Yes, mhotonline.com does offer a site-wide discount code. There is a 35% off site-wide discount code available. Additionally, there are other discount codes such as 15% off, 20% off, 12% off, and 10% off available on the site. There is also a $10 off site-wide discount code. Please note that these codes are subject to change and it's recommended to check the website for the most current offers.