diff --git a/Elwig/Documents/Document.cs b/Elwig/Documents/Document.cs
index 4b24506..77fa503 100644
--- a/Elwig/Documents/Document.cs
+++ b/Elwig/Documents/Document.cs
@@ -30,7 +30,7 @@ namespace Elwig.Documents {
         public string Author;
         public string Header;
         public string Footer;
-        public DateTime Date;
+        public DateOnly Date;
 
         public Document(string title) {
             var c = App.Client;
@@ -47,7 +47,7 @@ namespace Elwig.Documents {
                     .Item("Betriebs-Nr.", c.LfbisNr).Item("UID", c.UstIdNr).NextLine()
                 .Item("BIC", c.Bic).Item("IBAN", c.Iban)
                 .ToString();
-            Date = DateTime.Today;
+            Date = DateOnly.FromDateTime(Utils.Today);
         }
 
         ~Document() {
diff --git a/Elwig/Windows/MailWindow.xaml b/Elwig/Windows/MailWindow.xaml
index 27992e5..a00e448 100644
--- a/Elwig/Windows/MailWindow.xaml
+++ b/Elwig/Windows/MailWindow.xaml
@@ -94,9 +94,10 @@
 
                 <TextBox x:Name="PostalLocation" Grid.Column="1"
                          Margin="10,30,10,10" Width="120" HorizontalAlignment="Left"/>
-                <Label Margin="130,30,10,10" FontSize="14" Grid.Column="1">
-                    <TextBlock>, am <Run x:Name="PostalDate">01.01.2020</Run></TextBlock>
-                </Label>
+                <Label Content=", am" Margin="130,30,10,10" FontSize="14" Grid.Column="1"/>
+                <TextBox x:Name="PostalDate" Grid.Column="1" Text="01.01.2020"
+                         Margin="162,30,10,10" Width="78" HorizontalAlignment="Left"
+                         TextChanged="Date_TextChanged" LostFocus="Date_LostFocus"/>
 
                 <GroupBox Header="Adressaten" Margin="10,70,10,47" Grid.Column="1">
                     <Grid>
diff --git a/Elwig/Windows/MailWindow.xaml.cs b/Elwig/Windows/MailWindow.xaml.cs
index 0588be8..c04c4e8 100644
--- a/Elwig/Windows/MailWindow.xaml.cs
+++ b/Elwig/Windows/MailWindow.xaml.cs
@@ -303,6 +303,15 @@ namespace Elwig.Windows {
             await UpdateRecipients(ctx);
         }
 
+        private void Date_TextChanged(object sender, RoutedEventArgs evt) {
+            Validator.CheckDate((TextBox)sender, true);
+        }
+
+        private void Date_LostFocus(object sender, RoutedEventArgs evt) {
+            var res = Validator.CheckDate((TextBox)sender, true);
+            if (!res.IsValid) ((TextBox)sender).Text = $"{Utils.Today:dd.MM.yyyy}";
+        }
+
         private async Task UpdateRecipients(AppDbContext ctx) {
             if (RecipientsCustomInput.IsChecked == true) {
                 Recipients = MemberCustomInput.SelectedItems.Cast<Member>().ToList();
@@ -493,6 +502,7 @@ namespace Elwig.Windows {
                 }
             }
 
+            var postalDate = DateOnly.ParseExact(PostalDate.Text, "dd.MM.yyyy");
             var memberDocs = recipients.Select(m => new {
                 Member = m,
                 Docs = docs.SelectMany<SelectedDoc, GeneratedDoc>(doc => {
@@ -500,7 +510,7 @@ namespace Elwig.Windows {
                         if (doc.Type == DocType.Custom) {
                             return [new GeneratedDoc((string)doc.Details!)];
                         } else if (doc.Type == DocType.MemberDataSheet) {
-                            return [new GeneratedDoc(new MemberDataSheet(m, ctx))];
+                            return [new GeneratedDoc(new MemberDataSheet(m, ctx) { Date = postalDate })];
                         } else if (doc.Type == DocType.DeliveryConfirmation) {
                             var details = ((int, bool))doc.Details!;
                             var year = details.Item1;
@@ -513,7 +523,7 @@ namespace Elwig.Windows {
                             } else {
                                 return [];
                             }
-                            return [new GeneratedDoc(new DeliveryConfirmation(ctx, year, m, data))];
+                            return [new GeneratedDoc(new DeliveryConfirmation(ctx, year, m, data) { Date = postalDate })];
                         } else if (doc.Type == DocType.CreditNote) {
                             var details = ((int, int))doc.Details!;
                             var year = details.Item1;
@@ -521,12 +531,12 @@ namespace Elwig.Windows {
                             var data = cnData[(year, avnr)];
                             try {
                                 return [new GeneratedDoc(new CreditNote(
-                                ctx, data.Item2[m.MgNr], data.Item1[m.MgNr],
-                                data.Item3.ConsiderContractPenalties,
-                                data.Item3.ConsiderTotalPenalty,
-                                data.Item3.ConsiderAutoBusinessShares,
-                                ctx.GetMemberUnderDelivery(year, m.MgNr).GetAwaiter().GetResult()
-                            ))];
+                                    ctx, data.Item2[m.MgNr], data.Item1[m.MgNr],
+                                    data.Item3.ConsiderContractPenalties,
+                                    data.Item3.ConsiderTotalPenalty,
+                                    data.Item3.ConsiderAutoBusinessShares,
+                                    ctx.GetMemberUnderDelivery(year, m.MgNr).GetAwaiter().GetResult()
+                                ) { Date = postalDate })];
                             } catch (Exception) {
                                 return [];
                             }