Buying research peptides on an institutional purchase order: which suppliers accept POs

Why the PO question comes first

University and company buyers often cannot pay a new supplier by card at checkout. A purchase order needs a supplier willing to issue a quote, accept the PO, invoice against it and wait for payment terms. If a supplier will not do that, the order usually has to go through a card holder or a distributor, and that changes the paperwork you will have afterwards.

Below is what each supplier published on 30 October 2026. Where a page said nothing, we say so rather than guess; silence is not a refusal, but it means you need a written answer.

What each supplier publishes

Peptides EU's FAQ says to contact its team with the institution details for purchase orders or bulk orders. [1] Its terms do not address purchase orders or invoices and say an order is confirmed only after successful payment processing, so ask whether a PO order still requires payment before dispatch. [2]

OMNI's wholesale page, when checked, showed only a research-access eligibility check for verified laboratories, universities and independent researchers and did not mention purchase orders, net terms, invoices or quotes. [3] Its terms say payment is due at the time of purchase. [4] Evolve's FAQ says wholesale orders over 15 vials are handled by email with personalised pricing and that it currently serves only the United States; it does not mention purchase orders. [5]

Among catalog and custom suppliers, Bachem's FAQ says it accepts wire transfers or purchase orders with net payment terms required, that prepayment may be required depending on your company's payment agreements, and that it does not accept credit cards. [6] Its general conditions say orders are binding only when Bachem confirms them in writing and invoices are payable within 30 days. [7] Cayman's order terms give net 30 days, ask that confirming purchase orders be clearly marked to avoid duplication, and accept US funds, Visa, Mastercard or American Express. [8] GenScript's peptide synthesis page directs buyers to an online quote form, email or phone and does not mention purchase orders. [9]

Vendor setup: documents procurement usually asks for

Before a PO can be issued, most procurement offices set up the supplier as a vendor. Ask for these items in one email so you do not lose a week to back-and-forth. Our supplier document manifest lists the quality documents to file once the material arrives.

• Formal quotation on letterhead, with prices, currency, validity and delivery terms (Incoterms).
• US buyers: a Form W-9, which the IRS says is used to provide a correct taxpayer identification number to a payer that must file information returns. [11]
• EU buyers: the supplier's VAT number, and your institution's VAT number on the order. Your Europe says a business selling goods sent to a business in another EU country does not charge VAT if the customer has a valid EU VAT number, which can be checked in VIES. [12]
• Terms of sale, including the defect-notification window, for example Bachem's 8 days and Cayman's 30 days. [7] [8]
• Sample or lot-specific certificate of analysis and the safety data sheet.
• Bank details on the supplier's letterhead, confirmed by phone before the first payment.

Notification windows that start when goods arrive

PO terms often differ from storefront terms in how long you have to report a problem, and the clock usually starts at delivery, not when the invoice is approved. Make sure the person receiving the goods knows the window.

Worked example: raising a PO for a first order

A lab manager needs one catalog peptide and one item from a research storefront. For the catalog item, she requests a quote, attaches it to the PO, and notes the 8-day defect window from the seller's terms so the receiving technician checks the parcel within a week. [7] For the storefront, she emails Peptides EU with the institution's details as its FAQ asks and requests a written answer on whether it will invoice against a PO or still requires payment before dispatch. [1] [2] If the answer is prepayment only, she routes the order through the department card instead and records the reason on the file.

Questions to send before the PO

Send these in writing and keep the replies with the PO.

• Will you accept our purchase order and invoice against it, and on what payment terms?
• Do you require prepayment for a first order?
• Which entity, address and VAT or tax number will appear on the invoice?
• Will the certificate of analysis be lot-specific, and will the lot number match the vial label?
• What is your window for reporting damaged or incorrect goods, and to whom?