Anyone getting their HazMat endorsement are usually good for 5 years in most states although it can vary in different states! In Tennessee if you allow your HazMat endorsement to expire BEWARE! Your CDL will be canceled until you either get it taken off of your license or renew it! Trust me today is May 6th 2022 and this morning I woke up to find out that my license was canceled I had to go down and spend 5 hours at Tennessee DMV to get that HazMat endorsement taken off of my license and my license reinstated! Unbelievable