How long after best if used by date is mac and chees good?

Mac and cheese can still be safe to eat for a short period after the "best if used by" date, typically 1 to 3 months, if it has been stored properly. However, the quality may decline in terms of flavor and texture. Always check for signs of spoilage, such as off smells or visible mold, before consuming. If it's a packaged version, refer to the manufacturer's guidelines for the best advice.