Best Accounting & Invoicing Software for Consulting Firms in 2026
Consulting firms sell time and expertise, which means their accounting revolves around a deceptively simple question: are we billing all the time we spend, and is that time profitable? Time tracking accuracy, retainer billing, project-based invoicing, and expense reimbursement are the core workflows that separate consulting accounting from generic small business bookkeeping. Add in multi-consultant payroll with varying rates and bonus structures, and the accounting complexity grows quickly. The right software connects time tracked directly to invoices generated, ensures retainer balances are accurately tracked, and gives principals visibility into revenue per project and per consultant.
Last updated: 2026-04-23
QuickBooks Online
The most widely used accounting platform for professional services firms, with time tracking, project billing, and payroll in one system.
Why it fits this industry
QuickBooks Online Plus includes billable time tracking — consultants log hours tagged to specific clients, which then populate invoice line items automatically. The Projects feature tracks revenue, labor cost, and expenses per engagement, giving principals a clear view of project profitability. Retainer billing is handled through pre-payment invoices with balance tracking. QuickBooks Payroll handles multi-consultant compensation including salary, bonuses, and owner draws.
Pros
- ✓Built-in billable time tracking that flows directly to client invoices
- ✓Projects feature tracks profitability per engagement
- ✓Retainer billing with pre-payment invoices and balance management
- ✓QuickBooks Payroll handles varied consultant compensation structures
Cons
- ✕Time tracking is basic — serious consulting firms often use dedicated tools like Harvest
- ✕Project billing only available on Plus plan
- ✕Payroll add-on increases monthly cost significantly
Pricing: Simple Start $35/month; Plus $65/month; Payroll add-on from $45/month + $6/employee
Best for consulting firms that want all-in-one accounting, invoicing, time tracking, and payroll in a single widely understood platform.
FreshBooks
Invoicing and accounting software specifically designed for service businesses and freelancers, with strong time tracking and project billing.
Why it fits this industry
FreshBooks was built for professional service businesses — the interface optimizes for the time-tracking-to-invoice workflow that consultants live in. Consultants log time against projects or clients; FreshBooks converts logged hours into invoice line items with a single click. Retainer management, expense reimbursement on client invoices, and a clean client portal for invoice approval and payment are all native features.
Pros
- ✓Industry-leading time tracking to invoice conversion workflow
- ✓Retainer management with balance tracking
- ✓Expense reimbursement on client invoices with receipt attachment
- ✓Clean client portal for invoice review and payment
Cons
- ✕Full-service payroll requires third-party integration
- ✕Reporting is less comprehensive than QuickBooks for multi-consultant firms
- ✕Team collaboration features improve at higher plan tiers only
Pricing: Lite $19/month; Plus $33/month; Premium $60/month
Best for boutique consulting firms and independent consultants who prioritize a seamless time-to-invoice workflow with strong client invoicing.
Harvest
Time tracking and invoicing tool built for professional services teams, with project budget monitoring and QuickBooks/Xero integration.
Why it fits this industry
Harvest occupies a unique position for consulting firms: it focuses entirely on time tracking and project billing, and does it better than any general accounting tool. Consultants log time by project and task; Harvest tracks budget burn in real time, alerting project managers before engagements go over budget. Invoices generate from tracked time automatically. For accounting, Harvest integrates with QuickBooks Online and Xero.
Pros
- ✓Best-in-class time tracking for consulting teams
- ✓Real-time project budget monitoring with over-budget alerts
- ✓Team utilization and capacity reporting
- ✓Clean QuickBooks and Xero integration for accounting
Cons
- ✕Not a full accounting system — requires QuickBooks or Xero for accounting
- ✕No payroll
- ✕Adds another monthly subscription to the software stack
- ✕Overkill for solo consultants who only need basic time tracking
Pricing: Free for 1 user, 2 projects; Pro $13.75/user/month
Best for consulting firms with multiple consultants that need serious project budget tracking and team utilization reporting alongside accounting.
Xero
Cloud accounting software with project tracking and unlimited users, a strong choice for consulting firms that prefer it over QuickBooks.
Why it fits this industry
Xero Projects (available on the Business plan) combines time tracking, expense tracking, and project-level invoicing in a clean interface. For consulting firms that have an existing preference for Xero or want unlimited user access without per-seat fees, Xero handles the core project billing and accounting workflow. The unlimited-user model particularly benefits firms where multiple consultants need to log time and check their project status.
Pros
- ✓Xero Projects includes time tracking and project billing
- ✓Unlimited users on all plans — no cost for adding consultants
- ✓Strong bank reconciliation and accounting back-end
- ✓Gusto integration for multi-consultant payroll
Cons
- ✕Xero Projects adds extra cost on Business plan
- ✕Project tracking less feature-rich than dedicated tools like Harvest
- ✕Payroll requires Gusto or another third-party add-on
Pricing: Starter $20/month; Standard $47/month; Premium $80/month (Projects included on Business plan)
Best for consulting firms with multiple consultants that want unlimited user access and a single platform for project tracking and accounting.
Bonsai
All-in-one platform for independent consultants and small firms combining contracts, proposals, time tracking, and invoicing.
Why it fits this industry
Bonsai is designed specifically for independent consultants and boutique firms. It handles the full client lifecycle: proposals, contracts with e-signatures, time tracking, project billing, and invoicing in one integrated tool. For solo consultants or firms with 2-5 people who want to manage client relationships and billing without a separate accounting system, Bonsai eliminates tool sprawl.
Pros
- ✓Combines contracts, proposals, time tracking, and invoicing in one tool
- ✓E-signature contracts reduce project start delays
- ✓Built specifically for consultants and freelancers
- ✓Automated invoice reminders reduce overdue payments
Cons
- ✕Not a full accounting system — tax reporting and payroll require QuickBooks or an accountant
- ✕Less suitable for larger firms with complex multi-project billing
- ✕Accounting depth limited compared to QuickBooks or Xero
Pricing: Starter $21/month; Professional $32/month; Business $66/month
Best for solo consultants and small boutique firms that want contracts, invoicing, and time tracking in one tool without managing multiple subscriptions.
Buyer's Guide
Consulting firm accounting centers on one core discipline: billing all the work you do. Utilization rate — the percentage of consultant hours that are billable to clients — is the most important financial KPI in consulting, and the only way to track it accurately is through disciplined time logging. Before choosing accounting software, decide whether you want time tracking built into your accounting tool (QuickBooks, FreshBooks, Xero) or as a separate purpose-built layer (Harvest). Dedicated time tracking tools generally produce more accurate data because they make logging time easy from any device and send reminders. The trade-off is managing two subscriptions and an integration. For solo consultants or small boutique firms, FreshBooks or Bonsai simplify the workflow by combining the key pieces. For larger firms with multiple consultants and complex project billing, Harvest plus QuickBooks or Xero is the professional standard. Retainer management deserves specific attention: ensure your chosen software can track retainer balances accurately — how much was pre-billed, how much has been earned, and how much remains — so that retainer billing stays clean.