Wet signature vs e-signature: what's the difference?

This guide explains what a wet signature is, when it is still legally required in Australia, and how e-signature fits into a modern contract lifecycle management workflow.

What is a wet signature?

A wet signature is a handwritten signature applied to a physical document using pen and ink. The term comes from the time when ink required drying before documents could be handled or stored.

Wet signatures have been the standard method of executing legal agreements for centuries. They signal a person's intent to be bound by the terms of a document and have historically been accepted as proof of identity and consent.

In practice, obtaining a wet signature typically involves:

•       Printing the document

•       Physically signing it

•       Posting, couriering, or hand-delivering it to the counterparty

•       Waiting for the counterparty to sign and return it

•       Scanning and storing the executed copy

Each step introduces delay. When multiple parties are involved, or signatories are in different locations, the process can take days or weeks.

What is an e-signature?

An e-signature, or electronic signature, is a digital method of indicating agreement to a document. It does not require pen or paper. E-signatures can take a number of forms, including a typed name, a drawn signature on a touchscreen, or a click-to-sign action within a platform.

Under Australian law, e-signatures carry the same legal weight as wet signatures for the vast majority of commercial documents. The Electronic Transactions Act 1999 (Cth) and equivalent state legislation establish that a contract is not invalid simply because it was signed electronically, provided certain conditions are met:

•       The method of signing identifies the signatory

•       The method indicates the person's approval of the document

•       The method is reliable in the circumstances

•       The other party consents to receiving an electronically executed document

When is a wet signature still required?

E-signatures are valid for most commercial contracts, including NDAs, service agreements, employment contracts, and procurement documents. However, certain document types in Australia still require a wet signature by law:

•       Deeds and instruments that must be executed under seal

•       Wills and testamentary documents

•       Powers of attorney (in some jurisdictions)

•       Statutory declarations

•       Land transfer documents in some states

Requirements vary by state and document type. If you are unsure whether a wet signature is required for a specific document, seek legal advice before proceeding with an electronic execution.

Wet signature vs e-signature: a direct comparison

Both methods are legally valid for most contracts. The differences are practical.

Speed

Wet signatures introduce lag at every step: printing, delivery, signing, return, and storage. E-signatures can be completed in minutes from any device. For high-volume contract environments, that difference compounds quickly.

Cost

Wet signatures carry hard costs including paper, ink, printing, and courier or postage fees. They also create soft costs from delayed contract execution. Deals that sit unsigned are deals at risk. E-signatures eliminate physical costs and reduce the time-to-execution window significantly.

Security and audit trail

Wet signatures are difficult to authenticate after the fact. Verifying whether a signature is genuine typically involves handwriting analysis or witness testimony.

E-signatures captured through a purpose-built platform generate a timestamped audit trail that records who signed, when, and from which device. Plexus captures this evidence automatically as part of the contract management workflow, without requiring any additional steps.

Counterparty experience

Asking a counterparty to print, sign, scan, and return a document adds friction on their side. E-signature removes that barrier. Signatories receive a link, review the document, and sign in one step. Completion rates are higher and turnaround times are shorter.

Storage and retrieval

Executed paper contracts require physical filing or manual scanning and digital storage. E-signed contracts can be stored automatically in a centralised system, searchable and accessible without manual intervention. See how Plexus handles contract storage and search as part of the full contract lifecycle.

How e-signature fits into the contract lifecycle

Signature is one step in a broader contract lifecycle. In many organisations, the signing step is where an otherwise efficient process stalls. Contracts have been drafted, negotiated, and approved, then sit in an inbox waiting for a wet signature.

Integrating e-signature into a contract management platform removes that bottleneck. Contracts move from approval to execution within the same workflow, without breaking momentum or requiring manual handoffs.

With Plexus, the signing step is built into the contract workflow. Once a contract is approved, authorised parties receive a notification to sign. Signatures are captured, verified, and stored automatically, and the executed document is available immediately in the platform. You can read more about how this works in our guide to getting contracts approved and signed faster.

That means no printing, no scanning, no chasing counterparties by email, and no contracts lost in inboxes.