Do I have to redo the NHD if escrow falls out and we go back on market?

Short answer: nothing in Civil Code §1103 stamps an expiration date on a Natural Hazard Disclosure report. If the first buyer walked and the property goes back on market a few weeks later, you are not automatically out of compliance handing the same report to the next buyer.

The longer answer is the one that keeps people out of trouble. A hazard report is a snapshot. It speaks as of the day it was pulled, using the maps and the tax data that existed that day. Fire hazard severity zones get re-adopted. Flood maps get revised. Special assessments and supplemental tax figures change with the roll. If any of that could have shifted between your first buyer and your second, the report you are handing over is describing a property as it was, not as it is — and you are the one delivering it.

So here is how I would decide. Order a fresh report when any of these is true: the zone maps or local ordinances in that area have been updated since the original pull, the tax year has turned over, the new buyer’s lender or escrow officer asks for a current report, or enough time has passed that you would not feel comfortable saying “this is current” out loud. If none of those apply and it has been a matter of weeks, reusing it is defensible.

What I would not do is guess quietly. Reordering costs a fraction of one hour of your time in a dispute, and the second report resets the clock on the buyer’s three-day or five-day review period cleanly, with a delivery date nobody has to reconstruct later.

One practical note: every Verity report carries a dated determination showing exactly which government layers were checked and when. That means you can put two reports side by side and see whether anything actually moved — and if a question ever comes up two years from now, the record answers it for you instead of you answering from memory.