PDF for tender documents: what requirements apply?

Why tenders impose strict PDF requirements

In European tenders (e-procurement portals) PDF documents are assessed for completeness, authenticity and tamper-proof properties. An editable PDF without signature or flatten raises doubts about authenticity. Contracting authorities increasingly require PDF/A (archived PDF), signatures or specific file size limits.

Requirements for tender documents

Always check the tender documents themselves for exact requirements. Common requirements: maximum file size (e.g. 10 MB per attachment), PDF format (PDF/A-1b is archived and long-lasting), no password on the file (the portal must be able to open it), signature required (with qualified electronic signature for formal submissions), and a specific file naming convention.

Flatten for tamper-proof PDF

Flatten all form fields and annotations before submitting the document. A flattened document cannot be edited after submission. Use the Flatten tool on PDFrust. This increases the credibility of the document and prevents questions about authenticity.

Adding a signature

A simple electronic signature (image of your signature) is suitable for less formal submissions. For formal European tenders a qualified electronic signature (QES) is mandatory — this requires a certificate from a recognized CSP (such as QuoVadis, DigiCert or Certinomis). Add the signature with the Sign tool on PDFrust.

Compress for portal submission

Tender portals often have strict file size limits (e.g. 10 MB per document, 50 MB total). Compress your documents with the Compress tool before submitting. After compressing, check that quality is still acceptable — especially for attached drawings or photos.

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