diff --git a/chrome/browser/content_settings/one_time_permission_provider.cc b/chrome/browser/content_settings/one_time_permission_provider.cc
index 4ff07c2c5cffe6..11027aff927fd0 100644
--- a/chrome/browser/content_settings/one_time_permission_provider.cc
+++ b/chrome/browser/content_settings/one_time_permission_provider.cc
@@ -15,6 +15,7 @@
 #include "chrome/browser/permissions/one_time_permissions_tracker_factory.h"
 #include "components/content_settings/core/browser/content_settings_rule.h"
 #include "components/content_settings/core/common/content_settings_utils.h"
+#include "components/permissions/permission_uma_util.h"
 #include "components/permissions/permission_util.h"
 #include "url/gurl.h"
 
@@ -53,6 +54,11 @@ bool OneTimePermissionProvider::SetWebsiteSetting(
   if (constraints.session_model != content_settings::SessionModel::OneTime) {
     value_map_.DeleteValue(primary_pattern, secondary_pattern,
                            content_settings_type);
+
+    permissions::PermissionUmaUtil::RecordOneTimePermissionEvent(
+        content_settings_type,
+        permissions::OneTimePermissionEvent::REVOKED_MANUALLY);
+
     return false;
   }
   DCHECK_EQ(content_settings::ValueToContentSetting(value),
@@ -66,6 +72,10 @@ bool OneTimePermissionProvider::SetWebsiteSetting(
           .session_model = content_settings::SessionModel::OneTime,
       });
 
+  permissions::PermissionUmaUtil::RecordOneTimePermissionEvent(
+      content_settings_type,
+      permissions::OneTimePermissionEvent::GRANTED_ONE_TIME);
+
   // We need to handle transitions from Allow to Allow Once gracefully.
   // In that case we add the Allow Once setting in this provider, but also
   // have to clear the Allow setting in the pref provider. By returning false
@@ -112,7 +122,9 @@ void OneTimePermissionProvider::OnLastPageFromOriginClosed(
   for (auto setting_type : {ContentSettingsType::GEOLOCATION,
                             ContentSettingsType::MEDIASTREAM_CAMERA,
                             ContentSettingsType::MEDIASTREAM_MIC}) {
-    DeleteValuesMatchingGurl(setting_type, origin.GetURL());
+    DeleteValuesMatchingGurl(
+        setting_type, origin.GetURL(),
+        permissions::OneTimePermissionEvent::ALL_TABS_CLOSED_OR_DISCARDED);
   }
 }
 
@@ -122,7 +134,9 @@ void OneTimePermissionProvider::OnLastPageFromOriginClosed(
 // origin.
 void OneTimePermissionProvider::OnAllTabsInBackgroundTimerExpired(
     const url::Origin& origin) {
-  DeleteValuesMatchingGurl(ContentSettingsType::GEOLOCATION, origin.GetURL());
+  DeleteValuesMatchingGurl(
+      ContentSettingsType::GEOLOCATION, origin.GetURL(),
+      permissions::OneTimePermissionEvent::EXPIRED_IN_BACKGROUND);
 }
 
 // All tabs to the origin have not shown a tab indicator for video for a certain
@@ -130,8 +144,9 @@ void OneTimePermissionProvider::OnAllTabsInBackgroundTimerExpired(
 // associated with the origin.
 void OneTimePermissionProvider::OnCapturingVideoExpired(
     const url::Origin& origin) {
-  DeleteValuesMatchingGurl(ContentSettingsType::MEDIASTREAM_CAMERA,
-                           origin.GetURL());
+  DeleteValuesMatchingGurl(
+      ContentSettingsType::MEDIASTREAM_CAMERA, origin.GetURL(),
+      permissions::OneTimePermissionEvent::EXPIRED_IN_BACKGROUND);
 }
 
 // All tabs to the origin have not shown a tab indicator for microphone access
@@ -139,13 +154,15 @@ void OneTimePermissionProvider::OnCapturingVideoExpired(
 // permission associated with the origin.
 void OneTimePermissionProvider::OnCapturingAudioExpired(
     const url::Origin& origin) {
-  DeleteValuesMatchingGurl(ContentSettingsType::MEDIASTREAM_MIC,
-                           origin.GetURL());
+  DeleteValuesMatchingGurl(
+      ContentSettingsType::MEDIASTREAM_MIC, origin.GetURL(),
+      permissions::OneTimePermissionEvent::EXPIRED_IN_BACKGROUND);
 }
 
 void OneTimePermissionProvider::DeleteValuesMatchingGurl(
     ContentSettingsType content_setting_type,
-    const GURL& origin_gurl) {
+    const GURL& origin_gurl,
+    permissions::OneTimePermissionEvent trigger_event) {
   std::set<content_settings::OriginIdentifierValueMap::PatternPair>
       patterns_to_delete;
   std::unique_ptr<content_settings::RuleIterator> rule_iterator(
@@ -156,6 +173,10 @@ void OneTimePermissionProvider::DeleteValuesMatchingGurl(
     if (rule.primary_pattern.Matches(origin_gurl) &&
         rule.secondary_pattern.Matches(origin_gurl)) {
       patterns_to_delete.insert({rule.primary_pattern, rule.secondary_pattern});
+      if (rule.metadata.expiration >= clock_->Now()) {
+        permissions::PermissionUmaUtil::RecordOneTimePermissionEvent(
+            content_setting_type, trigger_event);
+      }
     }
   }
   rule_iterator.reset();
diff --git a/chrome/browser/content_settings/one_time_permission_provider.h b/chrome/browser/content_settings/one_time_permission_provider.h
index 09f01a84c7e6df..bb0c126682e328 100644
--- a/chrome/browser/content_settings/one_time_permission_provider.h
+++ b/chrome/browser/content_settings/one_time_permission_provider.h
@@ -14,6 +14,7 @@
 #include "components/content_settings/core/browser/content_settings_origin_identifier_value_map.h"
 #include "components/content_settings/core/browser/user_modifiable_provider.h"
 #include "components/content_settings/core/common/content_settings_pattern.h"
+#include "components/permissions/permission_uma_util.h"
 
 class OneTimePermissionsTracker;
 
@@ -72,8 +73,11 @@ class OneTimePermissionProvider
   void OnShutdown() override;
 
  private:
-  void DeleteValuesMatchingGurl(ContentSettingsType content_setting_type,
-                                const GURL& origin_gurl);
+  // Deletes the matching values and records matching UMA events.
+  void DeleteValuesMatchingGurl(
+      ContentSettingsType content_setting_type,
+      const GURL& origin_gurl,
+      permissions::OneTimePermissionEvent trigger_event);
 
   content_settings::OriginIdentifierValueMap value_map_;
   raw_ptr<OneTimePermissionsTracker> one_time_permissions_tracker_ = nullptr;
diff --git a/chrome/browser/content_settings/one_time_permission_provider_unittest.cc b/chrome/browser/content_settings/one_time_permission_provider_unittest.cc
index 727cfbe2396066..29c8b57a03a0de 100644
--- a/chrome/browser/content_settings/one_time_permission_provider_unittest.cc
+++ b/chrome/browser/content_settings/one_time_permission_provider_unittest.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/content_settings/one_time_permission_provider.h"
 #include <memory>
+#include "base/test/metrics/histogram_tester.h"
 #include "base/test/scoped_feature_list.h"
 #include "base/time/time.h"
 #include "base/values.h"
@@ -50,6 +51,23 @@ class OneTimePermissionProviderTest : public testing::Test {
         .session_model = content_settings::SessionModel::OneTime};
   }
 
+  // TODO(fjacky): extract to utility class crbug.com/1439219
+  // Utility method, because uma mapping functions aren't exposed
+  std::string GetOneTimePermissionEventHistogram(ContentSettingsType type) {
+    std::string permission_type;
+    if (type == ContentSettingsType::GEOLOCATION) {
+      permission_type = "Geolocation";
+    } else if (type == ContentSettingsType::MEDIASTREAM_MIC) {
+      permission_type = "AudioCapture";
+    } else if (type == ContentSettingsType::MEDIASTREAM_CAMERA) {
+      permission_type = "VideoCapture";
+    } else {
+      NOTREACHED();
+    }
+
+    return "Permissions.OneTimePermission." + permission_type + ".Event";
+  }
+
   GURL primary_url = GURL("http://example.com/");
   ContentSettingsPattern primary_pattern =
       ContentSettingsPattern::FromURLNoWildcard(primary_url);
@@ -69,6 +87,7 @@ class OneTimePermissionProviderTest : public testing::Test {
 };
 
 TEST_F(OneTimePermissionProviderTest, SetAndGetContentSetting) {
+  base::HistogramTester histograms;
   EXPECT_EQ(CONTENT_SETTING_DEFAULT,
             TestUtils::GetContentSetting(
                 one_time_permission_provider_.get(), primary_url, secondary_url,
@@ -83,6 +102,12 @@ TEST_F(OneTimePermissionProviderTest, SetAndGetContentSetting) {
             TestUtils::GetContentSetting(
                 one_time_permission_provider_.get(), primary_url, secondary_url,
                 ContentSettingsType::GEOLOCATION, false));
+
+  histograms.ExpectUniqueSample(
+      GetOneTimePermissionEventHistogram(ContentSettingsType::GEOLOCATION),
+      static_cast<base::HistogramBase::Sample>(
+          permissions::OneTimePermissionEvent::GRANTED_ONE_TIME),
+      1);
 }
 
 TEST_F(OneTimePermissionProviderTest,
@@ -122,6 +147,7 @@ TEST_F(OneTimePermissionProviderTest,
 
 TEST_F(OneTimePermissionProviderTest,
        AllTabsInBackgroundExpiryRevokesGeolocation) {
+  base::HistogramTester histograms;
   EXPECT_EQ(CONTENT_SETTING_DEFAULT,
             TestUtils::GetContentSetting(
                 one_time_permission_provider_.get(), primary_url, secondary_url,
@@ -149,14 +175,24 @@ TEST_F(OneTimePermissionProviderTest,
             TestUtils::GetContentSetting(
                 one_time_permission_provider_.get(), other_url, secondary_url,
                 ContentSettingsType::GEOLOCATION, false));
+
+  // We granted to two distinct origins
+  histograms.ExpectBucketCount(
+      GetOneTimePermissionEventHistogram(ContentSettingsType::GEOLOCATION),
+      static_cast<base::HistogramBase::Sample>(
+          permissions::OneTimePermissionEvent::GRANTED_ONE_TIME),
+      2);
+
+  // Only one origin was in the background and should have been expired
+  histograms.ExpectBucketCount(
+      GetOneTimePermissionEventHistogram(ContentSettingsType::GEOLOCATION),
+      static_cast<base::HistogramBase::Sample>(
+          permissions::OneTimePermissionEvent::EXPIRED_IN_BACKGROUND),
+      1);
 }
 
 TEST_F(OneTimePermissionProviderTest, CaptureExpiryRevokesPermissions) {
-  EXPECT_EQ(CONTENT_SETTING_DEFAULT,
-            TestUtils::GetContentSetting(
-                one_time_permission_provider_.get(), primary_url, secondary_url,
-                ContentSettingsType::GEOLOCATION, false));
-
+  base::HistogramTester histograms;
   one_time_permission_provider_->SetWebsiteSetting(
       primary_pattern, ContentSettingsPattern::Wildcard(),
       ContentSettingsType::MEDIASTREAM_CAMERA,
@@ -181,6 +217,35 @@ TEST_F(OneTimePermissionProviderTest, CaptureExpiryRevokesPermissions) {
             TestUtils::GetContentSetting(
                 one_time_permission_provider_.get(), other_url, secondary_url,
                 ContentSettingsType::MEDIASTREAM_MIC, false));
+
+  histograms.ExpectTotalCount(GetOneTimePermissionEventHistogram(
+                                  ContentSettingsType::MEDIASTREAM_CAMERA),
+                              2);
+  histograms.ExpectTotalCount(
+      GetOneTimePermissionEventHistogram(ContentSettingsType::MEDIASTREAM_MIC),
+      2);
+  histograms.ExpectBucketCount(
+      GetOneTimePermissionEventHistogram(
+          ContentSettingsType::MEDIASTREAM_CAMERA),
+      static_cast<base::HistogramBase::Sample>(
+          permissions::OneTimePermissionEvent::GRANTED_ONE_TIME),
+      1);
+  histograms.ExpectBucketCount(
+      GetOneTimePermissionEventHistogram(
+          ContentSettingsType::MEDIASTREAM_CAMERA),
+      static_cast<base::HistogramBase::Sample>(
+          permissions::OneTimePermissionEvent::EXPIRED_IN_BACKGROUND),
+      1);
+  histograms.ExpectBucketCount(
+      GetOneTimePermissionEventHistogram(ContentSettingsType::MEDIASTREAM_MIC),
+      static_cast<base::HistogramBase::Sample>(
+          permissions::OneTimePermissionEvent::GRANTED_ONE_TIME),
+      1);
+  histograms.ExpectBucketCount(
+      GetOneTimePermissionEventHistogram(ContentSettingsType::MEDIASTREAM_MIC),
+      static_cast<base::HistogramBase::Sample>(
+          permissions::OneTimePermissionEvent::EXPIRED_IN_BACKGROUND),
+      1);
 }
 
 TEST_F(OneTimePermissionProviderTest,
@@ -219,6 +284,7 @@ TEST_F(OneTimePermissionProviderTest,
 }
 
 TEST_F(OneTimePermissionProviderTest, EnsureOneDayExpiry) {
+  base::HistogramTester histograms;
   EXPECT_EQ(CONTENT_SETTING_DEFAULT,
             TestUtils::GetContentSetting(
                 one_time_permission_provider_.get(), primary_url, secondary_url,
@@ -235,5 +301,44 @@ TEST_F(OneTimePermissionProviderTest, EnsureOneDayExpiry) {
             TestUtils::GetContentSetting(
                 one_time_permission_provider_.get(), primary_url, secondary_url,
                 ContentSettingsType::GEOLOCATION, false));
+
+  // Only a grant sample should be recorded. 1-day expiry can be computed from
+  // #grants - #other buckets
+  histograms.ExpectUniqueSample(
+      GetOneTimePermissionEventHistogram(ContentSettingsType::GEOLOCATION),
+      static_cast<base::HistogramBase::Sample>(
+          permissions::OneTimePermissionEvent::GRANTED_ONE_TIME),
+      1);
+}
+
+TEST_F(OneTimePermissionProviderTest, ManualRevocationUmaTest) {
+  base::HistogramTester histograms;
+  EXPECT_EQ(CONTENT_SETTING_DEFAULT,
+            TestUtils::GetContentSetting(
+                one_time_permission_provider_.get(), primary_url, secondary_url,
+                ContentSettingsType::GEOLOCATION, false));
+
+  one_time_permission_provider_->SetWebsiteSetting(
+      primary_pattern, ContentSettingsPattern::Wildcard(),
+      ContentSettingsType::GEOLOCATION, base::Value(CONTENT_SETTING_ALLOW),
+      one_time_constraints());
+
+  one_time_permission_provider_->SetWebsiteSetting(
+      primary_pattern, ContentSettingsPattern::Wildcard(),
+      ContentSettingsType::GEOLOCATION, base::Value(CONTENT_SETTING_ASK), {});
+
+  histograms.ExpectTotalCount(
+      GetOneTimePermissionEventHistogram(ContentSettingsType::GEOLOCATION), 2);
+  histograms.ExpectBucketCount(
+      GetOneTimePermissionEventHistogram(ContentSettingsType::GEOLOCATION),
+      static_cast<base::HistogramBase::Sample>(
+          permissions::OneTimePermissionEvent::GRANTED_ONE_TIME),
+      1);
+
+  histograms.ExpectBucketCount(
+      GetOneTimePermissionEventHistogram(ContentSettingsType::GEOLOCATION),
+      static_cast<base::HistogramBase::Sample>(
+          permissions::OneTimePermissionEvent::REVOKED_MANUALLY),
+      1);
 }
 }  // namespace content_settings
diff --git a/chrome/browser/ui/views/permissions/one_time_permission_interactive_ui_test.cc b/chrome/browser/ui/views/permissions/one_time_permission_interactive_ui_test.cc
index 8caa656ddf855a..d2a426e3f73577 100644
--- a/chrome/browser/ui/views/permissions/one_time_permission_interactive_ui_test.cc
+++ b/chrome/browser/ui/views/permissions/one_time_permission_interactive_ui_test.cc
@@ -25,6 +25,7 @@
 #include "chrome/test/base/test_switches.h"
 #include "chrome/test/base/ui_test_utils.h"
 #include "components/content_settings/core/common/content_settings.h"
+#include "components/content_settings/core/common/content_settings_types.h"
 #include "components/performance_manager/public/performance_manager.h"
 #include "components/permissions/features.h"
 #include "components/permissions/permission_request_manager.h"
@@ -216,11 +217,46 @@ class OneTimePermissionInteractiveUiTest : public WebRtcTestBase {
   }
 
  protected:
+  void OtpEventExpectUniqueSample(ContentSettingsType content_setting_type,
+                                  permissions::OneTimePermissionEvent event,
+                                  int occ) {
+    histograms_.ExpectUniqueSample(
+        GetOneTimePermissionEventHistogram(content_setting_type),
+        static_cast<base::HistogramBase::Sample>(event), occ);
+  }
+
+  void OtpEventExpectBucketCount(ContentSettingsType content_setting_type,
+                                 permissions::OneTimePermissionEvent event,
+                                 int occ) {
+    histograms_.ExpectBucketCount(
+        GetOneTimePermissionEventHistogram(content_setting_type),
+        static_cast<base::HistogramBase::Sample>(event), occ);
+  }
+
   std::unique_ptr<device::ScopedGeolocationOverrider> geolocation_overrider_;
 
   raw_ptr<Browser, DanglingUntriaged> current_browser_ = nullptr;
 
+  base::HistogramTester histograms_;
+
  private:
+  // TODO(fjacky): extract to utility class crbug.com/1439219
+  // Utility method, because uma mapping functions aren't exposed
+  std::string GetOneTimePermissionEventHistogram(ContentSettingsType type) {
+    std::string permission_type;
+    if (type == ContentSettingsType::GEOLOCATION) {
+      permission_type = "Geolocation";
+    } else if (type == ContentSettingsType::MEDIASTREAM_MIC) {
+      permission_type = "AudioCapture";
+    } else if (type == ContentSettingsType::MEDIASTREAM_CAMERA) {
+      permission_type = "VideoCapture";
+    } else {
+      NOTREACHED();
+    }
+
+    return "Permissions.OneTimePermission." + permission_type + ".Event";
+  }
+
   // The render frame host where JS calls will be executed.
   raw_ptr<content::RenderFrameHost, DanglingUntriaged> render_frame_host_ =
       nullptr;
@@ -244,6 +280,11 @@ IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
   // Ensure position is accessible in new tab without prompt.
   WatchPositionAndExpectGrantedPermission(
       permissions::PermissionRequestManager::ACCEPT_ONCE, false);
+
+  // Ensure grant event is recorded
+  OtpEventExpectUniqueSample(
+      ContentSettingsType::GEOLOCATION,
+      permissions::OneTimePermissionEvent::GRANTED_ONE_TIME, 1);
 }
 
 IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
@@ -262,6 +303,11 @@ IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
   // Ensure position is accessible in new tab without prompt.
   WatchPositionAndExpectGrantedPermission(
       permissions::PermissionRequestManager::ACCEPT_ONCE, false);
+
+  // Ensure grant event is only recorded once
+  OtpEventExpectUniqueSample(
+      ContentSettingsType::GEOLOCATION,
+      permissions::OneTimePermissionEvent::GRANTED_ONE_TIME, 1);
 }
 
 IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
@@ -279,7 +325,17 @@ IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
 
   // Ensure that a prompt is triggered.
   WatchPositionAndExpectGrantedPermission(
-      permissions::PermissionRequestManager::ACCEPT_ONCE, true);
+      permissions::PermissionRequestManager::ACCEPT_ALL, true);
+
+  // Since the second request was resolved with a persistent accept, only one
+  // otp-grant event should be recorded
+  OtpEventExpectBucketCount(
+      ContentSettingsType::GEOLOCATION,
+      permissions::OneTimePermissionEvent::GRANTED_ONE_TIME, 1);
+
+  OtpEventExpectBucketCount(
+      ContentSettingsType::GEOLOCATION,
+      permissions::OneTimePermissionEvent::ALL_TABS_CLOSED_OR_DISCARDED, 1);
 }
 
 IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
@@ -305,7 +361,17 @@ IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
   // Ensure that a prompt is triggered again when requesting geolocation
   // permission.
   WatchPositionAndExpectGrantedPermission(
-      permissions::PermissionRequestManager::ACCEPT_ONCE, true);
+      permissions::PermissionRequestManager::ACCEPT_ALL, true);
+
+  // Since the second request was resolved with a persistent accept, only one
+  // otp-grant event should be recorded
+  OtpEventExpectBucketCount(
+      ContentSettingsType::GEOLOCATION,
+      permissions::OneTimePermissionEvent::GRANTED_ONE_TIME, 1);
+
+  OtpEventExpectBucketCount(
+      ContentSettingsType::GEOLOCATION,
+      permissions::OneTimePermissionEvent::ALL_TABS_CLOSED_OR_DISCARDED, 1);
 }
 
 IN_PROC_BROWSER_TEST_F(
@@ -336,6 +402,11 @@ IN_PROC_BROWSER_TEST_F(
   // Request geolocation permission and ensure that no prompt is triggered.
   WatchPositionAndExpectGrantedPermission(
       permissions::PermissionRequestManager::ACCEPT_ONCE, false);
+
+  // Ensure that only a single GRANTED_ONE_TIME event is recorded
+  OtpEventExpectUniqueSample(
+      ContentSettingsType::GEOLOCATION,
+      permissions::OneTimePermissionEvent::GRANTED_ONE_TIME, 1);
 }
 
 IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
@@ -364,6 +435,14 @@ IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
   // Ensure that a prompt is triggered again when requesting permission
   WatchPositionAndExpectGrantedPermission(
       permissions::PermissionRequestManager::ACCEPT_ONCE, true);
+
+  OtpEventExpectBucketCount(
+      ContentSettingsType::GEOLOCATION,
+      permissions::OneTimePermissionEvent::GRANTED_ONE_TIME, 2);
+
+  OtpEventExpectBucketCount(
+      ContentSettingsType::GEOLOCATION,
+      permissions::OneTimePermissionEvent::EXPIRED_IN_BACKGROUND, 1);
 }
 
 IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
@@ -378,14 +457,22 @@ IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
   // web contents).
   CloseLastLocalStreamAt(0);
 
-  // Fire running timers. This means, that all one time permission expiration
-  // timers that are running at this point in time will fire their callbacks and
-  // are stopped.
+  // Fire running timers. This means, that all one time permission
+  // expiration timers that are running at this point in time will fire
+  // their callbacks and are stopped.
   FireRunningExpirationTimers();
 
   // Request cam/mic permission, expect no prompt is triggered.
   GetUserMediaAndExpectGrantedPermission(
       permissions::PermissionRequestManager::ACCEPT_ONCE, false, 0);
+
+  // Ensure that only a single GRANTED_ONE_TIME event is recorded per permission
+  OtpEventExpectUniqueSample(
+      ContentSettingsType::MEDIASTREAM_MIC,
+      permissions::OneTimePermissionEvent::GRANTED_ONE_TIME, 1);
+  OtpEventExpectUniqueSample(
+      ContentSettingsType::MEDIASTREAM_CAMERA,
+      permissions::OneTimePermissionEvent::GRANTED_ONE_TIME, 1);
 }
 
 IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
@@ -403,9 +490,9 @@ IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
   // within specified web contents).
   CloseLastLocalStreamAt(0);
 
-  // Fire running timers. This means, that all one time permission expiration
-  // timers that are running at this point in time will fire their callbacks and
-  // are stopped.
+  // Fire running timers. This means, that all one time permission
+  // expiration timers that are running at this point in time will fire
+  // their callbacks and are stopped.
   FireRunningExpirationTimers();
 
   // Switch back to previous tab
@@ -414,6 +501,21 @@ IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
   // Request cam/mic permission, expect a prompt is triggered.
   GetUserMediaAndExpectGrantedPermission(
       permissions::PermissionRequestManager::ACCEPT_ONCE, true, 0);
+
+  OtpEventExpectBucketCount(
+      ContentSettingsType::MEDIASTREAM_MIC,
+      permissions::OneTimePermissionEvent::GRANTED_ONE_TIME, 2);
+
+  OtpEventExpectBucketCount(
+      ContentSettingsType::MEDIASTREAM_CAMERA,
+      permissions::OneTimePermissionEvent::GRANTED_ONE_TIME, 2);
+
+  OtpEventExpectBucketCount(
+      ContentSettingsType::MEDIASTREAM_MIC,
+      permissions::OneTimePermissionEvent::EXPIRED_IN_BACKGROUND, 1);
+  OtpEventExpectBucketCount(
+      ContentSettingsType::MEDIASTREAM_CAMERA,
+      permissions::OneTimePermissionEvent::EXPIRED_IN_BACKGROUND, 1);
 }
 
 IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
@@ -438,6 +540,14 @@ IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
   // Request cam/mic permission, expect no prompt is triggered.
   GetUserMediaAndExpectGrantedPermission(
       permissions::PermissionRequestManager::ACCEPT_ONCE, false, 0);
+
+  // Ensure that only a single GRANTED_ONE_TIME event is recorded per permission
+  OtpEventExpectUniqueSample(
+      ContentSettingsType::MEDIASTREAM_MIC,
+      permissions::OneTimePermissionEvent::GRANTED_ONE_TIME, 1);
+  OtpEventExpectUniqueSample(
+      ContentSettingsType::MEDIASTREAM_CAMERA,
+      permissions::OneTimePermissionEvent::GRANTED_ONE_TIME, 1);
 }
 
 IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
@@ -452,12 +562,20 @@ IN_PROC_BROWSER_TEST_F(OneTimePermissionInteractiveUiTest,
   // web contents).
   CloseLastLocalStreamAt(0);
 
-  // Fire running timers. This means, that all one time permission expiration
-  // timers that are running at this point in time will fire their callbacks and
-  // are stopped.
+  // Fire running timers. This means, that all one time permission
+  // expiration timers that are running at this point in time will fire
+  // their callbacks and are stopped.
   FireRunningExpirationTimers();
 
   // Request cam/mic permission, expect no prompt is triggered.
   GetUserMediaAndExpectGrantedPermission(
       permissions::PermissionRequestManager::ACCEPT_ONCE, false, 0);
+
+  // Ensure that only a single GRANTED_ONE_TIME event is recorded per permission
+  OtpEventExpectUniqueSample(
+      ContentSettingsType::MEDIASTREAM_MIC,
+      permissions::OneTimePermissionEvent::GRANTED_ONE_TIME, 1);
+  OtpEventExpectUniqueSample(
+      ContentSettingsType::MEDIASTREAM_CAMERA,
+      permissions::OneTimePermissionEvent::GRANTED_ONE_TIME, 1);
 }
diff --git a/components/permissions/permission_uma_util.cc b/components/permissions/permission_uma_util.cc
index ef002e52ef9a4d..0c79f82bb8017d 100644
--- a/components/permissions/permission_uma_util.cc
+++ b/components/permissions/permission_uma_util.cc
@@ -1275,6 +1275,19 @@ void PermissionUmaUtil::RecordPageInfoDialogAccessType(
       "Permissions.ConfirmationChip.PageInfoDialogAccessType", access_type);
 }
 
+// static
+void PermissionUmaUtil::RecordOneTimePermissionEvent(
+    ContentSettingsType type,
+    OneTimePermissionEvent event) {
+  DCHECK(permissions::PermissionUtil::CanPermissionBeAllowedOnce(type));
+
+  std::string permission_type = GetPermissionRequestString(
+      GetUmaValueForRequestType(ContentSettingsTypeToRequestType(type)));
+
+  base::UmaHistogramEnumeration(
+      "Permissions.OneTimePermission." + permission_type + ".Event", event);
+}
+
 // static
 void PermissionUmaUtil::RecordPageInfoPermissionChangeWithin1m(
     ContentSettingsType type,
diff --git a/components/permissions/permission_uma_util.h b/components/permissions/permission_uma_util.h
index 601684f354ff94..a415313558798d 100644
--- a/components/permissions/permission_uma_util.h
+++ b/components/permissions/permission_uma_util.h
@@ -252,6 +252,28 @@ enum class AdaptiveTriggers {
   THREE_CONSECUTIVE_DENIES = 0x01,
 };
 
+// These values are logged to UMA. Entries should not be renumbered and
+// numeric values should never be reused. Please keep in sync with
+// "OneTimePermissionEvent" in tools/metrics/histograms/enums.xml.
+enum class OneTimePermissionEvent {
+  // Recorded for each one time grant
+  GRANTED_ONE_TIME = 0,
+
+  // Recorded when the user manually revokes a one time grant
+  REVOKED_MANUALLY = 1,
+
+  // Recorded when a one time grant expires because all tabs are either closed
+  // or discarded.
+
+  ALL_TABS_CLOSED_OR_DISCARDED = 2,
+
+  // Recorded when a one time grant expires because the permission was unused in
+  // the background.
+  EXPIRED_IN_BACKGROUND = 3,
+
+  kMaxValue = EXPIRED_IN_BACKGROUND
+};
+
 enum class PermissionAutoRevocationHistory {
   // Permission has not been automatically revoked.
   NONE = 0,
@@ -535,6 +557,9 @@ class PermissionUmaUtil {
   static void RecordPageInfoDialogAccessType(
       PageInfoDialogAccessType access_type);
 
+  static void RecordOneTimePermissionEvent(ContentSettingsType type,
+                                           OneTimePermissionEvent event);
+
   static void RecordPageInfoPermissionChangeWithin1m(
       ContentSettingsType type,
       PermissionAction previous_action,
diff --git a/tools/metrics/histograms/enums.xml b/tools/metrics/histograms/enums.xml
index d346428247f819..93710984f45566 100644
--- a/tools/metrics/histograms/enums.xml
+++ b/tools/metrics/histograms/enums.xml
@@ -76406,6 +76406,14 @@ Called by update_net_trust_anchors.py.-->
   <int value="6" label="Enforced by flag for dev"/>
 </enum>
 
+<enum name="OneTimePermissionEvent">
+  <summary>One-time permission events.</summary>
+  <int value="0" label="Granted one time"/>
+  <int value="1" label="Revoked one time grant manually"/>
+  <int value="2" label="Expired due to tab closure or discards"/>
+  <int value="3" label="Expired in the background due to non-usage"/>
+</enum>
+
 <enum name="OnServiceConnectedTimedOutResult">
   <int value="0" label="AlreadyConnected">
     OnServiceConnected is already called. Everything worked as expected.
diff --git a/tools/metrics/histograms/metadata/permissions/histograms.xml b/tools/metrics/histograms/metadata/permissions/histograms.xml
index 962170e1f6b552..41d2fdbeee7cb8 100644
--- a/tools/metrics/histograms/metadata/permissions/histograms.xml
+++ b/tools/metrics/histograms/metadata/permissions/histograms.xml
@@ -674,6 +674,26 @@ chromium-metrics-reviews@google.com.
   <token key="PermissionType" variants="Top2PermissionTypes"/>
 </histogram>
 
+<histogram name="Permissions.OneTimePermission.{PermissionType}.Event"
+    enum="OneTimePermissionEvent" expires_after="2024-04-20">
+  <owner>fjacky@chromium.org</owner>
+  <owner>src/components/permissions/PERMISSIONS_OWNERS</owner>
+  <summary>
+    Logs granting, revocation, and expiry behaviors of one time permissions. It
+    records grant events, manual revoke events, expiry due to tab closure or
+    discards, and expiry in the background due to non-usage. Note that the
+    number of grants that expired due to the 24 hour maximum grant time limit
+    can be aproximated by calculating #(granted one time) - #(other events),
+    though this does not take into account one time permissions that are still
+    currently active.
+  </summary>
+  <token key="PermissionType">
+    <variant name="AudioCapture"/>
+    <variant name="Geolocation"/>
+    <variant name="VideoCapture"/>
+  </token>
+</histogram>
+
 <histogram
     name="Permissions.PageInfo.Changed.{PermissionType}.Reallowed.Outcome"
     enum="PermissionChangeInfo" expires_after="2023-10-31">