add ReplayCustomMasking integration`() {
+    SentryReplayOptions(false, null)
+    assertFalse(hasCustomMaskingIntegration())
+  }
+
+  @Test
+  fun `empty options does not add ReplayCustomMasking integration`() {
+    SentryReplayOptions(true, null)
+    assertFalse(hasCustomMaskingIntegration())
+  }
+
+  @Test
+  fun `addUnmaskViewClass adds ReplayCustomMasking integration`() {
+    val options = SentryReplayOptions(false, null)
+    options.addUnmaskViewClass("com.example.MyTextView")
+    assertTrue(hasCustomMaskingIntegration())
+  }
+
+  @Test
+  fun `setMaskViewContainerClass does not add ReplayCustomMasking integration`() {
+    val options = SentryReplayOptions(false, null)
+    options.setMaskViewContainerClass("com.example.MyContainer")
+    assertFalse(hasCustomMaskingIntegration())
+  }
+
+  @Test
+  fun `setUnmaskViewContainerClass does not add ReplayCustomMasking integration`() {
+    val options = SentryReplayOptions(false, null)
+    options.setUnmaskViewContainerClass("com.example.MyContainer")
+    assertFalse(hasCustomMaskingIntegration())
+  }
+
+  @Test
+  fun `trackCustomMasking adds ReplayCustomMasking integration`() {
+    SentryReplayOptions.trackCustomMasking()
+    assertTrue(hasCustomMaskingIntegration())
+  }
+
+  @Test
+  fun `trackCustomMasking only adds integration once`() {
+    SentryReplayOptions.trackCustomMasking()
+    SentryReplayOptions.trackCustomMasking()
+    assertTrue(hasCustomMaskingIntegration())
+    assertEquals(1, SentryIntegrationPackageStorage.getInstance().integrations.count { it == "ReplayCustomMasking" })
+  }
+
+  @Test
+  fun `addMaskViewClass adds ReplayCustomMasking integration`() {
+    val options = SentryReplayOptions(false, null)
+    options.addMaskViewClass("com.example.MySensitiveView")
+    assertTrue(hasCustomMaskingIntegration())
+  }
+
+  @Test
+  fun `setMaskAllText adds ReplayCustomMasking integration`() {
+    val options = SentryReplayOptions(false, null)
+    options.setMaskAllText(false)
+    assertTrue(hasCustomMaskingIntegration())
+  }
+
+  @Test
+  fun `setMaskAllImages adds ReplayCustomMasking integration`() {
+    val options = SentryReplayOptions(false, null)
+    options.setMaskAllImages(false)
+    assertTrue(hasCustomMaskingIntegration())
+  }
 }