Purchase Authorisation Form: What to Include and How to Use It

A purchase authorisation form is the internal document that asks someone with authority to approve a spend before money leaves the business. It names the requester, describes what is being bought, states the cost and budget, and ends with a signed decision. Once approved, it usually becomes a purchase order sent to the supplier. This guide covers the fields to include, how approval limits work, a template layout you can copy, and how to run the whole thing online with a signature and an audit trail.

TL;DR

• A purchase authorisation form (also called a purchase approval form or purchase requisition) is an internal gate. The purchase order is the separate document that goes to the vendor.
• Include the requester, item lines with quantities and prices, budget codes, a business justification, a suggested vendor and a space for required approvals.
• Route by value, department or risk, and keep the requester and the approver as two different people.
• Record who approved, when and why, so the approved request can be converted into a purchase order cleanly.
• A form-first digital workflow beats a PDF passed around by email, because the decision and signature are captured in one place.

Table of Contents

• What a purchase authorisation form is (and what it is not)
• Who submits, who approves
• What to include on the form
• Set approval levels by value and risk
• From approval to purchase order
• Why paper and email approvals fall short
• Turn the form into a workflow
• Run your approvals in KSign
• FAQ
• Sources

What a purchase authorisation form is (and what it is not)

People use several names for the same idea: purchase authorisation form, purchase approval form, purchase request, purchase requisition. In practice they describe an internal document, typically a form, that an employee or department submits to ask for approval to buy something before a purchase order is issued. Amazon Business describes a purchase requisition in just these terms.

The distinction that matters is between the internal request and the external order. CIPS, the professional body for procurement, explains that a requisition is an internal gate, while a purchase order is the external document sent to a supplier, confirming the purchase and acting as a binding agreement. Both are essential, but they do different jobs.

That gives you a simple mental model:

1. Requisition or authorisation form: “May I buy this?” Internal, answered by a manager or finance.
2. Purchase order: “Please supply this.” External, sent to the vendor once approval is complete.

There is a small nuance in scope too. A requisition can consolidate items from several suppliers, whereas a purchase request is typically limited to a single vendor, according to Amazon Business. If you buy from several vendors, decide up front whether you want one form per vendor or one form with many lines.

One more thing to keep separate: a purchase authorisation form is not a credit card authorisation form. The latter lets a third party charge a customer’s card. Our topic is the form your own team uses to get a spend approved.

Who submits, who approves

The basic roles are simple. A requestor creates the requisition, and a designated supervisory or managerial approver reviews and authorises it. At California State University, Dominguez Hills, the approver budget-checks the requisition before it moves on to Procurement and Contracts.

The same university policy points to a control worth copying in any business: segregation of duties. A single user cannot be both the requester creating a requisition and the approver authorising it. In a three-person business this feels heavy, but the principle still works: the person who wants the purchase should not be the only person who signs it off. If you are a sole owner, the equivalent is a second set of eyes, such as your bookkeeper or a business partner, on anything above a limit you set.

Software systems enforce the same logic. One enterprise procurement system describes how purchase authorisation checks defined rules and retrieves routing templates when a requisition line or order is released, and the line cannot proceed until it is authorised. You do not need enterprise software to get that behaviour, but you do need the rule to be written down.

What to include on the form

A good form is short enough that people actually complete it and detailed enough that an approver can say yes or no without chasing anyone. The most thorough public example is the US Department of Agriculture’s AD-700 purchase request form (December 2024 version). It asks for the requester’s name, phone and email, a technical contact, the shipping address, the sources checked, line-item descriptions, quantities and prices, accounting and budget codes, recommended vendors, attachments and the required approvals.

A government form will be heavier than a small business needs, but the skeleton transfers. Commercial guidance lines up: NetSuite lists an item description, quantity, estimated price, suggested vendor, business justification and the requester’s department as typical fields. Amazon Business adds that a well-designed form captures enough detail, including total estimated costs and budget codes, for approvers to decide with confidence.

Here is a practical field list for a small business:

A clear business reason is not decoration. NetSuite notes that stating the rationale and expected benefit helps reviewers verify legitimacy and budget fit. And structured data pays off later: Amazon Business points out that complete, structured requisition data lets an organisation analyse spending patterns, spot savings and plan future budgets.

A template layout you can copy

Use this order on the page. People complete forms top to bottom, so put what the approver needs first.

1. Header: form title, request number, date submitted.
2. Requester block: name, department or job, contact details.
3. What and how much: a table of lines, then an estimated total.
4. Budget: cost code, job or project, whether the amount is already in the budget.
5. Vendor and quotes: preferred supplier, attached quotes, reason.
6. Justification: two or three sentences.
7. Approval block: approve, reject or send back, with comments, name, signature and date.

The US General Services Administration publishes sample, non-mandatory templates for purchase pre-approval, approval requests and blanket approval authority for use with government purchase cards. They are built for federal card programs, so treat them as a reference for structure rather than something to copy word for word.

Set approval levels by value and risk

Not every purchase deserves the same scrutiny. A box of consumables and a new vehicle should not take the same route. Procurify’s guidance says approval paths can vary with purchase value, department, vendor or risk, and may need input from Finance, IT, Legal or executives. The same source suggests layered approvals for high-value transactions, balanced so they do not slow the business without reason.

Universities show what this looks like in practice. The University of Illinois describes purchase approval workflows that route requests by criteria such as organisation code, dollar thresholds, the type of item or the use of grant funds. Michigan State University requires formal, documented price or cost analysis for purchases between $25,000 and $249,999.99, to show the price is fair and reasonable. Those are institutional numbers, not rules for your business, but they show the pattern: the bigger the commitment, the more evidence and the more signatures.

Amazon Business describes the same idea as escalation rules: larger commitments trigger extra levels, such as signatures from department heads or finance.

A simple tier table for a small service business might look like this. The dollar amounts are examples only, so set your own.

Risk is the dimension people forget. A low-dollar purchase can still carry high consequences when it involves regulated or hazardous work. Cornelius Wrecking’s piece on putting OSHA surveys in writing shows how a demolition contract spells out safety obligations rather than leaving them implied. The lesson for an approval form is the same: when a purchase has a safety or compliance angle, add a required field for it and a named reviewer, instead of relying on the requester to remember.

Keep approvals moving

Approval systems fail when requests sit unread. Amazon Business notes that effective workflows often include configurable response windows, so a request does not stall, and a predefined hierarchy that removes doubt about who owns the decision. For a small team, that can be as plain as: “The owner replies within one business day, otherwise the request goes to the office manager.”

And when the answer is no, say why. NetSuite advises that a rejected requester should receive a clear explanation from the reviewer. A “rejected” with a one-line reason saves a second round of questions and teaches people what a strong request looks like.

From approval to purchase order

Once the required approvals are complete, the request can be converted into a purchase order. Procurify adds that an effective approval system records who approved each purchase and why. That record is what you will want months later when an invoice arrives and someone asks who agreed to it.

The handover is where internal and external documents meet. The form is the internal decision. The purchase order carries the approved details to the supplier. If you hire a contractor for a job such as a site clean-up, your approval form might cover the budget and quote comparison, while the order to the supplier covers scope and price. A guide on junk removal for contractors shows the kind of volume, safety and salvage details worth settling before you commit, which is exactly the content an approver wants attached to the request.

Keep these items together in one record:

• the submitted form and its attachments;
• each approver’s decision, comments and signature with a timestamp;
• the resulting purchase order number;
• the supplier’s confirmation and later invoice.

If you manage properties or run recurring vendor work, consistent paperwork matters in the same way. RentrIQ’s story on vendor onboarding documents shows how a small set of standard documents can keep vendor relationships from dropping off, and the same discipline applies to purchase approvals: a few standard documents, collected every time.

Why paper and email approvals fall short

Most small businesses begin with a Word or PDF template, filled in and emailed. It works until volume grows. Common failure points:

• Versions multiply. Three people edit three copies and nobody knows which is current.
• Approvals live in inboxes. A “looks good” email is hard to find and does not say what exactly was approved.
• Missing fields. Free-form documents let people skip budget codes or quotes.
• No routing. Someone has to remember to forward a high-value request to the second approver.
• No clean record. At audit or dispute time, you reconstruct the story from messages.

A form that enforces required fields, routes by value and captures a signature fixes all five. It also means the approver can decide from a phone, between jobs, which matters for tradies, cleaners and other field-based teams.

Turn the form into a workflow

The steps to run purchase approvals online are straightforward:

1. Build the form with required fields for item lines, cost, budget code and justification.
2. Add routing rules so low-value requests go to one approver and high-value ones add a second.
3. Send for signature so each approval is a signed, timestamped decision, not a reply.
4. Store the result with its audit trail alongside the purchase order.
5. Review monthly: which requests were delayed, which were rejected and why, and whether your limits still fit.

The same approach also suits approvals that face customers, such as job authorisations and variations. We have written about digital job approval on mobile, a change order template for contractors and building an invoice approval workflow, and the logic is shared: capture the information first, then the decision, then the signature.

Our view: the form should come first

We built KSign around a simple belief: approval problems start long before the signature. Most e-signature tools assume you already have a finished document to upload. That works for a contract, but it leaves the hardest part, collecting the right information in the right shape, to email and guesswork.

For purchase authorisation, that means the form is the product. When required fields, budget codes and justification are captured up front, the approver sees a complete request and the decision is quick. When the signature and the record sit in the same workflow, you can show who approved what, and when, without digging through inboxes.

Our approach is designed to keep this practical for small businesses: mobile-friendly, repeatable and priced transparently, rather than built around heavy enterprise contract systems. Verifiable records, a clear audit trail and an approval that cannot be quietly edited afterwards are what give a team confidence in its own paperwork.

Josh

Run your approvals in KSign

If you want this workflow without building it from scratch, KSign lets you create guided forms, route them for signature and keep the signed record with its audit trail. You can start from approval workflows, build the form with web forms software and collect decisions through eSignatures. Plans are published on the pricing page: Standard is A$24 per month per seat, Professional is A$40 per month per seat, and Enterprise has no published price.

If your purchases also involve customer payments or deposits, see how we handle quote approval and payment in a single flow.

FAQ

What is the difference between a purchase authorisation form and a purchase order?

The authorisation form (or requisition) is internal: an employee asks for approval to buy. The purchase order is external: it goes to the supplier after approval and acts as a binding agreement, as CIPS explains. Many businesses convert the approved form directly into the order.

Who should sign a purchase approval form?

A supervisor or manager with authority over the budget, and a second approver for higher values or risk. The requester should not be the only approver, a principle set out in university purchasing policy. Name the approver for each tier in writing.

Can I use a free purchase authorisation template?

Yes, as a starting point. Public examples such as the GSA sample templates show structure, but they are written for government card programs. Adapt the fields, limits and approval block to your own business, then test it on a few real requests.

What should happen when a request is rejected?

The requester should get a clear reason, as NetSuite advises. Keep the rejected form on record with the comment, so the decision is traceable and the requester can resubmit with what was missing.

Sources

• Purchase Requisition | CIPS
• What Is a Purchase Requisition? Process & Best Practices | Amazon Business
• The 2026 guide to the procure-to-pay process | Amazon Business
• Purchasing Policy | CSU Dominguez Hills
• Purchase Authorization | IFS documentation
• USDA AD-700 purchase request form
• What Is a Purchase Requisition? | NetSuite
• Purchase Business Line Publications | GSA SmartPay
• Purchase Approval Workflows: Examples & Best Practices | Procurify
• Procurement guide | Michigan State University
• Create a Purchase Requisition Process Report | University of Illinois
• PO approval workflow | Amazon Business
• U.S. Demolition Contract Terms | Cornelius Wrecking
• Junk Removal for Contractors | Easy Scrap
• Vendor Portal Onboarding | RentrIQ

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