diff --git a/src/ZB.MOM.WW.ScadaBridge.Commons/Messages/Notification/NotificationOutboxQueries.cs b/src/ZB.MOM.WW.ScadaBridge.Commons/Messages/Notification/NotificationOutboxQueries.cs
index 45803fa3..7c25b2f0 100644
--- a/src/ZB.MOM.WW.ScadaBridge.Commons/Messages/Notification/NotificationOutboxQueries.cs
+++ b/src/ZB.MOM.WW.ScadaBridge.Commons/Messages/Notification/NotificationOutboxQueries.cs
@@ -6,6 +6,11 @@ namespace ZB.MOM.WW.ScadaBridge.Commons.Messages.Notification;
 /// Outbox UI -> Central: paginated, filtered query over the notification outbox.
 /// All filter fields are optional; <see cref="StuckOnly"/> restricts results to stuck notifications.
 /// </summary>
+/// <param name="NotificationIdFilter">
+/// Exact match on a single notification — the <c>?correlationId=</c> deep link from the
+/// Flow Debugger / Audit Log. Additive; <c>null</c> means "no filter" (legacy senders
+/// compile unchanged).
+/// </param>
 public record NotificationOutboxQueryRequest(
     string CorrelationId,
     string? StatusFilter,
@@ -18,7 +23,8 @@ public record NotificationOutboxQueryRequest(
     DateTimeOffset? To,
     int PageNumber,
     int PageSize,
-    string? SourceNodeFilter = null);
+    string? SourceNodeFilter = null,
+    string? NotificationIdFilter = null);
 
 /// <summary>
 /// A single notification row summarised for outbox UI display.
diff --git a/src/ZB.MOM.WW.ScadaBridge.Commons/Types/Notifications/NotificationOutboxFilter.cs b/src/ZB.MOM.WW.ScadaBridge.Commons/Types/Notifications/NotificationOutboxFilter.cs
index 2d27ab42..307bd732 100644
--- a/src/ZB.MOM.WW.ScadaBridge.Commons/Types/Notifications/NotificationOutboxFilter.cs
+++ b/src/ZB.MOM.WW.ScadaBridge.Commons/Types/Notifications/NotificationOutboxFilter.cs
@@ -23,6 +23,10 @@ namespace ZB.MOM.WW.ScadaBridge.Commons.Types.Notifications;
 /// <c>"central-a"</c>, <c>"site-plant-a-node-a"</c>). Exact match; <c>null</c>
 /// means "do not constrain".
 /// </param>
+/// <param name="NotificationId">
+/// Exact match on a single <c>NotificationId</c> — the <c>?correlationId=</c> deep link
+/// from the Flow Debugger / Audit Log. <c>null</c> means "do not constrain".
+/// </param>
 public record NotificationOutboxFilter(
     NotificationStatus? Status = null,
     NotificationType? Type = null,
@@ -33,4 +37,5 @@ public record NotificationOutboxFilter(
     DateTimeOffset? StuckCutoff = null,
     DateTimeOffset? From = null,
     DateTimeOffset? To = null,
-    string? SourceNode = null);
+    string? SourceNode = null,
+    string? NotificationId = null);
diff --git a/src/ZB.MOM.WW.ScadaBridge.ConfigurationDatabase/Repositories/NotificationOutboxRepository.cs b/src/ZB.MOM.WW.ScadaBridge.ConfigurationDatabase/Repositories/NotificationOutboxRepository.cs
index f005c08e..b3f5af4a 100644
--- a/src/ZB.MOM.WW.ScadaBridge.ConfigurationDatabase/Repositories/NotificationOutboxRepository.cs
+++ b/src/ZB.MOM.WW.ScadaBridge.ConfigurationDatabase/Repositories/NotificationOutboxRepository.cs
@@ -280,6 +280,12 @@ VALUES
             query = query.Where(n => n.Type == type);
         }
 
+        // Exact match on one notification — the ?correlationId= deep link.
+        if (!string.IsNullOrEmpty(filter.NotificationId))
+        {
+            query = query.Where(n => n.NotificationId == filter.NotificationId);
+        }
+
         if (!string.IsNullOrEmpty(filter.SourceSiteId))
         {
             query = query.Where(n => n.SourceSiteId == filter.SourceSiteId);
diff --git a/src/ZB.MOM.WW.ScadaBridge.NotificationOutbox/NotificationOutboxActor.cs b/src/ZB.MOM.WW.ScadaBridge.NotificationOutbox/NotificationOutboxActor.cs
index f478aef3..412053b5 100644
--- a/src/ZB.MOM.WW.ScadaBridge.NotificationOutbox/NotificationOutboxActor.cs
+++ b/src/ZB.MOM.WW.ScadaBridge.NotificationOutbox/NotificationOutboxActor.cs
@@ -940,7 +940,8 @@ public class NotificationOutboxActor : ReceiveActor, IWithTimers
             StuckCutoff: request.StuckOnly ? StuckCutoff(now) : null,
             From: request.From,
             To: request.To,
-            SourceNode: request.SourceNodeFilter);
+            SourceNode: request.SourceNodeFilter,
+            NotificationId: request.NotificationIdFilter);
 
         using var scope = _serviceProvider.CreateScope();
         var repository = scope.ServiceProvider.GetRequiredService<INotificationOutboxRepository>();
diff --git a/tests/ZB.MOM.WW.ScadaBridge.ConfigurationDatabase.Tests/Repositories/NotificationOutboxRepositoryIntegrationTests.cs b/tests/ZB.MOM.WW.ScadaBridge.ConfigurationDatabase.Tests/Repositories/NotificationOutboxRepositoryIntegrationTests.cs
index 93a483eb..8587b73c 100644
--- a/tests/ZB.MOM.WW.ScadaBridge.ConfigurationDatabase.Tests/Repositories/NotificationOutboxRepositoryIntegrationTests.cs
+++ b/tests/ZB.MOM.WW.ScadaBridge.ConfigurationDatabase.Tests/Repositories/NotificationOutboxRepositoryIntegrationTests.cs
@@ -1,6 +1,7 @@
 using Microsoft.EntityFrameworkCore;
 using ZB.MOM.WW.ScadaBridge.Commons.Entities.Notifications;
 using ZB.MOM.WW.ScadaBridge.Commons.Types.Enums;
+using ZB.MOM.WW.ScadaBridge.Commons.Types.Notifications;
 using ZB.MOM.WW.ScadaBridge.ConfigurationDatabase;
 using ZB.MOM.WW.ScadaBridge.ConfigurationDatabase.Repositories;
 using ZB.MOM.WW.ScadaBridge.ConfigurationDatabase.Tests.Migrations;
@@ -101,6 +102,33 @@ public class NotificationOutboxRepositoryIntegrationTests : IClassFixture<MsSqlM
         Assert.Equal(1, count);
     }
 
+    [SkippableFact]
+    public async Task QueryAsync_NotificationIdFilter_ReturnsExactlyThatRow()
+    {
+        Skip.IfNot(_fixture.Available, _fixture.SkipReason);
+
+        // Flow Debugger / Audit Log ?correlationId= deep link: an exact match on one
+        // NotificationId must return that single row and count it alone.
+        var wantedId = Guid.NewGuid().ToString();
+        var otherId = Guid.NewGuid().ToString();
+        await using (var context = CreateContext())
+        {
+            var repo = new NotificationOutboxRepository(context);
+            await repo.InsertIfNotExistsAsync(MakeNotification(wantedId, subject: "Wanted"));
+            await repo.InsertIfNotExistsAsync(MakeNotification(otherId, subject: "Other"));
+        }
+
+        await using var queryContext = CreateContext();
+        var queryRepo = new NotificationOutboxRepository(queryContext);
+        var (rows, totalCount) = await queryRepo.QueryAsync(
+            new NotificationOutboxFilter(NotificationId: wantedId), pageNumber: 1, pageSize: 50);
+
+        Assert.Equal(1, totalCount);
+        var row = Assert.Single(rows);
+        Assert.Equal(wantedId, row.NotificationId);
+        Assert.Equal("Wanted", row.Subject);
+    }
+
     // --- helpers ------------------------------------------------------------
 
     private ScadaBridgeDbContext CreateContext()
diff --git a/tests/ZB.MOM.WW.ScadaBridge.NotificationOutbox.Tests/NotificationOutboxActorQueryTests.cs b/tests/ZB.MOM.WW.ScadaBridge.NotificationOutbox.Tests/NotificationOutboxActorQueryTests.cs
index fe3143dd..c87f5f96 100644
--- a/tests/ZB.MOM.WW.ScadaBridge.NotificationOutbox.Tests/NotificationOutboxActorQueryTests.cs
+++ b/tests/ZB.MOM.WW.ScadaBridge.NotificationOutbox.Tests/NotificationOutboxActorQueryTests.cs
@@ -115,6 +115,40 @@ public class NotificationOutboxActorQueryTests : TestKit
         Assert.Equal("site-1", staleSummary.SourceSiteId);
     }
 
+    [Fact]
+    public void Query_WithNotificationIdFilter_PassesExactMatchToRepositoryFilter()
+    {
+        _repository.QueryAsync(
+                Arg.Any<NotificationOutboxFilter>(), Arg.Any<int>(), Arg.Any<int>(), Arg.Any<CancellationToken>())
+            .Returns(((IReadOnlyList<Notification>)Array.Empty<Notification>(), 0));
+        var actor = CreateActor();
+
+        actor.Tell(
+            new NotificationOutboxQueryRequest(
+                CorrelationId: "corr-nid",
+                StatusFilter: null,
+                TypeFilter: null,
+                SourceSiteFilter: null,
+                ListNameFilter: null,
+                StuckOnly: false,
+                SubjectKeyword: null,
+                From: null,
+                To: null,
+                PageNumber: 1,
+                PageSize: 50,
+                NotificationIdFilter: "abc"),
+            TestActor);
+
+        var response = ExpectMsg<NotificationOutboxQueryResponse>();
+        Assert.True(response.Success);
+
+        // The ?correlationId= deep link from the Flow Debugger / Audit Log rides through
+        // to the repository as an exact-match NotificationId constraint.
+        _repository.Received(1).QueryAsync(
+            Arg.Is<NotificationOutboxFilter>(f => f.NotificationId == "abc"),
+            1, 50, Arg.Any<CancellationToken>());
+    }
+
     [Fact]
     public void Query_WithStatusFilterString_ParsesToEnumOnFilter()
     {