Invoice your client for a month of freelance work

If you bill an organisation for a few days or hours each month, the useful routine is small: agree the work, put the right reference on the invoice, send it and follow payment. Your customer is the client organisation named in your agreement; check its actual billing entity even if your day-to-day contact works elsewhere in the group.

This guide covers a Belgian supplier using OrdoGrid's Peppol send flow. For an initial setup, follow your first Peppol invoice first.

Confirm the month before invoicing

Review your contract or agreed scope and the work accepted for that period. Keep the confirmed days/hours or other basis for billing. Check who can confirm a timesheet and whether that confirmation is needed before the client processes an invoice.

Ask the billing contact for the legal client name, VAT identifier, billing address and purchase-order number or buyer reference. A project name or the name of your contact may not be the reference their accounts-payable team expects. Confirm the invoice date, payment terms and currency from the actual agreement.

If the client has not approved disputed time, resolve that amount rather than quietly rounding it into another line.

Turn the agreement into clear lines

For example, you and the client agreed 8 days at €600 per day in EUR for September. The amount before tax is €4,800. A useful description is “Consulting services — September 2026 — 8 agreed days”.

That example does not determine your VAT treatment. Use the treatment your accountant has confirmed for your business and this transaction. If you bill hours, use the agreed hourly rate and actual approved hours. If you bill a fixed fee, describe the period or deliverable and use the agreed fee rather than invented day counts.

Keep expenses separate if the agreement calls for separate reimbursement. Check supporting receipts and how those expenses should be described and taxed before adding them. A saved timesheet or client confirmation helps answer questions later; only attach documents the client needs.

Prepare the invoice in OrdoGrid

Open Factures → Nouvelle facture and select the client. Check their details again if the company, address or reference has changed.

Complete the invoice date, due date, currency and purchase reference. Review the proposed invoice number. Enter descriptions, quantities, unit prices and the accountant-confirmed VAT treatment. Check whether prices include VAT and read the subtotal, tax and final total in Totaux.

Preview the PDF. Could the client identify the month, work and reference without calling you? Save the invoice and keep its number. If saving returns you to the list, reopen that same document.

Send once and check the result

Choose Envoyer, check the Peppol option and any Email copy, then confirm with Sauvegarder & Envoyer. The panel checks the client's Peppol availability and may direct you to complete authorisation.

Find the invoice in Peppol → Outbox and refresh its status. Do not create a replacement invoice because the response is slow or the message is still processing. An uncertain result needs clarification before another send.

Network delivery does not prove approval or payment, as OpenPeppol's response specification explains. Follow the agreed due date. Record payment only when you have confirmation that the money arrived.

Next month, use the agreement as your checklist

Create a new invoice for the new period. You can select the stored client again, then enter the current month's work, reference, dates and amounts. Do not edit last month's issued invoice to make this month's bill.

Check whether the purchase-order number still applies and whether the approved days/hours or rate changed. Before creating anything, look in the invoice list for an existing invoice for that period; a forgotten saved invoice is not a reason for a second one.

If the client questions the work or price, compare the agreement and confirmation first. Keep the invoice number and exact error. You can correct a draft while it is editable and has not been issued. Do not overwrite an issued invoice’s original amounts or VAT; ask your accountant how to make a correction linked to that invoice. Retry sending only after a confirmed transmission rejection, using the same unchanged original when allowed. If the outcome is uncertain, ask support before retrying. A transport failure alone does not require a credit note.

Keep the invoice, work confirmation, delivery result and original files together. That gives you a simple answer to “What did I bill, was it delivered, and has it been paid?”