Purchase Order Format: Free GST-Compliant Excel & Word Template
A complete guide to purchase order format in India — mandatory fields, GST on PO, vendor management, and a free Excel and Word template download for 2026.
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Key takeaways
- A purchase order is the buyer's offer; it becomes a binding contract once the vendor accepts, and it precedes the tax invoice.
- GST liability arises at the tax invoice, not the PO, but the PO should state the HSN code, rate and CGST/SGST or IGST split.
- Number POs sequentially per financial year (PO/2025-26/001) and never reuse a number; duplicates are an audit red flag.
- Match PO, goods receipt note and vendor invoice before paying, and keep POs for six years.
What Is a Purchase Order and Why Does Format Matter?
A purchase order (PO) is a formal document issued by a buyer to a seller, authorizing the purchase of specific goods or services at an agreed price. Unlike an invoice — which the seller issues after delivering goods — a purchase order comes first. It creates a legally binding contract once the seller acknowledges it.
In India, purchase orders are used by businesses of all sizes, but their importance increases sharply for GST-registered businesses. Here is why the format matters:
For input tax credit: If you are a GST-registered buyer, every purchase that you want to claim as a business expense or input tax credit must be traceable to a PO. Your auditors will ask for PO documentation during statutory audits. A missing or informal PO (like a WhatsApp message) creates gaps in the paper trail.
For vendor disputes: A PO locks in the price, quantity, delivery date, and payment terms. If the vendor delivers short or raises a higher invoice, the PO is your reference point. Without a formal PO, disputes are difficult to resolve because there is no signed baseline agreement.
For GST compliance: When a vendor generates a tax invoice against your PO, they must reference the PO number on the invoice in many business setups. This allows your accounts team to match the PO, goods receipt, and invoice — the three-way match that prevents fraud and duplicate payments.
This guide covers what a proper purchase order format includes, how GST applies to purchase orders, and how to create one using the free PO generator from myBillPlease.
Mandatory Fields in a GST-Compliant Purchase Order
These fields make a PO legally defensible and GST-audit ready
- PO number — unique sequential identifier (e.g., PO-2026-0042). Never reuse numbers.
- PO date — date the purchase order was issued by the buyer
- Buyer's name, GSTIN, and registered address
- Vendor's name, GSTIN, and registered address
- Delivery address — where goods are to be shipped (may differ from buyer's registered address)
- Expected delivery date — or delivery window (e.g., within 7 working days of PO date)
- Item description — clear name of each product or service being ordered
- HSN code or SAC code — for GST classification
- Quantity and unit of measurement (Nos, Kg, Ltr, Box, etc.)
- Unit price (exclusive of GST) — the agreed price per unit before taxes
- GST rate applicable — 0%, 5%, 18%, or 40% per the current GST 2.0 structure
- Tax amount breakdown — CGST + SGST (intra-state) or IGST (inter-state)
- Total PO value — including all taxes and any freight/handling charges
- Payment terms — e.g., 30 days from invoice date, or advance + balance on delivery
- Authorized signatory — name and signature of the buyer's authorized person
- Terms and conditions — delivery penalties, rejection policy, warranty terms
How GST Works on a Purchase Order
A purchase order itself does not create a GST liability. The liability arises when the vendor delivers goods or services and raises a tax invoice. However, the GST rate shown on the PO is critical because it sets the mutual understanding between buyer and vendor before the supply happens.
Intra-state purchases: If the vendor is in the same state as your delivery address, CGST and SGST apply. Each is half of the total GST rate. For an 18% GST item, CGST = 9% and SGST = 9%.
Inter-state purchases: If the vendor ships from a different state to your delivery address, IGST applies at the full rate. An item at 18% GST would show IGST 18% on both the PO and the final invoice.
Which rate to use in 2026: After the GST 2.0 reform effective September 22, 2025, the applicable rates are 0%, 5%, 18%, and 40%. If your PO references an old 12% or 28% rate for items ordered before the cutoff, those rates apply for the old orders. New POs must reflect the updated rates. Always confirm the HSN code and current rate before issuing a PO — the vendor will invoice at whatever rate the PO specifies.
Advance payments on PO: If you pay an advance against a PO (e.g., 30% advance before manufacturing), the vendor must issue a receipt voucher at the time of receiving the advance. The remaining GST is settled when the final tax invoice is issued. Do not expect the PO itself to serve as a tax document.
Import POs: For purchases from foreign vendors, there is no CGST or SGST on the PO. Import of goods attracts IGST at the port of entry (paid as Integrated GST on imports), which you may be able to claim as ITC. Import POs follow a different format and reference INR values at the declared customs exchange rate.
PO Approval Workflow — How Indian Businesses Handle It
For small businesses (fewer than 10 employees), a purchase order is often created and approved by the same person — the owner. But as businesses grow, a proper approval workflow prevents unauthorized spending and keeps the finance team in control.
Single-approver workflow (small business): The person who needs the goods creates a PO request, the owner reviews and signs it, and the signed PDF is sent to the vendor. The vendor acknowledges receipt, and the PO is filed.
Two-level approval (mid-size business): The department head creates and approves POs under a certain value limit (e.g., up to Rs 50,000). POs above Rs 50,000 require the finance manager's approval. This is the most common setup in Indian trading companies and manufacturing units.
Three-level approval (large business): Procurement team creates the PO → Department head approves → CFO or finance controller approves for high-value orders (e.g., above Rs 5 lakh). ERP systems like SAP or Tally handle this digitally.
PO number formats used in India:
Most businesses use one of these conventions: PO/2026/001 (financial year + sequential), or PO-MAR-26-001 (month + year + sequence), or simply PO-0042 (rolling number). Whatever format you choose, never reset the sequence within a financial year — this is important for GST audit trail purposes.
The myBillPlease PO generator auto-generates sequential PO numbers and lets you set the format. You can also configure approval workflows and email POs directly to vendors.
Purchase Order Best Practices for Vendor Management
How We Built the PO Generator in myBillPlease
We added the purchase order generator to myBillPlease because our users kept telling us the same story: they were emailing informal POs as Word documents, vendors were invoicing at different quantities or prices, and reconciling at month-end was painful.
The myBillPlease PO generator solves the format problem in under 2 minutes. Enter your vendor details (stored if they are already in your contacts), add line items with HSN codes and GST rates, and the system calculates the correct CGST/SGST or IGST based on the delivery state. The PO is generated as a professional PDF and can be emailed to the vendor directly.
When the vendor sends their invoice, you can match it against the saved PO in the system — we show you any discrepancies in price, quantity, or tax before you approve payment. Try the free PO tool — no account required for the first 5 POs.
Frequently asked questions
- Is a purchase order legally binding in India?
- A purchase order becomes legally binding once the vendor acknowledges or accepts it — either by signing, by sending a formal acceptance, or by starting to fulfill the order. An unacknowledged PO sent by the buyer is only an offer to purchase. Once accepted, it forms a contract under the Indian Contract Act, 1872. Both parties are bound by the terms stated in the PO — price, quantity, delivery date, and payment terms. If the vendor delivers goods different from what the PO specifies, the buyer can legally reject them or demand a credit note.
- Does GST apply at the time of purchase order or invoice?
- GST liability arises at the time of supply — which is the earlier of the date of invoice or the date of receipt of payment. A purchase order is not a supply document; it is a commitment to buy. So GST does not apply when the PO is issued. GST becomes applicable when the vendor delivers the goods or services and raises a tax invoice. If an advance is paid against the PO before delivery, the vendor must issue a receipt voucher at that point, and the final GST settles on the tax invoice issued at the time of actual supply.
- What is the difference between a purchase order and a tax invoice?
- A purchase order is issued by the buyer before goods are received — it authorizes the purchase and locks the terms. A tax invoice is issued by the seller after goods are supplied or services are rendered — it creates the GST liability and enables the buyer to claim input tax credit. The flow is: buyer issues PO → seller acknowledges PO → seller delivers goods → seller raises tax invoice referencing the PO number → buyer verifies and makes payment. Both documents are required for a complete audit trail in GST compliance.
- What HSN code should I put on a purchase order?
- The HSN (Harmonised System of Nomenclature) code on a purchase order should match the expected classification of the goods you are buying. You can determine the HSN code using the CBIC HSN directory or the myBillPlease GST calculator with HSN lookup. The code on the PO is an estimate — the vendor will confirm the final HSN on their tax invoice. If the vendor uses a different HSN code on their invoice, it may affect the GST rate charged. Always cross-check: the HSN code on the PO should match the vendor's final invoice for a clean three-way match.
- How should I number purchase orders for a financial year?
- Indian businesses typically reset purchase order numbering at the start of each financial year (April 1). A standard format includes the financial year and sequential number: PO/2025-26/001. This makes it easy to identify which financial year a PO belongs to during audits. Some businesses also add a vendor code: PO/2025-26/VND-012/003 for the third PO issued to vendor 012. Whatever format you choose, never issue two POs with the same number in the same year — duplicates are a major red flag during GST audits and statutory audits alike.
- Can I use a purchase order as proof of business expense for income tax?
- A purchase order alone is not sufficient proof of a business expense for income tax purposes. You need the complete chain: purchase order, goods receipt note (GRN) confirming delivery, and the vendor's tax invoice. The tax invoice is the primary document for claiming the expense deduction and GST input tax credit. However, purchase orders are essential supporting documents during income tax scrutiny — they prove the commercial rationale for the purchase and that it was properly authorized before payment. Keep POs along with corresponding invoices and payment records for at least 6 years.
