Siggy vs Annature: pay per envelope, or pay one price?

Start here: work out which side of the line you are on

Annature charges $1.75 an envelope with no monthly fee. Siggy charges one flat price a month, and the free plan sits underneath it. So there is a crossover, and here it is in one line of arithmetic you can check yourself.

Siggy Starter is $10 a month, which is the price of 5 Annature envelopes. From the 6th envelope in a month a flat plan costs less, and it keeps costing less every month after that — the gap compounds, because our number does not move and theirs does. Siggy Professional, at $15 for 100 envelopes and 5 seats, is the price of 8 envelopes.

Below that line, the answer is not a cheaper subscription — it is no subscription. Our free plan is $0: 5 envelopes a month, 1 user, no credit card, no time limit. If you send a handful of documents a month, start there and pay us nothing until the volume justifies it.

What each one costs at your monthly volume

Annature's column is their published rate multiplied out. Siggy's column is whichever plan covers that volume — envelopes and seats included, same number every month. Both columns are monthly billing; Siggy is 20% cheaper again if you pay annually, and that is not counted below.

One price you can budget, or a bill that moves with tax season

Per-envelope pricing is genuinely fairer in a quiet month. The trade-off is that it has no ceiling. July to October, engagement-letter season, a merger, an ATO deadline — the months when a practice sends the most are the months the invoice is largest, and they are the same months you have least attention to spare for an invoice.

A flat plan does the opposite. Siggy Professional is $15 a month whether you send one envelope or 100. It is a fixed line in the practice budget and it does not move.

The other structural difference is seats. Annature's pricing page states that unlimited users are included; on Siggy, seats come with the plan — 5 on Professional at $15 a month, 15 on Business at $20, and unlimited seats on Unlimited at $100. A practice of one to fifteen people never touches that ceiling, and adding a colleague to a Siggy plan does not add a line to the invoice or take an envelope off anyone else.

What an identity check costs on each platform

Annature charges $9.60 per identity verification, plus $4.30 to add AML and CTF screening — $13.90 for a screened check. Siggy's identity verification starts at $6.00 per completed check, and screening is part of the check rather than an add-on.

On like-for-like screened checks that is about 57% less per check, and about 38% less than Annature's unscreened base check.

One thing to be straight about on our own price: Siggy's per-check rate improves with pack size, so the figure above is the best rate, on the largest pack. The smaller packs cost more per check and every pack rate is published on our pricing page — 5 for $35, 20 for $130, 50 for $300.

What a Siggy check covers, so you can match it against your own AML/CTF program: a government-records identity check, a biometric face match against the photo ID, and screening against politically-exposed-person and global sanctions lists — included in the check, not priced as an extra. Every check is evidenced on the Certificate of Completion with the rest of the audit trail.

Siggy's identity verification is delivered through an accredited Identity Service Provider.

Tranche 2 of the AML/CTF regime took effect on 1 July 2026, and the Tax Practitioners Board has had proof-of-identity expectations for client verification since TPB(PN) 5/2022. If your practice is now verifying clients as routine, the per-check price stops being a rounding error. Fifty checks a year is $695 at $13.90 and $6.00 × 50 at ours.

Links: How to verify a client's identity online in Australia · TPB proof-of-identity requirements · Tranche 2 for accountants

What the price buys

A low price is only worth anything if the record it produces holds up. Here is what sits behind ours, on every plan including the free one.

• The document comes back sealed. Every completed envelope is returned as a PAdES-sealed PDF — tamper-evident, so a later change to the file is detectable rather than arguable.
• The audit trail is hash-chained. Every step of the signing is recorded and each entry is chained to the one before it, so the sequence cannot be quietly edited after the fact. It is issued as a Certificate of Completion, filed alongside the signed document.
• The legal position is stated, not implied. Siggy is built around the conditions in the Electronic Transactions Act 1999 (Cth): an explicit consent step, a method that identifies the signer and indicates their intention, and a record that makes both demonstrable.
• Your data stays here. Siggy is Australian-owned and Australian-hosted, with documents, audit trails and certificates stored in Sydney. Our trust page sets out the detail.
• Two-factor authentication is compulsory, on every Siggy account, not an option a busy practice forgets to turn on. Where a document itself needs a second factor, an access code can be required before it opens, and that step is evidenced on the certificate.
• We handle personal information under the Australian Privacy Principles in the Privacy Act 1988 (Cth), and we run no third-party trackers on this site.

That is the substance underneath $15 a month. The price is a pricing model, not a shortcut.

What both of us already do

Worth saying, because it narrows the decision to the things that actually differ.

Both are Australian. Annature's trust page states that all Annature data is stored with Amazon Web Services in the ap-southeast-2 region in Sydney. Siggy is Australian-owned and Australian-hosted too; our trust page sets out where data sits and what the audit record contains. Both send a tokenised link so your client signs without creating an account. Both return a sealed document with an audit trail. Both offer SMS delivery — Annature at $0.12 per SMS plus $15 a month if you want branded links; Siggy at A$0.50 per envelope that texts its signers — invite plus reminders included.

The thing neither of us is required to have, and which we think matters for Australian practices, is a clear position on the law that makes any of this binding. Electronic signatures are recognised in Australia under the Electronic Transactions Act 1999 (Cth) — section 10 sets the conditions: the method must identify the signer and indicate their intention, be as reliable as appropriate, and the recipient must consent. We have written that up in plain English: are electronic signatures legally binding in Australia?

What breaks if you move

Nothing you would notice. Siggy is deliberately built to work the way DocuSign and Annature work: upload the PDF, drag the fields onto it, add recipients, send. Your client gets a link, signs on a phone or a laptop, and no one creates an account. You get the sealed PDF and a certificate of completion back.

You do not need to migrate anything. Signed documents you already hold stay where they are — they are finished records, not live data. The practical test takes about ten minutes: sign up for the free plan, send one real engagement letter to a client who is expecting it, and see how the signing experience lands with them. If it does not, you have lost ten minutes and no money.

On integrations: Xero and MYOB integrations are in build. Tell us which one matters most to your practice and we will tell you where it sits in the build — send us the name of your system and it goes straight to the people writing it.