A professional PDF invoice needs your company branding, payment details, and your signature — and it should be protected against editing by the recipient. Here is how to create, customize, and secure a PDF invoice for free.
If you have an existing invoice in Word, Google Docs, or Excel — print it to PDF first. On any OS, File → Print → Save as PDF creates a clean invoice PDF. Alternatively, download a free invoice PDF template from any accounting website.
Open the invoice PDF in pdfeditor.onl/pdf-studio. Use the Add Text tool to fill in: client name and address, invoice number, date, line item descriptions, amounts, totals, and payment terms.
Tip: Use Helvetica 10pt for data entry to match standard invoice typefaces. Add each field as a separate text box for precise positioning on the invoice lines.
Go to pdfeditor.onl/add-image-pdf. Upload the invoice PDF and add your company logo PNG to the top of the first page. Position it in the header area.
Use pdfeditor.onl/sign-pdf to add your drawn or typed signature to the signature line. Date it with the Add Text tool.
Use pdfeditor.onl/protect-pdf to set permissions that prevent the recipient from modifying the invoice amounts or details. Allow printing but restrict editing.
In most jurisdictions, a PDF invoice is legally valid with or without a signature, as long as it includes the required commercial information (your business details, VAT/tax number if applicable, and itemized amounts). Check local invoicing laws for your jurisdiction.
Use the Add Text tool to type the invoice number manually each time. For automated sequential numbering across many invoices, use dedicated invoicing software.