A chemical purchase order is your instruction to buy; a chemical proforma invoice is the supplier's offer of those goods on stated terms, issued before shipment. The proforma should mirror the order exactly, and any difference must be settled before you pay.
A chemical reorder is where problems creep in, because people assume last time's terms still apply. Lock them in writing from the first order.
What should a chemical purchase order contain?
The order should be complete enough that a stranger could fulfil it:
- Product name, grade, CAS number where relevant, and the specification or data sheet reference with its revision.
- Quantity, with a tolerance, and the unit, such as tonnes net.
- Packaging: drum type, IBC, liner, net weight per package and pallet arrangement.
- Incoterm and named place, as in FOB, CIF or DAP.
- Payment terms, shipment date and the documents required.
- Acceptance rules: sampling method, tests and the limits that trigger rejection.
How should you read the proforma invoice?
Compare it with your order line by line. Check the name and address of the seller, the product description, the quantity, the Incoterm, the packaging and the payment terms. Make sure the bank account is in the company's name.
Many disputes start from a proforma that quietly changed a detail, such as a grade name or a different tolerance. The proforma is often the base for the bank and customs paperwork, so mismatches ripple through. The documents your broker needs are in the document pack your customs broker will ask for.
Keep a simple log for each product: specification revision, approved sample reference, packaging, supplier site and the date of each change. When a supplier proposes an alternative, such as a different drum liner, a new raw material source or a transfer to another plant, the log shows what you have already approved. Without it, small changes build up unnoticed until the product behaves differently in your process, and then nobody can say when it started.
Which terms belong in a contract instead?
Some terms are too long for a PO, such as claim procedures, liability, confidentiality and governing law. Put these into a framework agreement and refer to it from each order. See what a chemical purchase contract should include.
Have a lawyer review the framework terms, especially if you operate across several countries.
One more point: keep every version. If the proforma is revised, the revision date and the changes should be clear, and the order should be updated or confirmed in writing. Verbal agreements on a call, however friendly, are hard to enforce when a lot arrives off-specification.
How do you keep reorders consistent?
Quote the same specification revision, the same packaging and the same tests on every order, and keep the approved sample on both sides. If the supplier proposes any change in raw material, process or site, require notice and a new approval.
Compare each COA with the last one. Slow drift is easy to miss in a single document but obvious in a table of results across batches. This is the failure described in why quality drops after the first container, and specialty chemical batch consistency shows how to track it.
Next step
Build one order template and use it every time. We check documents against the order, have lots tested and supervise loading, so what ships is what you asked for. Book a free sourcing review and bring your current PO and proforma.