Guide · Accountants
Engagement letter template: is e-signature valid?
Every accounting engagement starts with a letter defining scope, fees and responsibilities. Most firms still email a PDF and wait for a scanned signature. This guide gives you a usable structure for that letter, then answers the question firms actually ask: if a client later disputes it, does an electronic signature hold up in court the same way a wet one does.
- A clear structure: scope, fees, responsibilities, sign-off
- eIDAS Article 25: an e-signature cannot be denied legal effect just because it is electronic
- A qualified signature adds weight, but is not required for most engagement letters
What must an accounting engagement letter actually contain?
An engagement letter should state the scope of services in specific terms: which returns, filings or advisory work are included, and what is out of scope. Add the fee basis, whether that is fixed, hourly or retainer, and how out-of-scope work gets billed. Set out each party's responsibilities: what the client must provide and by when, and what the firm delivers and by when. Cover confidentiality, how long records are kept, how either side can end the engagement, and a short limitation-of-liability clause reviewed by your own insurer or professional body. A one-page summary at the top, in plain language, helps a client actually read it before signing, rather than skipping to the signature line.
Can a client validly sign an engagement letter electronically?
Yes. An engagement letter is a private contract between your firm and a client, not an act that EU or national law reserves for a notary, so there is no general requirement for a handwritten signature. What matters is that the signature method can show who signed, when, and that the signer intended to be bound. A basic click-to-sign captured with a timestamp and an audit trail already meets that bar for most engagement letters. The exception is any territory or matter type where a professional body or a specific national rule requires a higher signature level or a notarised act, which is unusual for an ordinary engagement letter but worth checking once with your own supervisory body.
What does eIDAS actually say about this (Article 25, in plain terms)?
Article 25(1) of the eIDAS Regulation (EU) 910/2014 says an electronic signature cannot be denied legal effect or admissibility as evidence in legal proceedings for the sole reason that it is electronic, or that it does not meet the requirements of a qualified electronic signature. In plain terms, a simple or advanced electronic signature is not automatically weaker in court just because it is not the highest tier. Article 25(2) then gives a qualified electronic signature the same legal effect as a handwritten signature, and Article 25(3) says a qualified signature issued in one member state is recognised as one in every other member state. Most engagement letters do not need that top tier to be enforceable.
Does a simple e-signature hold up as well as a scanned wet signature?
In practice, an electronic signature captured properly can be easier to defend than a scanned wet signature, not harder. A scanned signature only proves someone once held a pen; it carries no record of when it was applied to this specific document or by whom. An electronic signature process that logs the signer's identity method, the device and browser used, the exact timestamp, and the version of the document shown at signing gives you a paper trail a scanned image cannot. If a client later claims they never agreed to the letter, that record is what your firm produces, not a memory of a phone call.
When would a firm want a stronger (qualified) signature instead?
A qualified electronic signature is the only e-signature type eIDAS treats as automatically equivalent to a handwritten one, and it needs a qualified certificate issued by a trust service provider, usually tied to a specific identity check. Most accounting engagement letters do not need that: an advanced electronic signature with a clear audit trail is enough for a private services contract. Reach for a qualified signature instead for specific documents where a client's own bank, court or counterparty demands it, or where national law names it directly for a particular act. Braigest applies an advanced electronic signature with a PAdES seal, not a qualified one, so check separately if a specific document in your pack needs that higher tier.
How Braigest seals the signed engagement letter with an evidence page
Once every party has signed, Braigest applies one PAdES seal across the finished document and attaches an evidence page: the time of consent, the device and identification method used, any reviewer decisions along the way, and the full audit history of the document. The engagement letter can sit in the same signed pack as the rest of the onboarding, the ID check, the risk questionnaire, the fee schedule, so the client signs once for the whole set rather than juggling separate tools for each document. The sealed file is what you keep on record if the engagement is ever questioned later.
In Braigest
One PAdES seal for the whole engagement pack
Braigest's native e-signature applies one PAdES seal and evidence page across the engagement letter and every other document in the same run. It is included from the Solo plan at €29/month.
Frequently asked questions
Does an e-signed engagement letter need to be notarised?
No. An engagement letter is a private services contract, not an act reserved for a notary under EU or most national law. An electronic signature with a clear audit trail is normally enough.
What happens if a client denies signing the letter?
The evidence page shows the exact time of consent, the device and identification method used, and the version of the document presented at signing, which is the record your firm relies on if a client disputes it.
Is a qualified electronic signature the same as what Braigest provides?
No. Braigest applies an advanced electronic signature with a PAdES seal, not a qualified electronic signature. Most engagement letters do not require a qualified signature; check separately if a specific document in your pack does.
Can the engagement letter and the rest of the onboarding pack be signed together?
Yes. Documents in the same run share one seal at completion, so the client signs once for the engagement letter, the fee schedule and any other document in the pack.
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