For most small tax and bookkeeping firms we recommend TaxDome: its client portal, unlimited e signatures, invoicing and ready made workflows come in every plan, with IRS style KBA identity checks at $1 per attempt. Seats start at $800 a year for a solo preparer and $1,000 a year per seat for teams. Firms that live in email and do mostly monthly bookkeeping should look at Karbon, the lowest per user price here at $59 a month billed yearly.
Practice management platforms with client portals, e signatures, workflow automation and billing are mature tools that thousands of firms run on today; the newer AI features are still being added.TaxDome: our pick
Best for tax and bookkeeping firms that want clients to upload, sign and pay in one portal.
TaxDome's strength is the client side. Every plan, starting with Essentials, includes a web portal and mobile app for clients, unlimited document storage and e signatures, proposals with payment collection, and ready made automations for tax, bookkeeping and accounting workflows TaxDome plans ↗. The feature table also lists time tracking, invoices built from time entries and recurring invoices TaxDome pricing ↗. TaxDome says more than 15,000 firms use it TaxDome pricing ↗.
For tax preparers, the e signature setup matters. TaxDome lets you request signatures with knowledge based authentication, which it describes as keeping you IRS compliant TaxDome pricing ↗. KBA costs $1 per signer attempt in the US, charged whether the attempt succeeds or not, so a married couple signing costs $2 TaxDome KBA ↗. Clients get two attempts per request TaxDome KBA ↗.
Seats are billed upfront by the year. Essentials is $800 a seat and is the only plan that allows a single team member, Pro is $1,000 and Business is $1,200, with two and three year terms saving up to 12.5 percent TaxDome plans ↗. Pro also sells a monthly seat at $100, and Business offers a four month seasonal seat for $500, useful for tax season help TaxDome plans ↗. On Capterra it averages 4.7 out of 5 from 3,626 reviews, and a learning curve is the most common complaint in the reviews we read Capterra, TaxDome ↗.
Why we like TaxDome
- Portal, e signatures, invoicing and workflow in every plan
- Unlimited e signatures; KBA at $1 per attempt
- Seasonal seats for tax season
- 4.7 out of 5 on Capterra
Where TaxDome falls short
- Billed upfront by the year
- No free trial listed
- Reviewers mention a learning curve
Karbon: best for bookkeeping firms
Best for bookkeeping and advisory firms whose work runs through email and monthly checklists.
Karbon is built around the team's inbox and recurring work. Every plan includes a client portal, time tracking, invoicing with recurring billing and payments, and Team adds work scheduling, notifications and to do lists Karbon pricing ↗. Business adds task automation, tasklist automators and automatic client reminders, which is what most firms want for monthly closes Karbon pricing ↗.
Its AI is the most practical we found and currently costs nothing extra. Karbon AI drafts and refines emails, writes quick replies, summarizes email threads and work conversations, and builds a client summary Karbon AI ↗. Karbon says it does not use your firm's data to train AI models, and admins can turn AI off Karbon AI ↗.
Team is $59 per user a month billed yearly and Business is $89; monthly billing at $79 or $99 needs at least four users Karbon pricing ↗. E signatures are not in the plan price: credits come in bundles from $100 for 100 up to $2,000 for 4,000, and they expire after 12 months Karbon pricing ↗ Karbon e signatures ↗. KBA is available for IRS compliant signatures, but the page does not say what it costs Karbon e signatures ↗.
Why we like Karbon
- Lowest per user price here
- AI email and summaries included for now
- Client portal and payments on every plan
- Admins can switch AI off
Where Karbon falls short
- E signatures cost extra and credits expire
- Monthly billing needs four or more users
- Automation is on the Business plan
Canopy: best for tax resolution
Best for tax firms that also handle IRS notices and resolution work.
Canopy says every plan includes its complete practice management suite: CRM, document management with e signatures, a client portal with secure messaging, recurring task workflows, and invoicing and payments Canopy pricing ↗. Its Tax Resolution add on, at $50 per user a month billed yearly, is the reason to choose it over the others Canopy pricing ↗.
Standard costs $74 per user a month billed yearly, Plus $109 and Premium $149, and annual billing saves 20 percent over monthly Canopy pricing ↗. An AI Notetaker is included at 8 hours per user a month on Standard, rising to 16 on Premium Canopy pricing ↗. KBA for e signatures costs $1.25 per credit on every plan, and ACH payments cost 1 percent capped at $10 Canopy pricing ↗.
Canopy averages 4.6 out of 5 from 851 reviews on G2, where users praise the document handling and automated workflows and complain about time consuming workflow setup and buggy task statuses G2, Canopy ↗. A trial of the full platform is available, but you set it up through a sales demo Canopy pricing ↗.
Why we like Canopy
- Tax resolution add on
- Full suite on every plan
- AI notetaker hours included
- Low ACH fee cap
Where Canopy falls short
- Highest entry price per user
- KBA and tax tools cost extra
- Trial only through a sales demo
Compare them
| Tool | Starting price | Client portal | E signatures | KBA cost | Workflow automation | Billing and payments | Best for |
|---|---|---|---|---|---|---|---|
| TaxDomeOur pick | $800/yr solo; $1,000/yr per seat (Pro) | Yes, web and mobile | Unlimited, included | $1 per attempt | Ready made automations on all plans | Invoices, recurring billing, payments | Tax and bookkeeping firms |
| KarbonBest for bookkeeping firms | $59/user/mo billed yearly | Yes | Credit bundles from $100 | Not published | Task automation on Business | Invoices, recurring billing, payments | Bookkeeping and advisory firms |
| CanopyBest for tax resolution | $74/user/mo billed yearly | Yes, with secure messaging | Included | $1.25 per credit | Recurring workflows; advanced on Premium | Invoices and payments | Tax resolution work |
| QuickBooks Online | Free sign up (QuickBooks Online Accountant) | Client requests in My Accountant tab | Not mentioned | Not mentioned | Projects, tasks and recurring projects | Not in the Work tab | Solo bookkeepers on QuickBooks |
Prices and features from each vendor’s site, checked Oct 9, 2026. Prices change often.
Who this is for
This guide is for small accounting, bookkeeping and tax firms, roughly 1 to 15 people, that run client work out of email, spreadsheets and a shared drive and want one system for clients, deadlines, documents, signatures and invoices.
It answers a different question from our guide to AI tools for accountants. That guide ranks tools by how much AI time saving you get, across research, bookkeeping automation and email. This one is about the platform the whole firm runs on, so we judged on the client portal, e signatures that meet IRS rules, workflow automation, billing and the price per seat. AI is a tiebreaker here, not the main criterion.
If you are a solo bookkeeper with a handful of clients, the free practice tools in QuickBooks Online Accountant may be enough to start QuickBooks Online Accountant ↗ QuickBooks Work tab ↗.
Why you should trust us
We read each vendor's pricing page and help center, checked every price on October 12, 2026, and read the IRS rules on electronic signatures for e file authorizations IRS e signature rules ↗ and its guidance on data security plans for tax professionals IRS data security plan ↗. We also read user reviews on Capterra and G2 Capterra, TaxDome ↗ G2, Canopy ↗.
No vendor paid for placement, and our picks were chosen on merit.
How we picked
We started with the practice management platforms small firms compare most often, and added QuickBooks Online Accountant because many bookkeepers already use its free practice tools.
We judged each on five jobs: getting documents from clients, getting signatures that hold up with the IRS, moving work through recurring checklists, getting paid, and what all of that costs per seat for a small team.
- Client portal with uploads, messaging and mobile access
- E signatures with KBA identity checks
- Recurring workflow templates and automatic client reminders
- Invoicing, recurring billing and online payments
- Published per user or per seat pricing
- Seasonal or flexible seats for tax season
What it costs a three person firm
Here is a year for a firm with three staff on published prices, plus 300 signers who need KBA for e file authorizations.
TaxDome Pro: three seats at $1,000 is $3,000 a year, or $2,700 on a three year term TaxDome plans ↗. E signatures are unlimited, and 300 KBA attempts add about $300 TaxDome plans ↗ TaxDome KBA ↗. Total: about $3,300.
Karbon Team: three users at $59 a month billed yearly is $2,124 a year; a three person firm cannot use monthly billing Karbon pricing ↗. E signature credits are extra, from $100 per 100 Karbon pricing ↗, and the KBA price is not published Karbon e signatures ↗. Total: $2,124 plus signatures. Karbon Business, with task automation, is $3,204 Karbon pricing ↗.
Canopy Standard: three users at $74 a month billed yearly is $2,664 a year, and 300 KBA credits add $375 Canopy pricing ↗. Total: about $3,039, before any Tax Resolution add on at $50 per user a month Canopy pricing ↗.
If you add a fourth person for tax season only, TaxDome's four month Business seasonal seat is $500 TaxDome plans ↗.
IRS rules that shape your choice
E signatures on e file authorizations. When a taxpayer signs Form 8879 remotely, the IRS requires the software to verify identity with knowledge based authentication each time, and to record the signed form image, date and time, IP address, login name and verification result IRS e signature rules ↗. The record must be kept tamper proof for three years IRS e signature rules ↗. If the taxpayer fails three attempts, you need a handwritten signature IRS e signature rules ↗. So check that a platform offers KBA, not just a basic signature.
A written security plan. The IRS says having a written data security plan is federal law under the FTC Safeguards Rule, and that the plan should include overseeing service providers and requiring safeguards in their contracts IRS data security plan ↗. Your practice management vendor holds client tax documents, so add it to your plan and ask for its security documentation.
- Confirm KBA is available for every signer on joint returns
- Ask how long signature audit trails are kept
- List the platform in your written information security plan
- Turn on multi factor sign in for staff and clients
Before you sign up
Switch outside tax season. Moving clients into a new portal in March is how firms end up running two systems. Plan the move for summer or early fall, and invite clients in small batches.
In a demo, ask to see a full client cycle: an organizer request, a document upload from a phone, a KBA signature, an invoice and a payment. Ask what is included and what is billed per use, such as signatures, KBA, payments and AI.
- Price every add on, not just the seat
- Test the client portal on a phone
- Check whether billing is upfront or monthly
- Ask how to export client data if you leave
The competition
QuickBooks OnlineStarts at $38/month (Simple Start)
QuickBooks Online Accountant is free to sign up for and lets you manage client files from one login QuickBooks Online Accountant ↗. Its Work tab handles internal projects and tasks, including repeating projects, and client requests that ask a client to answer a question or upload a document QuickBooks Work tab ↗. The help article does not mention e signatures or billing, so most tax firms will still need a separate tool QuickBooks Work tab ↗.
XeroStarts at $27/month
If your firm works mainly in Xero, ask Xero which practice tools come with its partner program for US firms. We could not confirm current US availability and pricing, so we did not rank them here.
Questions people ask
What is the best practice management software for a small accounting firm?
For most small tax and bookkeeping firms, TaxDome, because the client portal, unlimited e signatures, invoicing and workflows come in every plan TaxDome pricing ↗ TaxDome plans ↗. For bookkeeping firms that live in email, Karbon has the lowest per user price at $59 a month billed yearly Karbon pricing ↗.
How much does accounting practice management software cost?
TaxDome seats run $800 to $1,200 a year TaxDome plans ↗, Karbon $59 to $89 per user a month billed yearly Karbon pricing ↗, and Canopy $74 to $149 per user a month billed yearly Canopy pricing ↗. Add per use costs such as KBA, e signature credits and card fees.
Do I need KBA for e signatures on tax returns?
For remote signatures on Form 8879, yes. The IRS requires identity verification with knowledge based authentication each time a taxpayer signs remotely IRS e signature rules ↗. TaxDome charges $1 per KBA attempt TaxDome KBA ↗, Canopy $1.25 per credit Canopy pricing ↗, and Karbon offers KBA without a published price Karbon e signatures ↗.
Is QuickBooks Online Accountant enough for practice management?
For a solo bookkeeper, it can be. It is free to sign up QuickBooks Online Accountant ↗ and its Work tab tracks projects, tasks and client requests QuickBooks Work tab ↗. It does not mention e signatures or billing in its practice management help, so tax firms usually need more QuickBooks Work tab ↗.
Does Karbon charge for AI?
Not currently. Karbon says its AI is available to all customers at no additional cost and that it will announce any pricing changes in advance Karbon AI ↗. It also says it does not train AI models on your firm's data Karbon AI ↗.
TaxDome vs Karbon: which is better?
TaxDome is stronger on the client side, with unlimited e signatures and a client app included TaxDome plans ↗. Karbon is stronger on email and team workflow, with AI email drafting and summaries included Karbon AI ↗, and costs less per user Karbon pricing ↗. Tax firms usually lean TaxDome; bookkeeping and advisory firms often lean Karbon.
Where this comes from
Checked Oct 9, 2026. Vendor pages describe their own products; independent sources add outside views. Built from 13 sources: the makers' own pages plus independent reviews and user reports. We have not run our own hands on test yet; if we do, the results will appear here.
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