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For accountants & professional services

From proposal to paid engagement in one link.

Accounting firms, consultants and agencies send engagement letters and onboarding forms that clients sign and pay in one step, without anyone having to trust a provider with the paperwork.

Start freeWhy it can be trusted

Busy season means hundreds of engagement letters

Sending one at a time doesn't scale.

Client financial data is sensitive

Tax returns, statements and IDs shouldn't be readable by yet another vendor.

Getting paid lags getting signed

The deposit or first invoice follows days later, if it's remembered at all.

What you get

Built for accountants & professional services.

Bulk send and templates

Send the same engagement letter to your whole client list, each with their own details prefilled (bulk send is on Business).

Deposit on signature

Collect the retainer or first payment through your own Stripe account as clients sign (Business plan).

End-to-end encrypted

Documents and attachments are encrypted before they leave the browser, so we can't read client financials.

Attachments and conditional fields

Ask clients to attach documents, show questions only when relevant, and calculate totals automatically.

Firm-wide teams

Invite staff in bulk or let anyone with your company email join automatically. Share envelopes and templates.

Onboarding on your website

Embed a signing widget or share a public link, so new clients start the engagement themselves.

How it works

Four steps, start to sealed.

  1. 1

    Build the letter once

    Fields, fee calculations and the deposit amount, saved as a template.

  2. 2

    Bulk send for the season

    Each client gets their own copy with their details prefilled.

  3. 3

    They sign, attach and pay

    On their phone, in one sitting.

  4. 4

    Track it in reports

    See who has signed, who's waiting, and export it to CSV.

Common documents

What teams like yours send.

  • Engagement letters and proposals
  • Client onboarding and intake forms
  • Authorization and consent forms
  • Statements of work and change orders
  • Independent contractor agreements
  • NDAs
  • Payroll and HR onboarding forms
  • Vendor and subcontractor agreements

For IRS authorization forms, follow the IRS's current rules on electronic signatures and identity verification for each form. SealProof's photo ID check and audit trail can support those checks, but they don't replace your own review of the rules.

Certificate of Completion

Sealed inside the signed PDF

Document2026 Engagement Letter.pdf
Original fingerprintSHA-256 4be1c09f7a2d…d5b0e8a61c3f
SentSep 23, 2026 · 2:02 PM
CompletedSep 23, 2026 · 2:31 PM
1. Jordan Mitchell
Email
jordan.mitchell@example.com
Role
Signer
Signature
Drawn by hand
Viewed
Sep 23, 2026, 2:14:07 PM UTC
Signed
Sep 23, 2026, 2:19:42 PM UTC
IP address
203.0.113.24
Device
Safari on iOS
Authentication
Unique emailed link + one-time code + photo ID and selfie check
Photo ID
Driver's licence (US) and live selfie, verified by Stripe Identity; name on ID matches
Prefilled by sender
4 fields; 1 changed by the signer
Consent
Agreed to sign electronically
Disclosure
Accepted the electronic record and signature disclosure (SHA-256 e03c0105…bccf8602)
Sample. Every certificate is sealed, timestamped and anchored with the document.
Questions

What people ask.

Can clients upload documents while signing?
Yes. Add attachment fields. Files are encrypted in the browser and embedded in the sealed PDF.
Does it work with our existing tools?
The API and webhooks connect SealProof to your practice management system, and Zapier-style hooks cover common automations.
How much does it cost?
See pricing. There are flat plans with no per-envelope fees on Team and Business.
Also built for

Other teams using SealProof.

Insurance agenciesApplications, coverage rejections and policy changes, signed on any phone, with an audit trail built for carrier review.Law firmsEngagement letters and settlements your provider can't read, with evidence that stands up when a signature is challenged.Financial advisors & lendersAccount forms, advisory agreements and loan documents, with the identity checks and controls your compliance team expects.Real estateOffers, disclosures and leases with several parties, signed from phones, with a clear record of who changed what.

Try it with your own documents.

Start free, or send our vendor review packet to whoever approves your tools.

Start freeFor compliance reviewers