diff --git a/src/main/java/com/googlesource/gerrit/plugins/gitrepometrics/collectors/FSMetricsCollector.java b/src/main/java/com/googlesource/gerrit/plugins/gitrepometrics/collectors/FSMetricsCollector.java
index 15fd4c9..7d84061 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/gitrepometrics/collectors/FSMetricsCollector.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/gitrepometrics/collectors/FSMetricsCollector.java
@@ -81,10 +81,17 @@
       new GitRepoMetric("numberOfDirectories", "Number of directories on filesystem", "Count");
   protected static final GitRepoMetric numberOfFiles =
       new GitRepoMetric("numberOfFiles", "Number of directories on filesystem", "Count");
+  private static final GitRepoMetric collectionTime =
+      new GitRepoMetric(
+          "fsMetricsCollectionTime", "Timestamp at which metrics were collected", "Milliseconds");
 
   private static final ImmutableList<GitRepoMetric> availableMetrics =
       ImmutableList.of(
-          numberOfKeepFiles, numberOfEmptyDirectories, numberOfFiles, numberOfDirectories);
+          numberOfKeepFiles,
+          numberOfEmptyDirectories,
+          numberOfFiles,
+          numberOfDirectories,
+          collectionTime);
 
   private final ExecutorService executorService;
 
@@ -101,7 +108,10 @@
 
     executorService.submit(
         () -> {
-          populateMetrics.accept(filesAndDirectoriesCount(repository, projectName));
+          long collectionStartTime = System.currentTimeMillis();
+          HashMap<GitRepoMetric, Long> metrics = filesAndDirectoriesCount(repository, projectName);
+          metrics.put(collectionTime, collectionStartTime);
+          populateMetrics.accept(metrics);
         });
   }
 
diff --git a/src/main/java/com/googlesource/gerrit/plugins/gitrepometrics/collectors/GitRefsMetricsCollector.java b/src/main/java/com/googlesource/gerrit/plugins/gitrepometrics/collectors/GitRefsMetricsCollector.java
index 525195b..ab3e529 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/gitrepometrics/collectors/GitRefsMetricsCollector.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/gitrepometrics/collectors/GitRefsMetricsCollector.java
@@ -39,8 +39,12 @@
   protected static final GitRepoMetric combinedRefsSha1 =
       new GitRepoMetric("combinedRefsSha1", "Numeric value of combined refs SHA-1's", "Number");
 
+  private static final GitRepoMetric collectionTime =
+      new GitRepoMetric(
+          "refsMetricsCollectionTime", "Timestamp at which metrics were collected", "Milliseconds");
+
   private static final ImmutableList<GitRepoMetric> availableMetrics =
-      ImmutableList.of(combinedRefsSha1);
+      ImmutableList.of(combinedRefsSha1, collectionTime);
 
   private final ExecutorService executorService;
 
@@ -57,6 +61,7 @@
     executorService.submit(
         () -> {
           try {
+            long collectionStartTime = System.currentTimeMillis();
             MessageDigest md = MessageDigest.getInstance("SHA-1");
             repository.getRefDatabase().getRefs().stream()
                 .filter(ref -> !ref.isSymbolic())
@@ -66,6 +71,7 @@
 
             HashMap<GitRepoMetric, Long> metrics = new HashMap<>();
             metrics.put(combinedRefsSha1, (long) sha1Int);
+            metrics.put(collectionTime, collectionStartTime);
             populateMetrics.accept(metrics);
           } catch (NoSuchAlgorithmException e) {
             logger.atSevere().withCause(e).log(
diff --git a/src/main/java/com/googlesource/gerrit/plugins/gitrepometrics/collectors/GitStatsMetricsCollector.java b/src/main/java/com/googlesource/gerrit/plugins/gitrepometrics/collectors/GitStatsMetricsCollector.java
index 5c988ce..06b2c48 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/gitrepometrics/collectors/GitStatsMetricsCollector.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/gitrepometrics/collectors/GitStatsMetricsCollector.java
@@ -56,6 +56,9 @@
           "numberOfPackFilesSinceBitmap",
           "The number of pack files that were created after the last bitmap generation",
           "Count");
+  private static final GitRepoMetric collectionTime =
+      new GitRepoMetric(
+          "gitMetricsCollectionTime", "Timestamp at which metrics were collected", "Milliseconds");
 
   private static final ImmutableList<GitRepoMetric> availableMetrics =
       ImmutableList.of(
@@ -68,7 +71,8 @@
           sizeOfPackedObjects,
           numberOfBitmaps,
           numberOfObjectsSinceBitmap,
-          numberOfPackFilesSinceBitmap);
+          numberOfPackFilesSinceBitmap,
+          collectionTime);
 
   private final ExecutorService executorService;
 
@@ -88,6 +92,7 @@
         () -> {
           HashMap<GitRepoMetric, Long> metrics = new HashMap<>();
           try {
+            long collectionStartTime = System.currentTimeMillis();
             GC.RepoStatistics statistics = new GC(repository).getStatistics();
             metrics.put(numberOfPackedObjects, statistics.numberOfPackedObjects);
             metrics.put(numberOfPackFiles, statistics.numberOfPackFiles);
@@ -99,6 +104,7 @@
             metrics.put(numberOfBitmaps, statistics.numberOfBitmaps);
             metrics.put(numberOfObjectsSinceBitmap, statistics.numberOfObjectsSinceBitmap);
             metrics.put(numberOfPackFilesSinceBitmap, statistics.numberOfPackFilesSinceBitmap);
+            metrics.put(collectionTime, collectionStartTime);
             logger.atFine().log("New Git Statistics metrics collected: %s", statistics.toString());
           } catch (IOException e) {
             logger.atSevere().log("Something went wrong: %s", e.getMessage());
diff --git a/src/main/resources/Documentation/config.md b/src/main/resources/Documentation/config.md
index 10128f4..a7c9898 100644
--- a/src/main/resources/Documentation/config.md
+++ b/src/main/resources/Documentation/config.md
@@ -16,13 +16,16 @@
 plugins_git_repo_metrics_numberofpackfiles_<repo_name>
 plugins_git_repo_metrics_sizeoflooseobjects_<repo_name>
 plugins_git_repo_metrics_sizeofpackedobjects_<repo_name>
+plugins_git_repo_metrics_numberofobjectssincebitmap_<repo_name>
+plugins_git_repo_metrics_numberofpackfilessincebitmap_<repo_name>
+plugins_git_repo_metrics_gitmetricscollectiontime_<repo_name>
 plugins_git_repo_metrics_numberofkeepfiles_<repo_name>
 plugins_git_repo_metrics_numberoffiles_<repo_name>
 plugins_git_repo_metrics_numberofdirectories_<repo_name>
 plugins_git_repo_metrics_numberofemptydirectories_<repo_name>
+plugins_git_repo_metrics_fsmetricscollectiontime_<repo_name>
 plugins_git_repo_metrics_combinedrefssha1_<repo_name>
-plugins_git_repo_metrics_numberofobjectssincebitmap_<repo_name>
-plugins_git_repo_metrics_numberofpackfilessincebitmap_<repo_name>
+plugins_git_repo_metrics_refsmetricscollectiontime_<repo_name>
 ```
 
 > **NOTE**: The `<repo_name>` is a subject of sanitization in order to avoid collision between repository names.
@@ -31,6 +34,8 @@
 >   string for instance `repo/name` is sanitized to `repo_0x2F_name`
 > - if the repository name contains the replacement prefix `(_0x)` it is prefixed with another `_0x`
 >   e.g. `repo_0x2F_name` becomes `repo_0x_0x2F_name`.
+> - the `[git|fs|refs]metricscollectiontime` is a meta metric and represents system time (in millis) when the
+>   particular group of metrics was collected - to easily verify if the corresponding metrics are stale
 
 Settings
 --------