Municipal and institutional customers are the best accounts in portable sanitation: they rent for years, they never dispute a cleaning, and they pay. They also pay late more often than anyone else, and it is almost never because they are short of money. It is because the invoice was not a proper invoice, and a proper invoice is the only thing accounts payable is allowed to pay.
What accounts payable actually needs
Most public agencies work under a prompt payment rule that starts a clock when a proper invoice arrives. "Proper" has a definition, and it is roughly:
- The purchase order number, matching one they issued.
- The service period, in dates that match the PO's term.
- The site or location, so it can be coded to the right budget line.
- Itemized charges that add up to a number the PO allows.
- Your remit-to name and address, as registered with them as a vendor.
Miss any one and the invoice is returned, politely, three weeks later. The clock has not started. The fix is to build each of those into the invoice before it goes out, not into a follow-up email.
The PO number lives on the customer, not in your head
A blanket PO for the fiscal year is the normal case. Store it on the customer record, print it on every invoice, and when the new fiscal year's PO arrives, change it once. A site with its own PO, a school district with one PO per campus, gets the number on the site, and the site's number wins on that site's invoices.
One subtlety that costs real money: an invoice that has gone out should keep the PO it went out with. If you change the customer's PO in July and the system re-labels June's open invoice with the new number, the clerk who matched it to the old PO can no longer find it. Freeze the PO on the invoice when it is issued.
One invoice per site
A parks department with restrooms in twelve parks does not have one budget. It has twelve budget lines, and sometimes twelve POs. One invoice for all twelve parks has to be split by hand, coded twelve ways and approved by whoever owns each line. That invoice sits.
Turn on per-site invoicing for that customer and a cycle produces twelve invoices on the same day, each with its park, its PO and its own total. Send them as one email that opens a page where every invoice can be viewed, downloaded as a ZIP, printed, and paid together. The customer gets one email; the clerk gets twelve clean documents. The same setup works for a builder with a dozen lots.
Calendar months, and sometimes in advance
Municipal budgets are monthly, so their invoices should be too, even if the rest of your book bills every 28 days. Set those customers to calendar months individually; the billing cycle post explains the mechanics. Some agencies also need the invoice before the period starts to get PO approval, which is advance billing: next month's recurring charges go out ahead, and any extra services from last month are a labeled true-up on the same invoice.
Register as a vendor before the first invoice
Every agency has a vendor form, a W-9 request and often an insurance certificate requirement. Do them when you win the account, not when the first invoice bounces. Keep the registered remit-to name identical on your invoice template, down to the suite number. "PortaPro Sanitation LLC" and "Porta Pro Sanitation" are two different vendors to a procurement system.
Give them the portal
An AP clerk who can log in, see every invoice for every site, download the one she is looking for and pay it by ACH without calling you is a clerk who pays on time. A customer portal is the single most effective tool for institutional accounts; here is what it should do.
