diff --git a/Userland/Applications/Mail/InboxModel.cpp b/Userland/Applications/Mail/InboxModel.cpp
index 657d472a2a..055c817077 100644
--- a/Userland/Applications/Mail/InboxModel.cpp
+++ b/Userland/Applications/Mail/InboxModel.cpp
@@ -13,6 +13,12 @@ InboxModel::InboxModel(Vector<InboxEntry> entries)
 {
 }
 
+void InboxModel::set_seen(int row, bool seen)
+{
+    m_entries[row].seen = seen;
+    did_update(DontInvalidateIndices);
+}
+
 int InboxModel::row_count(GUI::ModelIndex const&) const
 {
     return m_entries.size();
diff --git a/Userland/Applications/Mail/InboxModel.h b/Userland/Applications/Mail/InboxModel.h
index b8c0c0e2e3..3a97c5aa8c 100644
--- a/Userland/Applications/Mail/InboxModel.h
+++ b/Userland/Applications/Mail/InboxModel.h
@@ -33,6 +33,8 @@ public:
 
     virtual ~InboxModel() override = default;
 
+    void set_seen(int row, bool);
+
     virtual int row_count(const GUI::ModelIndex& = GUI::ModelIndex()) const override;
     virtual int column_count(const GUI::ModelIndex& = GUI::ModelIndex()) const override { return Column::__Count; }
     virtual ErrorOr<String> column_name(int) const override;
diff --git a/Userland/Applications/Mail/MailWidget.cpp b/Userland/Applications/Mail/MailWidget.cpp
index 7024b8bc63..4370f7f9e5 100644
--- a/Userland/Applications/Mail/MailWidget.cpp
+++ b/Userland/Applications/Mail/MailWidget.cpp
@@ -243,7 +243,8 @@ bool MailWidget::is_supported_alternative(Alternative const& alternative) const
 
 void MailWidget::selected_mailbox()
 {
-    m_individual_mailbox_view->set_model(InboxModel::create({}));
+    m_individual_mailbox_model = InboxModel::create({});
+    m_individual_mailbox_view->set_model(m_individual_mailbox_model);
 
     auto const& index = m_mailbox_list->selection().first();
 
@@ -427,7 +428,8 @@ void MailWidget::selected_mailbox()
     }
 
     m_statusbar->set_text(String::formatted("[{}]: Loaded {} entries", mailbox.name, i).release_value_but_fixme_should_propagate_errors());
-    m_individual_mailbox_view->set_model(InboxModel::create(move(active_inbox_entries)));
+    m_individual_mailbox_model = InboxModel::create(move(active_inbox_entries));
+    m_individual_mailbox_view->set_model(m_individual_mailbox_model);
 }
 
 void MailWidget::selected_email_to_load()
@@ -509,6 +511,9 @@ void MailWidget::selected_email_to_load()
                 },
                 .partial_fetch = false,
             },
+            IMAP::FetchCommand::DataItem {
+                .type = IMAP::FetchCommand::DataItemType::Flags,
+            },
         },
     };
 
@@ -532,6 +537,9 @@ void MailWidget::selected_email_to_load()
 
     auto& fetch_response_data = fetch_data.last().get<IMAP::FetchResponseData>();
 
+    auto seen = !fetch_response_data.flags().find_if([](StringView value) { return value.equals_ignoring_ascii_case("\\Seen"sv); }).is_end();
+    m_individual_mailbox_model->set_seen(index.row(), seen);
+
     if (!fetch_response_data.contains_response_type(IMAP::FetchResponseType::Body)) {
         GUI::MessageBox::show_error(window(), "The server sent no body."sv);
         return;
diff --git a/Userland/Applications/Mail/MailWidget.h b/Userland/Applications/Mail/MailWidget.h
index dc73cb7525..be8a6b2c12 100644
--- a/Userland/Applications/Mail/MailWidget.h
+++ b/Userland/Applications/Mail/MailWidget.h
@@ -41,6 +41,7 @@ private:
     OwnPtr<IMAP::Client> m_imap_client;
 
     RefPtr<GUI::TreeView> m_mailbox_list;
+    RefPtr<InboxModel> m_individual_mailbox_model;
     RefPtr<GUI::TableView> m_individual_mailbox_view;
     RefPtr<WebView::OutOfProcessWebView> m_web_view;
     RefPtr<GUI::Statusbar> m_statusbar;