diff --git a/src/Particular.LicensingComponent.UnitTests/ThroughputCollector/ThroughputCollector_ThroughputSummary_Tests.cs b/src/Particular.LicensingComponent.UnitTests/ThroughputCollector/ThroughputCollector_ThroughputSummary_Tests.cs
index ddb3725bec..a8fae5c875 100644
--- a/src/Particular.LicensingComponent.UnitTests/ThroughputCollector/ThroughputCollector_ThroughputSummary_Tests.cs
+++ b/src/Particular.LicensingComponent.UnitTests/ThroughputCollector/ThroughputCollector_ThroughputSummary_Tests.cs
@@ -176,6 +176,22 @@ await DataStore.CreateBuilder()
         }
     }
 
+    [Test]
+    [SetCulture("th-TH")]
+    public async Task Should_key_monthly_throughput_by_gregorian_month_when_the_culture_uses_another_calendar()
+    {
+        await DataStore.CreateBuilder()
+            .AddEndpoint("Endpoint1", sources: [ThroughputSource.Broker])
+            .WithThroughput(new ThroughputData([
+                new EndpointDailyThroughput(new DateOnly(2025, 1, 10), 50),
+                new EndpointDailyThroughput(new DateOnly(2025, 2, 20), 60)]))
+            .Build();
+
+        var summary = await ThroughputCollector.GetThroughputSummary(CancellationToken.None);
+
+        Assert.That(summary.Single().MonthlyThroughput, Is.EquivalentTo(new[] { new MonthlyThroughput("2025-01", 50), new MonthlyThroughput("2025-02", 60) }), "Monthly throughput must be keyed by Gregorian yyyy-MM months");
+    }
+
     [Test]
     public async Task Should_return_correct_max_daily_throughput_in_summary_when_endpoint_has_zero_throughput()
     {
diff --git a/src/Particular.LicensingComponent/ThroughputDataExtensions.cs b/src/Particular.LicensingComponent/ThroughputDataExtensions.cs
index 18a11ed2f6..db47a84a0d 100644
--- a/src/Particular.LicensingComponent/ThroughputDataExtensions.cs
+++ b/src/Particular.LicensingComponent/ThroughputDataExtensions.cs
@@ -1,5 +1,6 @@
 namespace Particular.LicensingComponent;
 
+using System.Globalization;
 using Contracts;
 
 static class ThroughputDataExtensions
@@ -29,7 +30,7 @@ public static MonthlyThroughput[] MonthlyThroughput(this List<ThroughputData> th
             .Where(x => x.Value >= 0)
             .GroupBy(x => x.Key, x => x.Value)
             .ToLookup(x => x.Key, x => x.Max())
-            .GroupBy(kvp => $"{kvp.Key:yyyy-MM}", x => x.Sum())
+            .GroupBy(kvp => kvp.Key.ToString("yyyy-MM", CultureInfo.InvariantCulture), x => x.Sum())
             .Select(group => new MonthlyThroughput(group.Key, group.Sum()))];
 
     public static long AverageMonthlyThroughput(this List<ThroughputData> throughputs)
diff --git a/src/Particular.LicensingComponent/WebApi/LicensingController.cs b/src/Particular.LicensingComponent/WebApi/LicensingController.cs
index 99019ae60c..ad011a2aa5 100644
--- a/src/Particular.LicensingComponent/WebApi/LicensingController.cs
+++ b/src/Particular.LicensingComponent/WebApi/LicensingController.cs
@@ -1,5 +1,6 @@
 namespace Particular.LicensingComponent.WebApi
 {
+    using System.Globalization;
     using System.IO.Compression;
     using System.Text;
     using System.Text.Json;
@@ -66,7 +67,7 @@ public async Task GetThroughputReportFile([FromQuery(Name = "spVersion")] string
                 null,
                 cancellationToken);
 
-            var fileName = $"{report.ReportData.CustomerName}.throughput-report-{report.ReportData.EndTime:yyyyMMdd-HHmmss}";
+            var fileName = $"{report.ReportData.CustomerName}.throughput-report-{report.ReportData.EndTime.ToString("yyyyMMdd-HHmmss", CultureInfo.InvariantCulture)}";
 
             HttpContext.Response.ContentType = "application/zip";
             HttpContext.Response.Headers[HeaderNames.ContentDisposition] = new ContentDispositionHeaderValue("attachment")