WooCommerce B2B Service Invoices: VAT, PO Numbers, and PDF Workflow

Why service orders expose invoice gaps

Product stores usually invoice after a paid checkout. B2B service stores are messier: a buyer may need a PO number, finance approval, a proforma, bank-transfer instructions, a separate invoice email, or a credit note when scope changes.

→A business customer needs a VAT invoice before finance will approve payment

→The buyer sends a PO number after checkout because there was no field for it

→Bank-transfer orders need a proforma first and a final invoice after payment

→Partial service refunds need credit notes instead of edited historical invoices

→The accountant needs invoice numbers, VAT treatment, paid dates, and PDF links in one export

The WooCommerce B2B service invoice workflow

1. Capture business billing data before payment

Add company name, VAT/BTW number, invoice email, PO/reference, and cost-centre fields to checkout so the first invoice is usable.

2. Issue a proforma for bank transfer or approval flows

Service buyers often need an internal approval document before money moves. Keep the proforma separate from the final tax invoice.

3. Convert paid orders into final VAT invoices

When the order is paid, create a sequential invoice number, PDF, email attachment, and customer download record tied to the WooCommerce order.

4. Preserve corrections and refunds

Use credit notes for refunds or corrections so the original invoice remains auditable and the accountant can match the adjustment.

Fields a service invoice plugin should support

Field	Why it matters
Company name	Required for B2B invoice identity and customer downloads
VAT/BTW number	Needed for EU B2B VAT evidence and reverse-charge decisions
PO/reference	Helps the buyer's finance team approve and reconcile the invoice
Invoice email	Routes the PDF to accounts payable instead of the order contact only
Payment terms	Supports Net 14/30, bank transfer, and overdue reminder workflows
Credit-note reason	Explains refunds, service changes, or invoice corrections later

Qualification score for B2B service stores

Score 3+ points and the store has a real invoice workflow problem worth a paid early-access conversation.

You sell services, coaching, consulting, retainers, or implementation packages+2

Customers ask for PO numbers or invoices before they pay+2

Bank transfer / invoice-me payment is offered+2

Your accountant asks for invoice PDFs and paid dates every month+1

Refunds require manual credit notes or edited PDFs+2

Early-access offer: €49 B2B service invoice workflow review

Send the store URL, service type, payment methods, PO/reference needs, VAT fields, proforma requirements, and credit-note use cases. The reply can map the current WooCommerce setup to the Lattice Invoices early-access workflow.

Send my B2B invoice workflow

FAQ

Can WooCommerce sell services and still need invoice automation?

Yes. Service orders often create more invoice support than product orders because buyers need PO references, invoice emails, approval documents, payment terms, and sometimes partial refunds or credit notes.

Should a proforma use the same number as the final invoice?

Usually no. A proforma or payment request should not pollute the final invoice-number sequence. The final invoice should be issued when the paid/taxable invoice event occurs.

Where does Lattice Invoices fit?

Lattice Invoices is positioned as the focused WooCommerce EU invoice workflow for VAT fields, invoice PDFs, credit notes, customer downloads, and accountant handoff. This page qualifies B2B service stores for the €49 early-access path.