diff --git a/mailer/mailer_test.go b/mailer/mailer_test.go
new file mode 100644
index 0000000..6ca530b
--- /dev/null
+++ b/mailer/mailer_test.go
@@ -0,0 +1,52 @@
+/*
+ * Copyright © 2026 Musing Studio LLC.
+ *
+ * This file is part of WriteFreely.
+ *
+ * WriteFreely is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, included
+ * in the LICENSE file in this source code package.
+ */
+
+package mailer
+
+import (
+	netmail "net/mail"
+	"testing"
+
+	mail "github.com/xhit/go-simple-mail/v2"
+)
+
+func TestFormatAddress(t *testing.T) {
+	cases := []struct {
+		name, address string
+	}{
+		{"Le blog", "le-blog@example.com"},
+		{"A, B, C et D", "sender@example.net"},
+		{"", "noreply@example.com"},
+	}
+	for _, c := range cases {
+		got := FormatAddress(c.name, c.address)
+		addr, err := netmail.ParseAddress(got)
+		if err != nil {
+			t.Fatalf("FormatAddress(%q, %q) = %q, which failed to parse: %v", c.name, c.address, got, err)
+		}
+		if addr.Address != c.address {
+			t.Errorf("FormatAddress(%q, %q) = %q, parsed address = %q, want %q", c.name, c.address, got, addr.Address, c.address)
+		}
+	}
+}
+
+func TestNewMessageDoesNotAddPhantomRecipients(t *testing.T) {
+	m := &Mailer{smtp: mail.NewSMTPClient()}
+	msg, err := m.NewMessage("Test <from@example.com>", "Subject", "body", "<to@example.com>")
+	if err != nil {
+		t.Fatalf("NewMessage returned error: %v", err)
+	}
+	if len(msg.smtpMsg.recipients) != 1 {
+		t.Fatalf("expected 1 recipient, got %d: %+v", len(msg.smtpMsg.recipients), msg.smtpMsg.recipients)
+	}
+	if msg.smtpMsg.recipients[0].email != "<to@example.com>" {
+		t.Errorf("unexpected recipient: %+v", msg.smtpMsg.recipients[0])
+	}
+}