Yes, checkadvantage.com does offer site-wide discount codes. One can use the code REORDER15 to get 15% off sitewide. Another code, 25OFFBIZ, can be used to save 25% off business products. Please note that these codes may be subject to terms and conditions set by the website. It's always a good idea to check the website or contact their customer service for the most accurate and up-to-date information. Remember to apply the discount code at checkout to enjoy the savings. Happy shopping!