What reporting or documentation should I keep after winter pest treatment?

This isn't a courtesy a good company offers — it's a state requirement every commercial applicator already has to meet. NH administrative rule Pes 901.02 requires a daily record for each application covering the site and address, the date and time, the target pest, the product's brand name and its EPA registration number, the amount applied, and the applicator's name. That record has to be kept for at least two years.

Because the requirement exists independent of whether you ask, the honest move is simple: ask for your copy at the end of every visit, or request it retroactively for a treatment done earlier this season. A company with nothing to hide will produce it without friction.

Three concrete things. First, it's the receipt that lets you enforce a warranty — if a company promises re-service within a window and you need to invoke that, the dated record is your proof of when the clock started. Second, it's insurance evidence: if rodent activity leads to a secondary covered loss, like an electrical fire traced to gnawed wiring, an adjuster will want to see what was found and treated and when. Third, it's a resale asset — buyers and home inspectors increasingly ask about pest history, and a paper trail beats a verbal assurance.

Ask for the site and address, the date and time of the visit, the exact product name and its EPA registration number, the amount used, the target pest, and — separately, but ideally in the same document — any inspection findings such as entry points located or evidence observed. If a company gives you a vague summary ('treated for rodents') instead of these specifics, ask them to put the details in writing before the next visit.