diff --git a/Orm/Xtensive.Orm.PostgreSql/Sql.Drivers.PostgreSql/Connection.cs b/Orm/Xtensive.Orm.PostgreSql/Sql.Drivers.PostgreSql/Connection.cs
index 6d8e8cccf1..82798b1af6 100644
--- a/Orm/Xtensive.Orm.PostgreSql/Sql.Drivers.PostgreSql/Connection.cs
+++ b/Orm/Xtensive.Orm.PostgreSql/Sql.Drivers.PostgreSql/Connection.cs
@@ -52,9 +52,7 @@ public override void Commit()
       EnsureTransactionIsActive();
 
       try {
-        if (!IsTransactionCompleted()) {
-          ActiveTransaction.Commit();
-        }
+        ActiveTransaction.Commit();
       }
       finally {
         ActiveTransaction.Dispose();
@@ -67,9 +65,7 @@ public override async Task CommitAsync(CancellationToken token = default)
       EnsureIsNotDisposed();
       EnsureTransactionIsActive();
       try {
-        if (!IsTransactionCompleted()) {
-          await ActiveTransaction.CommitAsync(token).ConfigureAwait(false);
-        }
+        await ActiveTransaction.CommitAsync(token).ConfigureAwait(false);
       }
       finally {
         await ActiveTransaction.DisposeAsync().ConfigureAwait(false);
@@ -83,9 +79,7 @@ public override void Rollback()
       EnsureTransactionIsActive();
 
       try {
-        if (!IsTransactionCompleted()) {
-          ActiveTransaction.Rollback();
-        }
+        ActiveTransaction.Rollback();
       }
       finally {
         ActiveTransaction.Dispose();
@@ -98,9 +92,7 @@ public override async Task RollbackAsync(CancellationToken token = default)
       EnsureIsNotDisposed();
       EnsureTransactionIsActive();
       try {
-        if (!IsTransactionCompleted()) {
-          await ActiveTransaction.RollbackAsync(token).ConfigureAwait(false);
-        }
+        await ActiveTransaction.RollbackAsync(token).ConfigureAwait(false);
       }
       finally {
         await ActiveTransaction.DisposeAsync().ConfigureAwait(false);
@@ -182,11 +174,7 @@ private async Task ExecuteNonQueryAsync(string commandText, CancellationToken to
         await command.ExecuteNonQueryAsync(token).ConfigureAwait(false);
       }
     }
-
-    private bool IsTransactionCompleted()
-    {
-      return activeTransaction != null && activeTransaction.IsCompleted;
-    }
+    
 
     // Constructors
 
diff --git a/Orm/Xtensive.Orm.PostgreSql/Sql.Drivers.PostgreSql/v10_0/TypeMapper.cs b/Orm/Xtensive.Orm.PostgreSql/Sql.Drivers.PostgreSql/v10_0/TypeMapper.cs
index 9e1908f62f..75b5f9fdd4 100644
--- a/Orm/Xtensive.Orm.PostgreSql/Sql.Drivers.PostgreSql/v10_0/TypeMapper.cs
+++ b/Orm/Xtensive.Orm.PostgreSql/Sql.Drivers.PostgreSql/v10_0/TypeMapper.cs
@@ -4,11 +4,38 @@
 // Created by: Alexey Kulakov
 // Created:    2019.09.25
 
+using System;
+using System.Data.Common;
+using System.Security;
+using Npgsql;
+using NpgsqlTypes;
+
 namespace Xtensive.Sql.Drivers.PostgreSql.v10_0
 {
   internal class TypeMapper : v9_1.TypeMapper
   {
     // Constructors
+    
+    [SecuritySafeCritical]
+    public override void BindDateTime(DbParameter parameter, object value)
+    {
+      var nativeParameter = (NpgsqlParameter) parameter;
+      nativeParameter.NpgsqlDbType = NpgsqlDbType.Timestamp;
+      
+      if (value is DateTime {Kind: DateTimeKind.Utc} dateTime) {
+        value = DateTime.SpecifyKind(dateTime, DateTimeKind.Unspecified);
+      }
+      nativeParameter.NpgsqlValue = value ?? DBNull.Value;
+    }
+
+    public override SqlValueType MapDateTime(int? length, int? precision, int? scale) => new (SqlType.DateTime);
+
+    public override object ReadDateTime(DbDataReader reader, int index) 
+    {
+      var nativeReader = (NpgsqlDataReader) reader;
+      var value = nativeReader.GetFieldValue<DateTime>(index);
+      return value;
+    }
 
     public TypeMapper(SqlDriver driver)
       : base(driver)
diff --git a/Orm/Xtensive.Orm.PostgreSql/Sql.Drivers.PostgreSql/v8_0/TypeMapper.cs b/Orm/Xtensive.Orm.PostgreSql/Sql.Drivers.PostgreSql/v8_0/TypeMapper.cs
index 4e419085d3..aad930805f 100644
--- a/Orm/Xtensive.Orm.PostgreSql/Sql.Drivers.PostgreSql/v8_0/TypeMapper.cs
+++ b/Orm/Xtensive.Orm.PostgreSql/Sql.Drivers.PostgreSql/v8_0/TypeMapper.cs
@@ -129,6 +129,10 @@ public override void BindDateTimeOffset(DbParameter parameter, object value)
     {
       var nativeParameter = (NpgsqlParameter) parameter;
       nativeParameter.NpgsqlDbType = NpgsqlDbType.TimestampTz;
+      if (value is DateTimeOffset dateTimeOffset) {
+        var localTimeTicks = dateTimeOffset.UtcTicks;
+        value = new DateTimeOffset(localTimeTicks, TimeSpan.Zero);
+      }
       nativeParameter.NpgsqlValue = value ?? DBNull.Value;
     }
 
@@ -195,7 +199,7 @@ public override object ReadDateTimeOffset(DbDataReader reader, int index)
     {
       var nativeReader = (NpgsqlDataReader) reader;
       var value = nativeReader.GetFieldValue<DateTimeOffset>(index);
-      return value;
+      return value.ToLocalTime();
     }
 
     // Constructors
diff --git a/Orm/Xtensive.Orm.PostgreSql/Xtensive.Orm.PostgreSql.csproj b/Orm/Xtensive.Orm.PostgreSql/Xtensive.Orm.PostgreSql.csproj
index 47da25e64c..871f3ce324 100644
--- a/Orm/Xtensive.Orm.PostgreSql/Xtensive.Orm.PostgreSql.csproj
+++ b/Orm/Xtensive.Orm.PostgreSql/Xtensive.Orm.PostgreSql.csproj
@@ -21,7 +21,7 @@
     <DefineConstants>TRACE</DefineConstants>
   </PropertyGroup>
   <ItemGroup>
-    <PackageReference Include="Npgsql" Version="4.1.3.1" />
+    <PackageReference Include="Npgsql" Version="6.0.3" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\Xtensive.Orm\Xtensive.Orm.csproj" />
diff --git a/Orm/Xtensive.Orm.Tests/Xtensive.Orm.Tests.csproj b/Orm/Xtensive.Orm.Tests/Xtensive.Orm.Tests.csproj
index dcbc9fe682..e93fc7aaec 100644
--- a/Orm/Xtensive.Orm.Tests/Xtensive.Orm.Tests.csproj
+++ b/Orm/Xtensive.Orm.Tests/Xtensive.Orm.Tests.csproj
@@ -14,7 +14,7 @@
   <ItemGroup>
     <!-- <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.3.0" /> -->
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.0.0" />
-    <PackageReference Include="Npgsql" Version="4.1.3.1" />
+    <PackageReference Include="Npgsql" Version="6.0.3" />
     <PackageReference Include="NUnit" Version="3.13.2" />
     <PackageReference Include="NUnit3TestAdapter" Version="4.2.0" />
     <PackageReference Include="System.CodeDom" Version="4.4.0" />
@@ -102,4 +102,4 @@
       <DependentUpon>TwoPartsModel.tt</DependentUpon>
     </Compile>
   </ItemGroup>
-</Project>
\ No newline at end of file
+</Project>