Attest vs SignNow

Attest and SignNow at a glance

SignNow is the e-signature product of airSlate, based in Brookline, Massachusetts, with self-serve plans from Business to Enterprise and site licenses for larger organizations. Attest is built around a different promise: proof anyone can check, on documents only the parties can read. SignNow's prices are as published in its pricing app on October 12, 2026; its other details are as published on its own pages on October 11, 2026.

	Attest	SignNow (as published October 12, 2026)
Who can read your documents	Only you and the people you send them to. Every document is end-to-end encrypted in your browser	"AES-256 bit encryption for storage and data at rest" and TLS 1.2/1.3 in transit. No end-to-end encryption described
How a signer signs	Approves with a passkey only they control (Face ID, Touch ID, Windows Hello or the device PIN)	Opens an emailed invite, with or without a SignNow account; password, SMS or phone-call checks on select plans
What ties the signature to the document	Each signer's own cryptographic signature over the document's fingerprint and their entries	"a trusted digital certificate issued by airSlate" on every signed document
Checking a signed document	Anyone, free, with the open-source verifier inside every signed copy	The airSlate certificate details, in Adobe Acrobat or Adobe Reader
How usage is counted	Documents sent: 20 a month on Signing. A document voided before anyone signs is given back	Signature invites: 100 per user a year on annual plans, 10 a month on monthly plans. A cancelled invite still counts
Prove a fact without the document	Yes: a zero-knowledge proof that you signed, and the date it was completed	Not offered
Free	2 documents, in total	7-day trial
Entry paid plan	Signing: $5 a month for 20 documents	Business: $20 a month, or $96 a year ($8 a month)

What 20 documents a month really cost

SignNow's headline price is low, and for a few signature invites a month it is a fair deal. Its Business plan includes "an annual allowance of 100 signature invites per user or a monthly allowance of 10 signature invites per user"; unused invites don't roll over, and extra invites are billed as you go, at $0.96 each on Business, as published on October 12, 2026. SignNow's pricing app also tests other prices, so some visitors see different figures.

Sending 20 documents a month, at one invite each	Attest	SignNow Business (as published October 12, 2026)
Plan	$5 a month	$96 a year, or $20 a month
Included	20 documents a month	100 invites a year, or 10 a month
Extra usage	None at this volume	140 invites a year at $0.96 ($134.40), or 10 a month ($9.60)
Total	$60 a year	About $230 a year on annual billing, or $29.60 a month on monthly billing

The SignNow totals are computed from its published prices. SignNow counts one invite however many signers or documents it carries, and Attest counts each document once, however many signers it has (up to 20). The difference is the allowance: Attest's 20 a month is a flat $5, and a document voided before anyone signs is given back, while SignNow bills each invite beyond the plan's allowance, and a cancelled invite still counts. Attest's plans are month to month, with no annual commitment, and you can cancel any time.

Privacy: who can read your contracts

SignNow's security page says "All data is encrypted using TLS 1.2/1.3 to protect data in transfer and AES-256 bit encryption for storage and data at rest." That protects stored files and connections. SignNow describes no end-to-end encryption, so its service can decrypt the documents it stores.

Attest encrypts every document in your browser before upload, with AES-256-GCM, and locks the key separately to each person you send it to; what signers type into the document is encrypted in their browser too. Attest stores your document only as ciphertext it can't read. We compared 21 e-signature services in October 2026, Attest and 20 others, and Attest was the only one that end-to-end encrypts every document, for every signer, by default.

How signers sign

"Whether or not you have a SignNow account, you can sign any document sent to you via a signature request." Invites go by email, or by SMS in listed countries, and on select plans the sender can require a password, a text message or a phone call. Those checks work for single invites, not bulk invites or invite links.

On Attest, every signer approves with a passkey: a cryptographic key only the signer controls, unlocked with Face ID, Touch ID, Windows Hello or the device PIN. The passkey signs a statement naming the exact document, by its fingerprint, and everything the signer entered, so the signature belongs to that signer and that document. There is no account or password to create, and setting up takes one prompt with most passkey providers.

Proof after a plan ends

SignNow says that when a plan expires the account becomes read-only, with "no time limit": signed documents, history and audit trails can still be viewed and downloaded. If you delete the account, "Your documents, templates, and personal data stored in SignNow are permanently removed in line with our retention policies." A downloaded SignNow PDF carries airSlate's certificate, which Adobe Acrobat and Adobe Reader can show.

An Attest signed copy needs neither an account nor Attest. Every party downloads the same sealed PDF: the signed pages, with a "Signed with Attest" stamp on each signature and a seal line at the foot of every page, a certificate of completion, the audit trail up to completion and a "Verify it yourself, without us" page, with the full evidence, the original document and a standalone verifier attached inside. Drop it on that verifier in any browser and it checks the original document against what every signer signed, each signer's passkey signature and entries, Attest's anchored record of the agreement on the Horizen public blockchain, and that nothing was added to the PDF after it was sealed; it also re-makes every page you see from what was signed and compares the result byte for byte. A film on the signing page shows it on a real agreement with Attest blocked: the copy still verified, reading only a public blockchain node, and changing the pages made it fail.

Proving an agreement without sharing it

With Share proof, a signer creates a zero-knowledge proof that they, or they and a named co-signer, signed an agreement, and the date it was completed. The recipient sees the email addresses, the completion date, and that the proof is valid and where its record is anchored, never the document, its title or its terms. Each proof is verified on zkVerify. SignNow does not offer this.

When SignNow is the better fit

• Templates and bulk sending. Business includes unlimited templates and fillable fields; Business Premium ($15 a month billed annually, as published on October 12, 2026) adds bulk sending and signing links.
• Integrations. SignNow lists integrations such as Salesforce, Google Workspace and NetSuite, and a developer API with paid plans from $1,000 a year, as published on October 11, 2026.
• Regulated workflows. 21 CFR Part 11 configurations and qualified electronic signatures through eID Easy are available on Corporate (site license) plans.

Who should choose Attest

• Professionals and small businesses whose contracts should stay readable only by the parties: every Attest document is end-to-end encrypted in the browser.
• Senders who want a flat price: 20 documents a month for $5, with no per-invite overage and no annual commitment.
• Anyone who wants proof that verifies without the vendor, in a file that carries its own evidence and verifier.
• People who receive signed documents and want to check them free, with no account.

Starting on Attest

Sign in with your email and set up your signing key with a passkey and a recovery phrase. Upload a PDF of up to 8 MB, add your signers, place their fields and send. Your first 2 documents are free, in total, and signing a document someone sends you is always free.