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Accounting Guide · OEC 2026

Electronic signature for accountants: complete guide

Article 151 of the OEC Code of Ethics requires a written engagement letter prior to any service. Combined with the requirements of the Commercial Code (certifications art. L823-12-1, board meeting minutes art. L232-1) and the Labour Code (payslip L3243-2), this represents a significant volume of contractual documents that an accounting firm must manage. This guide explains how to dematerialize all of them with enforceable legal value.

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Legal framework: electronic signature in accounting practice

The accountant is subject to strict professional rules (OEC Code of Professional Conduct) which impose precise contractual formalism. Advanced electronic signature (AES) compliant with eIDAS satisfies these requirements while simplifying the client relationship.

  • Engagement letter: AES recommended (art. 151 OEC Code of Professional Conduct) — proof of prior acceptance
  • Bank/URSSAF certificates: AES + verification URL (art. L823-12-1 C. com.)
  • General meeting minutes approving accounts: multi-signatory AES (art. L232-1 C. com.)
  • Dematerialized payslip: employer AES + employee secure archive over 50 years (art. L3243-2 C. trav.)

Documents electronically signable in accounting practice

Engagement letter (OEC art. 151)
Accountant certificate (bank, URSSAF, landlord)
General meeting minutes approving accounts (art. L232-1)
Dematerialized payslip (Macron law art. L3243-2)
Social and tax management mandate (DSN, VAT, IS)
Service agreement and confidentiality undertaking

Typical workflow for an accounting practice

  1. 1

    Prepare the engagement letter

    Template compliant with art. 151 OEC: scope, fees, duration, termination conditions. Word or PDF download supported.

  2. 2

    Invite the client to sign

    Secure link sent by email with SMS OTP. The client signs from their phone in 2 minutes — no in-person meeting required.

  3. 3

    Launch the engagement immediately

    Qualified timestamping proves prior acceptance. No risk of fee dispute in case of litigation.

  4. 4

    Archive automatically for 10 years

    The signed letter + audit trail are archived in compliance with art. L123-22 of the Commercial Code. Accessible in one click for any inspection or dispute.

Frequently asked questions — Electronic signature in accounting practice

Is the engagement letter really mandatory?
Yes — article 151 of the OEC Code of Professional Conduct requires every accountant to conclude a written engagement letter BEFORE the service begins. Absence or failure to sign exposes to disciplinary sanctions (reprimand, suspension) and complicates any fee dispute.
Is an electronically signed certificate accepted by banks?
Yes, without reservation. Major French banks accept certificates signed with AES eIDAS level — which has become the standard since 2024. The verification URL printed on the PDF allows the account manager to verify authenticity in one click.
Is the dematerialized payslip mandatory?
No, but optional for the employer. Since the Macron law (2017), the employer can switch to electronic payslips without prior employee agreement — it is sufficient to inform them one month in advance. The employee may object at any time.
What level of signature for general meeting minutes?
Advanced signature (AES) recommended. It provides a presumption of reliability (art. 1367 Civil Code) and meets evidential requirements in case of resolution challenge. Compatible with a dematerialized minutes register (PACTE law).
How long must signed accounting documents be kept?
Minimum 10 years (art. L123-22 Commercial Code). Certyneo automatically archives each document + its eIDAS audit trail for this duration, accessible from your dashboard.
→ Complete electronic signature guide · → Certyneo solution for accountants · → eIDAS guide — SES/AES/QES levels

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