Karbon

Karbon is a practice management platform built specifically for accounting firms and bookkeepers. It has ranked #1 in accounting practice management on G2 for 17 consecutive quarters, and its customer base consistently reports substantial time savings — the company's 2024 Firm Usage Survey (representing 15% of total customers) found an average of 18.5 hours saved per employee per week, which they calculate at roughly $34,305 per employee annually.

What it does

Karbon is built around the idea that accounting work has a predictable shape: recurring engagements, standard deliverables, and a lot of back-and-forth with clients to collect documents and approvals. The platform is designed to systematize that entire cycle.

The workflow engine lets firms build templates for common jobs — tax returns, monthly close, audits, payroll — and roll them out as scheduled work items with tasks pre-assigned by role. Work items aggregate everything related to a job: client emails, notes, internal tasks, documents, and client-facing requests. Managers get a real-time view of where every job stands across the whole team.

The email integration is one of Karbon's more distinctive features. Rather than keeping client emails in individual inboxes, Karbon pulls Gmail and Outlook into the platform and links messages to the relevant client or work item. This gives the whole team visibility into client communication, not just the person who handles that account. Emails can be triaged and assigned to team members directly from within Karbon.

The client-facing side lets firms send automated requests for documents and approvals, with reminders that escalate until clients respond. Clients can securely upload files and complete tasks without needing to log in to a full portal — Karbon can send them tokenized links. There's also a more formal client portal experience for document sharing and communication history.

AI features are woven throughout — Karbon has embedded GPT-based tools for drafting client communications, summarizing work, and automating repetitive tasks, all marketed as a secure integration within the existing workflow.

Pricing

Three tiers, all billed per user:

• Starter — essential workflow and collaboration tools for small firms
• Team — $59/user/month (billed annually), adds workflow automation, scheduling, and integrations
• Business — $89/user/month, adds advanced security, reporting, and collaboration features for larger practices

Monthly billing is available at a higher rate. Quarterly training sessions with a Karbon expert are available as a paid add-on on Team and Business plans. Built-in payments use direct debit at 1% + $0.30 per transaction (capped at $4.00), with an extra 0.2% on payments over $2,000.

Integrations

Karbon integrates with Xero and QuickBooks Online for billing and client data sync, Google Workspace and Microsoft 365 for email and calendar, and Zapier for broader automation. The platform also connects with Aider for AI-assisted bookkeeping, which Karbon has been actively promoting for period-close workflows.

Limitations

The client-facing portal is more utilitarian than what dedicated portal tools offer — there's no white-labeling, no customized client dashboard, and the experience is oriented around task completion rather than a polished branded space. Firms that want a premium portal with custom branding should look elsewhere.

Karbon is also built exclusively for accounting and bookkeeping practices. Other professional services firms — consultants, agencies, legal — won't find it applicable. And the per-user pricing adds up quickly: a 10-person firm on the Business plan is looking at $890/month before add-ons.

Who it's for

Karbon is best suited for established accounting firms (typically 3–50 staff) that are serious about systematizing their workflows and eliminating the chaos of managing client engagements across spreadsheets and email threads. It competes most directly with TaxDome and Financial Cents in the accounting practice management space, but sits above both in workflow sophistication and price. Firms that prioritize internal team coordination and process consistency over client-facing portal aesthetics tend to be its happiest customers.