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Big companies pay a process, not a person. Here is how to work the process.

A delayed invoice at a big company is almost never a decision about you. It is a missing field, an approval nobody has given, or a payment run your invoice never made it into. Each of those has a specific fix, and the fixes are boring, which is why they work.

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Updated October 22, 2026. The two delivery records quoted below are real and public, with their client decision states read back from the live service on publication day.

Step 1. Find the missing item before you chase anyone

Ask accounts one precise question: what exactly is missing or unapproved on this invoice today. The usual answers are a short list. No purchase order number, or the number never made it onto the invoice. Vendor setup never completed, so you do not exist as a payable supplier yet. A name, tax, or bank detail that does not match what onboarding registered. An invoice sent to your contact's inbox instead of the payments portal, so it was never in the system at all. Fix every gap in one pass, resubmit once, and get written confirmation that the invoice is now complete and in the queue. A complete invoice with a confirmation beats five polite follow-ups about an incomplete one.

Step 2. Get the approval from the person who ordered the work

Accounts departments pay approved invoices. Approval belongs to the person who ordered or received the work, and it is the step most delays actually sit in, because that person is busy and approving your invoice is nobody's deadline but yours. Make approval a one-minute job: send them the delivery record, the amount, and the exact button, link, or reply their system needs. The record matters here. An approver asked to confirm work they can see, step by step, with an acceptance state in front of them approves in one sitting. An approver asked to confirm work from memory schedules it for later, and later is where your month goes.

Step 3. Put the delivery on a record the approver can decide on

The record format is AER-1, published as an IETF Internet-Draft (draft-zambo-aer1-24). Each step of the work is saved as it happens and carries a verifiable receipt: a receipt proves the saved result was not changed since it was saved. The approver receives one handover link and accepts or flags the work, and that decision is recorded with who decided and when. The two public records below show the two states:

Accepted: the decision is on the record

Pending: checked, and still waiting on a decision

Read the two cards together. The accepted record is the state accounts can pay against: work checked, 4 of 4 steps on the record, decision made by the client and dated. The pending record shows the other state honestly: all 5 steps checked and saved, and the decision itself still owed. If your invoice is stuck, it is very often sitting behind a pending decision like that one, and no amount of emailing accounts moves a decision that belongs to your approver.

Step 4. Learn the machine: terms, run days, and your reference number

Three facts turn follow-ups from begging into bookkeeping. Their payment terms, counted from approval, not from your invoice date: net 30 from approval is a different date from net 30 from invoice, and the difference is usually your missing month. Their payment run days: many companies pay once or twice a month, so an invoice approved the day after a run waits a full cycle even when everything is right. And your reference: the ticket, case, or invoice number their system assigned, quoted in every message so anyone can pull your invoice up in seconds. With those three facts you can name the exact run your payment belongs in, and ask about that run by date instead of asking whether there is any news.

Step 5. Agree the date in writing, then escalate through your sponsor

End the process work with one written line from accounts or your approver: this invoice will be paid on this date. If the date passes, escalate inside the company, not at it. Your sponsor is the person whose project the work served; send them the short file: the agreement, the accepted delivery record, the complete invoice, the agreed date, and the fact that it passed. Internal escalation works because it moves the invoice from a queue nobody owns to a person whose own work is attached to it. Stay factual and stay kind: the goal is a champion inside the building, and people champion suppliers who make the problem easy to forward.

Step 6. Protect the next cycle while you wait

Pause new deliverables politely once an agreed date has slipped, and say it as capacity, not punishment: the current invoice is past its agreed date, so new work is scheduled once it clears. Keep delivering nothing for free into a process that has already shown you its speed. And when the payment lands, note the real cycle length, approval wait plus terms plus run wait, and price it into the next engagement: stage invoices, a deposit, or terms that start at approval. Big companies are good clients at the wrong speed. The speed is manageable once it is measured.

What a record does not settle

A verifiable receipt proves the saved result was not changed since it was saved; it does not prove the work was good, does not approve your invoice inside the client's system, and cannot move a payment run. Approval, terms, and run dates are the client's process. This page is general information, not legal advice.

Frequently asked questions

How do I get a big company to pay my invoice when their accounts department keeps delaying it?

Stop chasing the invoice and start working their process, because a big company pays invoices that clear a checklist, not invoices that are chased hardest. First find the missing item: a purchase order number you never got, vendor setup forms never filed, a wrong legal name or tax detail, or an invoice sent to a person instead of the payments system. Fix it in one pass and get written confirmation that the invoice is now complete. Second, get approval from the person who ordered the work, in their system, because accounts cannot pay an unapproved invoice no matter how often you email them. Third, learn the machine: their payment terms counted from approval, their payment run days, and the reference or ticket number for your invoice, so every follow-up cites a fact instead of asking for news. Fourth, agree the exact payment date in writing. If that date passes, escalate through your sponsor inside the company, the person whose project the work served, with the full record attached: agreement, approved delivery, invoice, and the missed date.

Why do big companies take so long to pay small suppliers?

Usually process, sometimes policy, rarely personal. Process: your invoice is one of thousands, handled by people who never saw the work, and it moves only when every field their system wants is present and a named approver has cleared it. Any missing item parks it silently, because nobody is assigned to tell you. Policy: many large companies set long standard payment terms and pay on fixed run days, so even a perfect invoice waits for its slot. Cash management sits behind both: delaying supplier payments is free financing, and a small supplier with no dates, no reference numbers, and no internal sponsor is the easiest invoice in the pile to leave until next week. None of that is fixed by louder reminders. All of it is fixed by making your invoice the one that is complete, approved, referenced, and attached to a date someone inside has agreed in writing.

Who inside a big company can actually get my invoice paid?

Two different people, and you need both. The approver is the person who ordered or received the work: only they can confirm the work arrived and was accepted, and in most systems accounts will not move without that approval. The accounts contact is the person who can tell you the invoice state, the payment terms being applied, and the run it is scheduled in. The mistake is working only one of them: accounts cannot approve work they never saw, and your approver cannot cut a payment from their desk. Ask each one for their half, in writing: approval confirmed from the approver, with the delivery record in front of them so approval takes one look, and the scheduled run date from accounts, with a reference number for the invoice. When both halves exist and a date still slips, your approver becomes your escalation route, because they carry internal weight you do not.

What should be on my invoice so accounts cannot bounce it back?

Everything their checklist asks for, in the exact form they ask for it: your legal business name and theirs, the purchase order number on the invoice itself, your vendor or supplier number if they issued one, the invoice number and date, the work period or delivery date, the amount broken down the way the order breaks it down, your tax details in the form their onboarding requested, and your payment details exactly as registered. Attach the delivery evidence the approver needs: the delivery record link and its acceptance state, so approval is a check, not an investigation. Then confirm receipt in their system, not just in an inbox: an invoice sitting in a person's email is not in the process at all. Most bounced invoices fail on one missing field, and the bounce costs a full payment cycle, which is why the checklist is worth doing before the invoice is due, not after.

How do I set up the next big-company job so payment is not delayed?

Do the process work before the work starts. Get the purchase order number before you begin, finish vendor onboarding while the project runs rather than after it, agree in writing who approves delivery and what they approve it on, and invoice in stages on long jobs so no single delayed invoice holds the whole project fee. Deliver each stage as a record the approver can check and accept in one sitting, because approval speed is where small suppliers lose their month. When the work runs through Zambo, every step is saved as it happens and the approver gets one handover link to accept or flag, with the decision recorded. For $0.99, deliver big-company work on a record their approver can accept in one look, so approval stops being the delay: get the Day Pass. A Day Pass covers 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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