Post Height for New Mailbox

Hi friends,

My mailbox kicked the bucket and I’m upgrading. I was going to do a ground mount install with a steel post, but Lowes and Home Depot seem to sell mailbox posts that are too short.

The USPS says it should be 24" underground and 41" - 45" high. Even considering the curb height, I feel like all the steel posts for sale are way too short - around 53". What am I missing?


12” embedment into soil seems plenty. I imagine the USPS guideline is for states where frost heaving is more of a consideration. You could always set the post in concrete if you want to be sure about stability.

Edit: looks like 24” is actually the maximum they recommend, so it’s not too sturdy to yield in a crash. Today I learned.

I just installed a new post myself a while back. I put mine in about 16 inches or so with concrete.