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Due on delivery. Now they want 60 days. That is a new deal, so price it like one.

The work was delivered, the invoice said due on delivery, and now the client asks for 60 days, usually framed as how their payments simply work. Maybe their process really is slow. Maybe the ask is the first move in a stall. Either way, agreeing silently rewrites the deal you both already made, after you have given up the only leverage you had, which was the work itself. You do not have to refuse, and you do not have to swallow it. Anchor the clock to the day the client accepted the work, pick one of three clean doors, and get whatever you agree written down with an exact date on it. Here is the method, step by step.

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Updated October 29, 2026. First published October 29, 2026. The two delivery records quoted below are real and public, with their client decision states read back from the live service.

Step 1. Name what is actually being asked

Due on delivery was a term, agreed before the work started, and it is part of the price you quoted: a price for payment on delivery is a different price from the same figure paid two months later, because for 60 days you are lending the client the amount of the invoice, unpaid, unsecured, and usually interest free. Naming that, first to yourself and then calmly to the client, changes the conversation from a favour you are refusing into a term being renegotiated after delivery. Big companies run on 60 day cycles and some are worth the wait. The point is not that 60 days is always wrong. The point is that a change to an agreed term is a decision both sides make, with something on each side of it, not a setting the client adjusts alone.

Step 2. Anchor the clock to acceptance, not to the ask

Whatever you agree, the clock needs a start date nobody can argue about later, and that date is the day the delivery was accepted, not the day the invoice was re-sent, re-approved, or finally entered into a payment system. State it in your reply in one line: the work was delivered and accepted on this date, the invoice was due on delivery on that date, so any new date is counted from there and named exactly, a calendar date, not a number of days floating free of a start. A floating 60 days restarts every time the paperwork hiccups, which is how 60 becomes 90 without anyone ever lying. An exact date on a shared record cannot quietly restart.

Step 3. Read the two states your delivery can sit in when the ask arrives

The anchor only works if the delivery and its acceptance live on a record both sides can open. The record format is AER-1, published as an IETF Internet-Draft (draft-zambo-aer1-26), and each step carries a verifiable receipt: a receipt proves the saved result was not changed since it was saved. The two public records below show the states a delivery can carry:

Accepted: the decision is on the record

Pending: checked, and still waiting on a decision

An accepted record, 4 of 4 steps checked, decided_by client, release_hint ok_to_release, decided 2026-10-16T14:31:51.146Z in that example, is the strong position: the client side already decided the work was good, on a date, so the payment conversation starts from an accepted delivery and a counted clock. A pending record, 5 of 5 steps checked and release_hint hold, is checked work still waiting for its decision, and there the honest first move is to get the acceptance recorded before discussing dates at all, because terms for a job the client has not formally accepted are a conversation built on fog. Know which state yours is in before you answer.

Step 4. Choose one of three doors, and say it in one message

Door one, agree to the 60 days with conditions: the exact calendar date in writing in the reply thread, a part payment today that shows intent, no new work started until this invoice clears, and the amount and invoice number restated so there is nothing left to re-approve later. Door two, split it: half inside a short window you name, the balance on their 60 day date, both dates exact and written. Splitting tests intent cheaply, because a client who cannot move anything for 60 days on any part of it is telling you something a full agreement would hide. Door three, decline and hold the original term: the invoice stands as agreed, due on delivery, and you ask what is blocking payment today, in those words, because a concrete blocker can often be fixed in a day while a policy cannot. All three doors are professional. The only losing move is the fourth, unlisted one: saying fine in a call, writing nothing down, and discovering the terms two months later.

Step 5. If you agree, make the agreement survive the wait

A 60 day agreement fails in predictable places: the invoice gets lost in a system, the approver changes jobs, the date arrives during a payment freeze nobody mentioned. Cover them in the same written reply, briefly: the exact date and amount, the name of the person confirming it, a short check-in at the halfway point with the invoice and the delivery record attached again, and a line that any further move of the date is a new conversation, not an assumption. Then stop working the debt emotionally. Calendar the date, do the halfway check in one short message, and let the record carry the pressure. If the date passes unpaid, you are no longer negotiating terms, you are collecting an overdue invoice with a dated trail, which is a much stronger conversation, and a different page on this hub.

Step 6. Set terms before the work next time, where they are cheap

Every term is easy before the work starts and expensive after delivery. In the next agreement, state the payment term next to the price, and state what a longer term costs or requires: payment on delivery as standard, longer cycles by written agreement before work starts, with a deposit or staged payments covering the wait. Ask new clients how their payment cycle actually runs during onboarding, not at the invoice, so a 60 day house rule is priced into the job or declined before anyone is owed anything. And keep delivery, acceptance, invoice, and agreed dates on one record, so a terms conversation is always about dates already written down, never about what someone remembers a call covering.

What a record does not settle

A verifiable receipt proves the saved result was not changed since it was saved; it does not prove a client can pay, does not set the terms you should accept for your business, and cannot make payment arrive on an agreed date. The agreement you signed, the acceptance date on the delivery record, and the written terms you settle now are what the conversation stands on. This page is general information, not legal or financial advice.

Frequently asked questions

My client wants 60 days to pay an invoice that was due on delivery. Should I agree?

Only as a renegotiation, in writing, with an exact date and conditions, never silently. The invoice was due on delivery under the terms agreed before the work started, so the clock is already running from the acceptance date on the delivery record. Choose a door and say it in one message: agree to the 60 days with the exact calendar date confirmed in the thread, a part payment today, and no new work until this invoice clears; split it, part inside a short named window and the balance on their date; or decline and ask what is blocking payment today. A genuine slow process survives all three doors fine. What to refuse is the floating version, 60 days from whenever the paperwork finishes moving, because that clock restarts silently and 60 becomes 90 without anyone deciding it.

Does agreeing to longer terms this once set the terms for every future job?

Only if the agreement is left vague. State in the same written reply that the extension covers this invoice only, that your standard term stays due on delivery, and that any longer cycle on a future job is agreed in writing before that work starts, priced or covered with a deposit. Clients mostly honour a boundary that was written at the moment it mattered; what they treat as the new normal is the boundary that was never mentioned, where your silence on job one becomes their expectation on job two.

The client says their company pays everyone at 60 days and there is no choice. What do I do?

Treat the claim as information to verify cheaply, not as a wall. Ask for the exact payment date for this invoice, in writing, and the name of the person confirming it, offer the split as the middle door, and pause new work until the date lands or the first part clears. Large companies do have fixed cycles, and they also make exceptions and part payments when a supplier is calm, dated, and specific. If nothing can move and no date will be named, decide with open eyes: you are choosing to lend this client the invoice amount for an unknown period, so at minimum stop adding new exposure until the first payment proves the cycle is real.

Should I charge a fee or interest for the 60 days?

If your agreement already names a late fee or a longer-terms price, use it exactly as written and show the arithmetic. If it does not, inventing a fee after delivery rarely collects and often costs the relationship; the cleaner trades are the ones in step 4, a part payment now, an exact date, no new work during the wait, and future jobs quoted with the longer cycle priced in or covered by a deposit. The fee belongs in the next agreement, in writing, where it is a term both sides chose rather than a penalty one side announced.

How do I keep payment terms and acceptance dates on one record for the next job?

Run the delivery so the record carries the schedule with the work: the agreed term stated with the stage, the delivery closing as a handover the client accepts with a date, and the invoice tied to that acceptance. When the work runs through Zambo, every step carries a verifiable receipt under AER-1, published as IETF Internet-Draft draft-zambo-aer1-26, so the steps, their dates, and the acceptance state sit on one record both sides can reopen when a terms question arrives. New users get 20 calls and 1 wrap-up free every day, and picking up work in another AI is always free. For $0.99, deliver the next job that way and let the acceptance date start every payment clock: get the Day Pass. A Day Pass is unlimited for 24 hours, no subscription. Ongoing use is the Zambo Pass at $29 a month or $290 a year, and $19 a month for $ZAMBO holders, which adds private handover links, your branding, and the approval record as PDF and JSON files.

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