---
id: KB-GL-004
url: https://app.codecontract.io/help/glossary/what-is-a-qualified-signature
idioma: en
categoria: glosario
subcategoria: firma
audiencia: usuario
nivel: intermedio
actualizado: 2026-08-13
tambienEn: [es]
relacionados: [KB-GL-003, KB-CO-009]
citadoPor: [KB-GL-003]
---

# What is a qualified signature

_The highest level of electronic signature, and when it is genuinely required._

**Responde a:** what is a qualified signature · difference between simple advanced and qualified signature · when is a qualified signature required · qualified signature certificate

**Qualified electronic signature** — One made with a certificate issued by a qualified provider and a secure signature creation device. In the European framework it is the only one legally equivalent to a handwritten signature.

## The three levels

| Level | What it requires | Used for |
| --- | --- | --- |
| Simple | Little beyond acceptance | Internal approvals, acknowledgements |
| Advanced | Identifying the signer and detecting changes to the document | Most commercial contracts |
| Qualified | A qualified certificate and secure device | Whatever the law expressly requires |

Most day-to-day work is handled by a well-executed advanced signature. Qualified adds real friction — the signer needs their certificate — and only pays off when it is required.

> [!IMPORTANT]
> If a specific document requires a qualified signature, the rule governing it says so, not the platform. Ask your adviser before deciding on your own judgement: getting this wrong invalidates the whole document.

> [!WARNING]
> Raising the level "just in case" has a cost: every signer without a certificate is locked out, and the document goes unsigned.

**Do I need qualified for a supplier contract?**

Usually not. Advanced is the norm.

**Does a national eID work?**

It is a qualified certificate, yes, if the signer can use it.

**What about outside the EU?**

Qualified is a European concept. Other countries have their own schemes.

## Ejemplos

**A company wants qualified signatures on every contract.**

- Checks which documents genuinely require it
- Keeps qualified only for those

→ The rest are signed same-day instead of waiting for every supplier to obtain a certificate.

**A client demands a qualified signature and the supplier has no certificate.**

- Checks whether that document really requires one

→ The requirement applies where it is needed rather than by habit.

**A process stalls because three signers cannot obtain their certificate.**

- Separates the documents that require it from those that do not

→ What can move, moves, while the rest is sorted out.

**Nobody knows what it adds over an ordinary signature.**

- Compares what proof each level leaves

→ The decision rests on the real difference rather than the name.

**A document is signed with a certificate and the resulting file cannot be validated.**

- Keeps the document exactly as it was signed

→ Later validation works because nothing has been saved over it.

**A foreign signer holds a certificate from another country.**

- Checks with the adviser whether it serves that use

→ The question is settled before the document goes out.