Best Invoicing Software for Bookkeepers: 11 Tools Ranked for 2026

Bookkeepers have an odd problem. You spend all day inside accounting software billing other people's clients, yet your own invoicing often runs on a spreadsheet, a half-configured QuickBooks file, or a recurring PayPal link. According to the AICPA's 2024 PCPS Practice Management Survey, firms that shifted to fixed-fee or value-based billing for Client Advisory Services (CAS) saw average revenue per client grow 20% or more year over year, while hourly-only firms stagnated. The invoicing tool you pick either supports that shift or fights it.

The IRS reported in its 2024 Tax Gap analysis that small-business underreporting remains the largest share of the gross tax gap, which is a direct reason the bookkeeping category is still growing. The U.S. Bureau of Labor Statistics projects about 174,900 openings for bookkeeping, accounting, and auditing clerks each year through 2033. More clients, more retainers, more monthly-close work — and more pressure to stop billing like a 2005 sole proprietor.

This guide ranks 11 invoicing platforms against what bookkeepers and small accounting firms actually need in 2026: clean retainer billing, batch invoicing across many clients on the same close cycle, real integration with QuickBooks Online and Xero, 1099 contractor support, multi-entity handling for CPAs, and a client portal that does not embarrass the firm. Every price below was verified against the vendor's official pricing page on April 15, 2026.

Quick Comparison: Invoicing Platforms for Bookkeepers

How We Evaluated Each Platform

Bookkeeper workflows differ from freelance or consultant billing in five meaningful ways, and we scored every tool against each one:

1. Retainer and recurring logic — Monthly close clients need invoices on the same date every month, sometimes tiered by transaction count. The tool should auto-generate, auto-send, and auto-retry failed payments.
2. Batch invoicing and bulk actions — A firm with 40 monthly-close clients should not click "Create Invoice" 40 times. Batch creation, batch send, and batch statements are not optional.
3. QuickBooks Online and Xero integration depth — Native two-way sync beats Zapier for tools that touch the accounting ledger. We flagged which are native and which are middleware.
4. Multi-entity and white-label support — A CPA firm with S-corps, LLCs, and sole props under one practice needs to invoice from separate entities without buying a new subscription per EIN. White-label client portals matter for firms that want their brand, not the vendor's.
5. Tax-season readiness — 1099-NEC and 1099-MISC filing, W-9 collection, clean Schedule C or 1120-S export, and quarterly estimated-tax tracking are table-stakes features too many tools still skip.

We also priced each platform on a simulated 25-client monthly-close firm (retainer clients billed $400/month average). Results live in the "Which Platform Costs Least at Scale?" section below.

1. Agiled — Invoicing, CRM, Contracts, and Client Portal in One Platform

Agiled is an all-in-one business management platform built for service firms, and it fits the bookkeeper workflow better than most tools marketed specifically to accountants. The reason is simple: bookkeepers sell a recurring service with a proposal, a signed engagement letter, tracked work, and monthly invoices. Agiled handles all four inside one system instead of stitching three apps together.

Invoicing features for bookkeepers:

• Recurring invoices on weekly, monthly, quarterly, or annual cycles, with per-client send dates (useful when one client wants the 1st and another wants the 5th)
• Retainer tracking so you can invoice a fixed monthly amount and show hours consumed against it on the same invoice
• Branded invoices with your firm logo, line items, sales tax handling, tax IDs (EIN, GST, VAT), and custom fields
• Estimates and proposals that convert to invoices with one click after client e-signature
• Online payments through Stripe, PayPal, Authorize.Net, and Mollie, with automatic reconciliation back to the invoice
• Automated payment reminders at configurable intervals (7, 14, 30 days past due) with optional late-fee rules per client
• Multi-currency support with automatic FX for firms that serve non-US clients
• Expense tracking linked to clients or projects, useful for billing back reimbursable expenses
• Financial reports: invoice aging, revenue by client, revenue by service, profit and loss

Why bookkeepers and firms choose it:

Three reasons stand out. First, the proposal and e-signature workflow means you can send an engagement letter, get it signed, and start billing without leaving the platform. Engagement-letter-to-invoice in the same system closes the loop most accounting-only tools leave open.

Second, the CRM module tracks prospect pipeline, lead source, and communication history. A firm running client advisory services needs to know which leads came from which CPA referral, what's in the proposal stage, and which current clients are at-risk renewal. Pure invoicing tools do not do this.

Third, the white-labeled client portal lets clients view their invoices, approve proposals, pay balances, and see project updates in a space that carries your firm's branding, not Agiled's. For CAS-focused firms that bill $500 to $3,000 per month per client, the client portal experience matters. Clients do not want to be redirected to a third-party payment URL.

QuickBooks and Xero sync: Agiled syncs to QuickBooks Online through Zapier and direct integrations for contacts, invoices, and payments. If your firm lives natively inside QBO for its own books, this is worth testing during the free trial. For firms that use Agiled as their primary operations layer and send only clean invoice totals to QBO monthly, the Zapier bridge is typically sufficient.

Pricing: Free plan with 2 clients and basic invoicing. Solo at $15/month (annual) for unlimited invoicing and project tracking. Pro at $25/month for unlimited contacts, projects, and automations. Premium at $49/month adds proposals, contracts, e-signatures, and white-label branding.

Best for: Solo bookkeepers and firms of 2 to 10 people who want one platform for invoicing, CRM, contracts, and client portal. Especially strong for CAS-focused firms that sell fixed-fee monthly packages.

Tradeoff: If you require first-party, direct API sync to QuickBooks Online with deep chart-of-accounts mapping, Bill.com or native QBO Billing is a closer fit.

Start your free Agiled trial — no credit card required.

2. FreshBooks — Cleanest Invoicing UX for Mixed Hourly and Fixed-Fee Work

FreshBooks built its reputation on making invoicing painless for non-accountants, which is ironic because many bookkeepers now use it for their own books. The interface prioritizes speed: creating and sending an invoice takes under 60 seconds, and the mobile app handles the same workflow without losing features.

Key features for bookkeepers:

• Unlimited invoices on all paid plans
• Built-in time tracking with a one-tap timer, idle-time detection, and project-level rates
• Recurring invoice profiles for monthly retainer clients
• Automated late fees and payment reminders
• Proposals and estimates that convert to invoices
• Native integrations with QuickBooks Online and Xero for two-way contact and invoice sync
• Team collaboration with role-based permissions (useful when a firm assigns an associate to a client)
• 1099 contractor reports for firms that also pay subcontractors

Bookkeeper-specific strengths:

FreshBooks has a dedicated accountant and bookkeeper partner program. Firms that enroll get a central dashboard across all client FreshBooks accounts, along with discounted pricing for their own practice. If you manage multiple clients who use FreshBooks for their day-to-day, this consolidation is meaningful.

The retainer module lets you set a monthly retainer amount and track billable hours consumed against it. At month-end you can show the client the retainer balance, hours used, and any overage billed at the hourly rate — without manual calculation.

Pricing: Lite at $21/month (5 billable clients), Plus at $38/month (50 clients), Premium at $65/month (unlimited clients), Select for larger firms at custom pricing. Payment processing is 2.9% plus $0.30 for card, 1% for ACH.

Tradeoff: The 5-client cap on Lite pushes most bookkeepers to Plus immediately, making the real entry price $38/month. Also, while FreshBooks has an accounting module, it is light compared with QBO or Xero — most firms use FreshBooks for billing and QBO/Xero for books.

3. QuickBooks Online — Native Billing Inside the Ledger Your Clients Already Use

If your firm lives inside QuickBooks Online for its own books, the cleanest path is to invoice from QBO directly. No sync, no middleware, no reconciliation headaches. Every invoice, payment, and client is already in the same database as your chart of accounts, bank feeds, and tax reports.

Invoicing features:

• Recurring invoices with flexible schedules
• Progress invoicing (partial billing against an estimate)
• Automated payment reminders with customizable cadence
• QuickBooks Payments for card and ACH, with clients able to pay from the invoice email
• Batch invoicing (Plus and Advanced plans) for firms sending similar invoices to many clients
• Multi-currency on the Essentials plan and above
• Integrated 1099-NEC filing for contractors at tax time

Firm-specific tools:

QuickBooks Online Accountant is free for bookkeepers and gives you a client list dashboard, work management (task tracking), and wholesale billing — where Intuit bills the firm, the firm bills the client, and the firm keeps the margin. For firms managing 10+ client QBO subscriptions, wholesale pricing meaningfully improves gross margin.

Pricing (for your firm's own QBO subscription): Simple Start $38/month, Essentials $75/month, Plus $115/month, Advanced $275/month. QBO Payments card rates are 2.99% keyed, 2.5% swiped, 3.5% invoiced; ACH is 1% capped at $10.

Tradeoff: QuickBooks Online is priced per-entity. A firm with multiple entities (its operating company plus a holding LLC) pays twice. For purely invoicing workflows, QBO is heavier and more expensive than Agiled, FreshBooks, or Zoho Invoice. Use it when you already need the full accounting ledger; skip it if you just need to send invoices.

4. Xero — Strong Repeating Invoices and a Tight Partner Program

Xero is the default choice for non-US firms and for a growing segment of US firms that dislike Intuit's pricing. For bookkeeper-sent invoices, Xero's "repeating invoices" are reliable, and its partner program gives firms a central advisor console across all client Xero files.

Invoicing features:

• Repeating invoice templates with flexible frequencies
• Online invoicing with pay-now buttons via Stripe, GoCardless, and regional gateways
• Bulk invoice creation for firms billing a similar amount to many clients
• Automated invoice reminders
• Multi-currency on the Established plan
• Native 1099 tracking for US accounts; GST/VAT handling for non-US

Firm-specific tools:

Xero's partner program (free for advisors) unlocks Xero HQ, a practice management dashboard with a central client list, bulk actions, and staff management. Xero also owns Xero Practice Manager for time tracking and job management across staff, though pricing is separate.

Pricing (US): Early at $20/month (20 invoices/month limit), Growing at $47/month, Established at $80/month. Partner program clients get discounted rates depending on tier.

Tradeoff: The Early plan's 20-invoice monthly cap is aggressive. A bookkeeper with 20+ clients on monthly close hits the ceiling on day one. Most firms start on Growing immediately, making the effective entry price $47/month. Also, Xero's US payment processing is not as seamless as QBO Payments in the QBO ecosystem.

5. Zoho Invoice — Free Invoicing for International Bookkeepers on Tight Budgets

Zoho Invoice is the only genuinely free, no-transaction-cap invoicing tool on this list with serious international features. For bookkeepers who serve overseas clients or work from outside the US, Zoho Invoice handles multi-currency, VAT, GST, and per-region tax IDs out of the box.

Key features:

• Unlimited invoices, estimates, and clients on the free plan (up to 1,000 invoices per year)
• Recurring profiles with start date, end date, and auto-send logic
• Multi-currency with automatic FX rates
• Customer portal for clients to view and pay invoices
• Time tracking with billable-hours conversion to invoices
• Expense tracking with receipt attachments
• Automated payment reminders and late fees
• Integrations with Zoho Books, Zoho CRM, and 40+ other apps

Bookkeeper-specific strengths:

If you also run Zoho Books for a client's bookkeeping, Zoho Invoice data flows into Zoho Books natively. For firms that have adopted Zoho One as a back office (CRM, projects, invoicing, HR), the consolidation is efficient.

Pricing: Zoho Invoice is free. Zoho Books (full accounting) starts at $20/month. Zoho One (45+ apps bundled) is $37/user/month.

Tradeoff: The 1,000-invoice annual cap on the free plan is generous for solo bookkeepers but will bind a mid-size firm. Native sync with QuickBooks Online and Xero is limited — Zoho's gravity is inside its own ecosystem.

6. Wave — Free Invoicing for Solo Bookkeepers With Simple Billing

Wave offers free invoicing, free estimates, and free accounting. For a solo bookkeeper running 10 to 15 clients on simple monthly retainers, Wave does the basics well at $0/month.

Key features:

• Unlimited invoices, customers, and estimates on the free plan
• Recurring invoices with automated reminders
• Online payments via Stripe integration
• Multi-user access (Wave Pro at $16/month)
• Simple accounting with bank feed imports
• Receipt scanning on mobile
• US and Canada only

Tradeoff: Wave does not sync with QuickBooks Online or Xero. If your firm or your clients live in QBO, Wave creates a silo. Payment processing fees are also higher than average: 2.9% plus $0.60 per transaction (the $0.60 is notable versus the $0.30 standard elsewhere). No multi-currency for sending invoices. US and Canada only.

Wave works well as a pure budget choice for domestic bookkeepers whose workflow does not touch QBO or Xero. It does not scale for firms.

7. Bonsai — Invoicing Plus Contracts and Proposals for Solo Bookkeepers

Bonsai is built for solo service providers — originally freelancers — and fits solo bookkeepers who want contracts, proposals, and invoicing in one place. The engagement-letter-to-invoice flow is tight, and the contract templates include service-business defaults that cover most bookkeeping arrangements.

Key features:

• Recurring invoices with automated sends
• Proposals and contracts with e-signatures
• Time tracking linked to invoices
• Expense tracking
• Client CRM
• QuickBooks Online integration on the Business plan
• Automated payment reminders and late fees
• US tax estimator (quarterly estimates)

Pricing: Starter at $25/month, Professional at $39/month, Business at $79/month (QBO sync included at Business).

Tradeoff: Bonsai's US tax features are stronger than its international handling. UK and EU bookkeepers will find more ecosystem gravity in Xero or Zoho. Also, QBO sync is gated behind the Business plan.

8. Invoice Ninja — Open-Source Invoicing for Technical Bookkeepers

Invoice Ninja is the open-source option on this list. Bookkeepers with technical skills (or an IT-capable partner) can self-host it on their own server for full control, or use the hosted cloud version with simpler setup.

Key features:

• Unlimited invoices and clients on the free cloud plan
• Recurring invoice profiles
• Multi-currency
• Client portal with payment processing
• Proposals and quotes
• Time tracking
• Expense tracking
• Self-host or cloud deployment
• 40+ payment gateway integrations

Pricing: Free forever plan; Ninja Pro at $12/month (annual) or $16/month; self-hosted is free plus infrastructure costs.

Tradeoff: Self-hosting needs server administration skills, backup discipline, and security hygiene. For the bookkeeper who wants open-source freedom and does not mind doing the IT, Invoice Ninja delivers. For everyone else, the cloud version is cleaner but gives up the full control argument that is Invoice Ninja's reason for existing.

9. Harvest — Retainer Billing Built for Firms That Bill Strict Hourly

Harvest is narrower than the other tools on this list, but for firms that bill strict hourly or mixed hourly-plus-retainer work, the retainer module is the cleanest on the market. You set a monthly retainer amount, track hours against it, and the invoice shows balance, hours used, and overage automatically.

Key features:

• Time tracking across desktop, mobile, and browser extension
• Retainer tracking with balance carryover logic
• Invoice generation from tracked time
• Team time reports
• Native QuickBooks Online and Xero integrations
• Project budget alerts
• Approval workflows for timesheet submission

Pricing: Free for 1 user and 2 projects; Pro at $13.75/user/month (annual) for unlimited projects.

Tradeoff: Harvest's invoicing is functional but basic — no proposals, no CRM, minimal design customization. Firms that want one platform for invoicing, CRM, and contracts will find Harvest too narrow. Firms that already use a CRM and just need tight retainer-to-invoice logic love it.

10. Bill.com — AR and AP Automation for Firms Running Client Books

Bill.com sits in a different category from the rest of this list. It is AR and AP automation at scale, built for accounting firms that run the billing side for their clients, not just their own practice. If your firm collects payments from your clients' customers as part of CAS work, Bill.com is the standard.

Key features:

• Accounts receivable with recurring invoices and online payments
• Accounts payable with bill capture, approval workflows, and ACH payments
• Native sync with QuickBooks Online, Xero, Sage Intacct, and NetSuite
• Multi-entity support (critical for firms running multiple client books)
• Bill.com Accountant Partner Program with wholesale pricing and a central firm dashboard
• 1099 contractor management with W-9 collection and year-end filing
• Audit trail and role-based approval for SOX-sensitive clients

Pricing: Essentials at $45/user/month for AR or AP alone; Corporate at $55/user/month for AR and AP combined; Enterprise custom. Partner Program pricing for firms is discounted and firm-billed.

Tradeoff: Bill.com is priced for firms, not solos. A one-person bookkeeper billing their own clients will find it heavy and expensive. For a 5+ person firm that runs AP for many clients, Bill.com pays for itself in hours saved on bill capture and approval routing.

11. Sage Intacct — Contract Billing for Multi-Entity CPA Firms

Sage Intacct is a cloud financial-management platform used by multi-entity CPA firms, larger bookkeeping firms, and growing businesses that outgrew QuickBooks. For firms billing many clients across many entities with complex contract terms (tiered, milestone, usage-based), Intacct's contract revenue management is the serious answer.

Key features:

• Contract and subscription billing with ASC 606-compliant revenue recognition
• Multi-entity consolidation across unlimited entities
• Dimensional reporting (by client, by service, by staff, by location)
• Native AR and AP with automation
• Native integrations with Salesforce, Bill.com, Expensify, and ADP
• Role-based permissions with SOX-ready audit trails

Pricing: Custom quote only. Typical entry is $400 to $1,000 per month per entity for mid-market, scaling with users, modules, and entity count.

Tradeoff: Intacct is enterprise-priced and enterprise-complex. Implementation runs weeks to months and typically requires an implementation partner. For firms under 10 staff and under 100 clients, it is overkill. For a 20-person CPA firm running multi-entity CAS work at scale, it is often the only tool that actually fits.

Which Platform Costs Least at Scale?

Run the math on a 25-client monthly-close firm billing an average $400/month retainer per client ($120,000 annual revenue). Assume the firm processes 60% of payments via card and 40% via ACH.

The spread is roughly $1,100 a year between the cheapest and most expensive — meaningful but smaller than the productivity delta. A tool that saves two hours a month on retainer invoice creation is worth more than the processing-fee difference at this firm size. Pick for workflow fit first, then negotiate payment processing separately if card volume grows.

How Bookkeepers Should Think About Retainer vs. Value-Based Billing

The AICPA's Client Advisory Services benchmarking shows firms shifting from hourly billing to fixed-fee or value-based billing grow faster and retain clients longer. The invoicing tool matters because these models put different pressure on the software:

• Pure hourly — You need accurate time tracking, clean hours-to-invoice conversion, and rate management per staff. Harvest, FreshBooks, and Agiled all handle this well.
• Fixed-fee retainer — You need recurring invoice profiles, payment-method-on-file for auto-charge, and failed-payment retry logic. Agiled, FreshBooks, QuickBooks Online, and Xero all handle this.
• Tiered / packaged CAS — Bronze, Silver, Gold packages at set monthly rates require client-level plan tracking and upgrade/downgrade logic. Agiled, Bonsai, and Bill.com handle tiered packages cleanly.
• Value-based (project or outcome) — Less recurring, more proposal-driven. You need proposals, e-signatures, milestone invoicing, and contract storage. Agiled and Bonsai are strongest here.

If your firm is transitioning from hourly to fixed-fee, pick a tool that supports both billing modes in parallel. You will have legacy hourly clients for months before everyone converts.

Features Every Bookkeeper Invoicing Tool Should Have in 2026

Use this checklist when you shortlist:

• Recurring invoice profiles with per-client send dates
• Payment-method-on-file with auto-charge for retainer clients
• Failed-payment retry with client notification
• Automated late-fee rules configurable per client
• Native or Zapier sync to QuickBooks Online or Xero
• Client portal for invoice history and payment
• Proposal and e-signature flow for engagement letters
• Batch invoice creation for month-end close cycles
• 1099-NEC and W-9 handling
• Multi-currency (if you serve any non-US clients)
• Role-based permissions (if your firm has 2+ staff)
• White-label branding on client-facing pages (firm-grade)

Tools that miss more than two of these force workarounds you will regret by month three.

When Invoicing Software Is the Wrong Answer (Not For You)

Three scenarios where installing any of the tools above makes things worse rather than better:

You run a pure tax-prep practice with no monthly clients. If 95% of your revenue is 1040 prep in March and April, you need tax software billing (Drake, Lacerte, ProConnect) not a CAS-oriented tool. Pay per return, collect at filing, skip the monthly close machinery.

You bill fewer than 8 clients and all pay the same flat amount monthly. A Stripe Subscription or a QuickBooks Online recurring invoice is enough. The overhead of a dedicated invoicing platform does not pay for itself until you cross roughly 15 active clients, multiple billing models, or multiple entities.

You are a controller-level fractional CFO charging $200 to $400 an hour. Your problem is not invoice generation, it is contract scoping, scope creep, and collection from clients whose AP departments slow-pay everyone. A proposal tool (PandaDoc, Proposify) plus AR automation (Bill.com or Upflow) will do more for cash flow than a better invoice template.

Original Research: Retainer-Payment Success Rates by Payment Method

We compared failed-payment rates across three common retainer payment methods based on publicly disclosed processor benchmarks and firm anecdotes from r/Bookkeeping and r/Accounting threads spanning the last 18 months. The pattern is consistent enough to plan around.

The practical takeaway: put every new retainer client on ACH auto-debit from day one. Card auto-charge fails 3 to 5 times more often, and the failure usually clusters around card expiration dates (month-end, month-start) — exactly when your close-cycle invoices go out. Tools like Agiled, Bill.com, FreshBooks, and QuickBooks Online all support both methods; Wave and Zoho Invoice rely on the underlying processor's retry behavior.

Frequently Asked Questions

What is the best invoicing software for a solo bookkeeper?

For a solo bookkeeper billing 10 to 30 monthly-close clients, Agiled covers invoicing, proposals, contracts, and client portal under one subscription and handles recurring billing cleanly. FreshBooks is the strongest pure-invoicing alternative with better native QuickBooks Online sync. Zoho Invoice is the best free option if you stay under 1,000 invoices a year and do not need deep QBO integration.

Do bookkeepers need QuickBooks or can they use a separate invoicing tool?

Bookkeepers do not have to invoice their own clients from QuickBooks Online. Many firms keep QBO for accounting and use a lighter tool — Agiled, FreshBooks, or Bonsai — for billing, then post monthly invoice totals to QBO via integration or journal entry. Using QBO as both the firm's ledger and its billing tool is convenient but pushes you toward the $75 to $115/month plans when a $25/month billing tool plus a $20/month QBO Simple Start would do the same work.

How do bookkeepers bill for monthly retainer clients?

Most firms use recurring invoice profiles set to auto-generate and auto-send on a fixed day (commonly the 1st or the 5th of the month) with payment-method-on-file for auto-charge. ACH auto-debit is the default for retainers above $500/month because card decline rates run 3 to 5 times higher than ACH. Tools that support failed-payment retry logic — Agiled, FreshBooks, QuickBooks Online, Bill.com — meaningfully reduce follow-up work on failed auto-charges.

What invoicing software integrates with QuickBooks Online for bookkeepers?

Native two-way integrations with QuickBooks Online are available in FreshBooks, Xero (limited for invoice export), Bill.com, Harvest, and Bonsai Business. Agiled and Invoice Ninja connect via Zapier, which is adequate for invoice totals and contact sync but thinner than a direct API integration for line-item chart-of-accounts mapping.

Can one invoicing tool handle multiple entities for a CPA firm?

Most solo-focused tools (FreshBooks, Bonsai, Wave) treat one subscription as one entity. For firms that need to invoice from multiple EINs — an operating company and a holding LLC, for example — Bill.com, Sage Intacct, and QuickBooks Online Advanced handle multi-entity natively. Agiled supports multi-entity through workspaces on Pro and Premium plans.

What is the cheapest invoicing software for accountants?

Zoho Invoice is free for up to 1,000 invoices per year, which covers almost any solo bookkeeper. Wave is free for unlimited invoicing but US and Canada only and without QBO or Xero sync. Invoice Ninja's free cloud plan is unlimited and supports multi-currency. For firms needing a deeper feature set (contracts, proposals, CRM), Agiled's Solo plan at $15/month is the cheapest all-in-one.

How do bookkeepers handle 1099 contractors inside their invoicing tool?

Most dedicated invoicing tools do not handle 1099 filing end-to-end. The standard workflow is: collect W-9s during client onboarding (store inside the invoicing tool or CRM), track contractor payments in QuickBooks Online or Xero (both handle 1099-NEC reporting natively), and file 1099s through QBO, Track1099, Tax1099, or Bill.com at year-end. Bill.com's contractor management is the most automated for firms that pay many contractors on behalf of clients.

Final Recommendation

For most solo bookkeepers and small firms in 2026, the practical shortlist is three tools:

• Agiled — if you want one platform for invoicing, proposals, contracts, CRM, and client portal, and you are comfortable with Zapier-based QuickBooks sync. Strongest value at $25 to $49/month for the feature depth.
• FreshBooks — if native QuickBooks Online sync is non-negotiable and you mostly bill a mix of hourly and fixed-fee clients. Strong invoice UX, solid retainer module, partner program for firms.
• Bill.com — if your firm is 5+ people running AR and AP for many clients, especially with multi-entity needs. Priced for firms, pays for itself at scale.

For firms billing more than 50 clients across multiple entities, or firms with complex contract revenue recognition, Sage Intacct is the serious answer even at the higher price and longer implementation.

Start with a free trial of Agiled if you want to test the all-in-one approach, and compare against a FreshBooks or Bill.com trial in parallel. Most firms switch billing tools once every 3 to 5 years, so the decision deserves two weeks of side-by-side evaluation, not one demo call.