Structuring Invoices for Corporate Clients
In the consulting world, an unclear invoice is the fastest way to delay payment. Corporate Accounts Payable (AP) departments follow strict protocols. Here is how to ensure your invoice gets approved immediately in 2026.
1. The "PO Number" Imperative
Large enterprises often operate on a "No PO, No Pay" policy. A Purchase Order (PO) Number connects your invoice to an approved budget. Sending an invoice without this reference typically results in automatic rejection. Tip: Always request the PO Number from your project sponsor before generating your first invoice.
2. Hourly vs. Retainer vs. Project
This generator supports all three standard consulting billing models:
- Time & Materials (T&M): List your hours and rate explicitly. Attach a timesheet if required.
- Retainers: Use a single line item (Quantity: 1) described as "Monthly Retainer - [Month]". This signifies a recurring reservation of availability.
- Fixed Price Milestones: Bill upon completion of deliverables (e.g., "Phase 1: Strategy Delivery").
3. Handling "Scope Creep" & Expenses
Additional work outside the original contract (Scope Creep) should be listed as a separate line item labeled "Additional Services (Authorized via Email [Date])". Similarly, Reimbursable Expenses (flight, hotel, software) must be separated from labor costs to ensure accurate tax handling.