For most businesses, picking an e-signature tool is simple. For tax preparers it isn't — because Form 8879 has a requirement ordinary documents don't: when a client signs remotely, the IRS expects the signer's identity to be verified. That single rule rules out a lot of generic e-signature tools, or at least means you need an add-on. Here's how the options actually stack up for a tax practice.
Full disclosure: FinishTax is our product. Every competitor fact below comes from that vendor's own pages, read on September 30, 2026, and linked where it's used; FinishTax's come from our pricing page. We couldn't load TaxDome's site that day, so this guide doesn't describe TaxDome's current e-signature options or prices.
The One Thing That Matters Most: Identity Verification
A plain e-signature — click here to sign — is fine for an engagement letter. For a remote Form 8879, the IRS expects identity verification through an approved method such as knowledge-based authentication (KBA) or document + selfie verification at NIST IAL2. So the real question isn't "can this tool collect a signature?" — it's "does it verify identity in an IRS-accepted way, and what does that cost per return?"
The Options Compared
| Tool | 8879 identity verification | Built for tax? | Cost model |
|---|---|---|---|
| FinishTax | Up to ID + selfie (IAL2), chosen per envelope, no per-check fee | Yes | Per firm, from $29/mo; e-signature on paid plans only (source) |
| SafeSend | KBA, no KBA fees | Yes, intake to delivery | By request; pay-per-return or per-delivery options, no per-seat fees (source) |
| TaxDome | Not checked: we couldn't load TaxDome's site on September 30, 2026 | ||
| DocuSign | ID verification add-on from $2.40 per attempt; KBA not in Standard or Business Pro | General-purpose | Per user; Standard $30/mo on an annual plan, 100 envelopes per user a year (source) |
| Adobe Acrobat Sign | We couldn't find it on Adobe's plan pages | General-purpose | Acrobat plans; no usage caps on e-signatures in teams plans (source) |
FinishTax
FinishTax lets you choose the identity check per envelope, up to government ID + selfie verification at NIST IAL2, built into the signing flow — the client can't open and sign the 8879 until they've verified at the rung you selected. Because it's part of the practice platform, there's no separate per-return signing charge, and the signed document plus the verification audit trail are stored automatically with the client's file.
SafeSend
SafeSend covers the tax engagement from intake through delivery: engagement letters, organizers, document requests, return delivery with 8879 signing, K-1 distribution, invoicing and payments. It assembles returns from tax software including UltraTax CS, GoSystem, Lacerte and CCH Axcess. Signers verify with KBA, which SafeSend reports succeeds 97% of the time, and it doesn't charge KBA fees (SafeSend client experience; SafeSend tax returns). It doesn't publish prices: its pricing page describes pay-per-return or per-delivery options with no per-seat fees and asks you to request pricing (SafeSend pricing). See FinishTax vs SafeSend.
TaxDome
We couldn't load TaxDome's site on September 30, 2026, so we can't confirm its current e-signature or identity-check options here. Our FinishTax vs TaxDome comparison covers its features as of April 2026, and our TaxDome pricing explainer records the prices TaxDome published on August 6, 2026. Check TaxDome's own pages for current details.
DocuSign & Adobe Acrobat Sign
Both are general-purpose e-signature platforms, not built for tax. DocuSign's eSignature Standard plan is $30 per user a month on an annual plan and includes 100 envelopes per user a year. Knowledge-based authentication isn't included in its Personal, Standard or Business Pro plans, and ID verification is an add-on starting at $2.40 per attempt (DocuSign pricing). Adobe says its Acrobat for teams plans have no usage caps on e-signatures; we couldn't find its identity-verification options or their prices on its plan pages (Adobe Acrobat for business). Either way, you'd still be running a separate tool from your client records and workflow, so they make the most sense for firms that already standardize on them company-wide.
How to Choose
- Solo or small firm wanting it all in one place: a tax platform with built-in verified e-signature (like FinishTax) avoids a separate subscription and per-return fees.
- High-volume delivery firm: SafeSend assembles returns from your tax software and delivers them for review, signature and payment.
- Already on a full suite: use its built-in signing rather than adding another tool, and check what each identity check costs: Canopy charges $1.25 per KBA credit, a Karbon KBA request uses two eSignature credits, and Financial Cents sells KBA at $1–$2 each (Canopy; Karbon; Financial Cents).
- Standardized on DocuSign/Adobe firm-wide: budget for the identity-verification add-on and confirm it meets the 8879 requirement.
The Bottom Line
The best e-signature tool for a tax preparer is the one that verifies identity in an IRS-accepted way without bolting on extra cost or a disconnected app. For most solo and small firms, built-in verified signing inside the practice platform is the cleanest answer. FinishTax includes it — a step-up identity ladder chosen per envelope, up to ID + selfie at NIST IAL2, no per-return fee — on every paid plan from $29 a month, with a 7-day trial that takes a card to start and charges nothing until day 8. The free plan doesn't include e-signature.