Electronic signatures for UK small businesses

The customer said yes on the phone. Three days later the signed copy still has not come back, because signing it means finding a printer. This is a guide to closing that gap without creating a worse problem in its place.

Pixacomms Ltd, Cardiff · Updated September 2026

This is written for owner-run UK businesses — trades, agencies, installers, small practices — deciding whether to move signing off paper, and wanting to know what they are actually buying. It covers what the law requires, the three types of electronic signature and when the difference matters, what makes a signed PDF stand up if somebody challenges it, and how to read a supplier’s pricing page without getting caught by the per-user trap.

Each section is a summary with a link to a longer piece, so you can read this in ten minutes and go deep only where it affects you.

Are electronic signatures legal in the UK?

For the vast majority of business documents, yes. Electronic signatures have been admissible in evidence in the UK since the Electronic Communications Act 2000, and in 2019 the Law Commission confirmed that an electronic signature is capable of executing a document wherever a signature is required, provided the person signing intended to authenticate it. A quote, a service agreement, a hire agreement, a purchase order, a supplier contract, an acceptance of terms — these are ordinary business paperwork, and signing them electronically is unremarkable.

The exceptions are narrow but real. Deeds, wills, and certain land and property formalities carry extra requirements — witnessing in particular is not something a tick box makes go away. If a document in your business might fall into one of those categories, have it checked by whoever handles your legal work rather than by a software supplier, ours included.

The more useful question is not whether it is legal but what you could prove if it were disputed. Legality is the easy half; evidence is the half that settles arguments. That is written up in full in is an electronic signature legally binding in the UK?, including what a court is actually looking for and why a typed name at the bottom of an email sometimes counts.

Simple, advanced and qualified signatures

UK law recognises three tiers. A simple electronic signature is a mark made with intent to sign — a drawn squiggle, a typed name, a tick in a box. An advanced electronic signature is uniquely linked to the signer, capable of identifying them, and tied to the document in a way that reveals any later change. A qualified electronic signature is an advanced signature made with a certificate from a qualified trust service provider on secure hardware.

Almost no small business in the UK needs a qualified signature. The tiers are not a quality ladder to be climbed; they are a legal distinction that matters in a handful of regulated and cross-border cases. What most businesses actually need is the middle ground: a signature bound to the file, so that a change made after signing is detectable rather than deniable. The comparison of simple, advanced and qualified signatures explains where the boundaries sit and which tier a given document really calls for.

What makes a signed PDF actually hold up

Here is the distinction that costs people money. A picture of a signature pasted onto a PDF is a picture. Anyone can move it, anyone can edit the page around it, and nothing in the file records that it happened. A cryptographic signature takes a SHA-256 fingerprint of the document and signs that fingerprint, so changing a single character afterwards breaks the seal and ordinary PDF software will say so.

The standard for doing that inside a PDF is PAdES, set out in ETSI EN 319 142. Every document sealed by Pixasign is PAdES B-T: an RSA-3072 signature using SHA-256, plus an RFC 3161 timestamp. The timestamp is the part worth understanding, because a time you assert about your own document is worth very little. Ours are issued by DigiCert — an independent, publicly trusted timestamping authority — so the attestation of when that signature existed does not come from us, and anyone can check it. What is PAdES, and why does it matter? goes through the levels and what each one buys you.

What to look for when you choose a tool

Most of the buying mistakes in this category happen on the pricing page rather than the feature list. Four questions decide whether a tool fits a small business.

That last row is the one people discover too late. Evidence that only works while you keep paying a supplier is not evidence you control. If the signed PDFs and their audit trails cannot be downloaded and checked by somebody who has never heard of your supplier, you have rented your paperwork rather than owned it. Our roundup of the best DocuSign alternatives in the UK scores the main options on those four questions rather than on feature counts.

DocuSign is the default choice for good reasons: it is mature, everyone recognises the name, and it does far more than most small businesses will ever use. That last part is also the catch, because the per-seat model and the enterprise feature set are built for companies with a procurement department. If you want the direct comparison, including the places where DocuSign is genuinely ahead of us, read Pixasign compared with DocuSign.

The same problem, four different trades

Nobody buys “signatures”. They buy a fix for one specific document that keeps getting stuck. These pages are written around the documents rather than around the software.

Construction and principal contractors

Nobody asks whether you had RAMS. They ask whether you can show that a named operative accepted a particular version before they picked up a tool. That is a version-control problem and a timing problem, and a photographed sheet answers neither half. Digital RAMS and subcontractor sign-off covers the round trip and what you are left holding eighteen months later.

Tradespeople and builders

The money problem in a trade business is rarely the original quote. It is the variation: the extra socket, the second coat, the wall that turned out to be wet — all agreed verbally in a hallway, all disputed at invoice time. E-signatures for tradespeople and builders is about getting quotes and variations accepted in writing without killing the pace of the job.

Security, access control and AV installers

Installers carry a heavier paperwork load than the job value suggests: handover certificates, commissioning records, maintenance agreements, and sign-off from a facilities manager who is never on site at the same time as the engineer. E-signatures for security, access control and AV installers deals with handover and recurring-contract paperwork.

Letting and estate agents

Lettings is the hardest shape of the lot: several tenants, sometimes a guarantor, and a landlord who may be in another country, all signing one agreement against a move-in date that will not move. E-signatures for letting and estate agents covers multi-signer documents, signing order, and holding an audit trail together when everybody involved is mid-move.

How Pixasign fits

We are a UK product built by a small UK company, and the shape follows from that. Flat monthly pricing with unlimited users: £29 a month for 50 documents, £59 for 200, £99 for 500, VAT included, so the number on the page is the number that leaves your account. Your customers never pay and never register — they tap a link, sign on a phone, and that is the end of their involvement. Everything is hosted in Nuremberg with backups in Reykjavík; nothing sits in the United States.

Every signed document comes back sealed to PAdES B-T with a DigiCert timestamp, alongside an evidence certificate: who signed, the address it went to, their IP and approximate location, the device, and the full timeline to the second, with SHA-256 fingerprints of the file before and after sealing. The events are hash-chained, so each one locks in the one before it. Anyone can test a finished document on our free public checker without an account.

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