Invoice software forProfessional Services

    Bill by the hour, the retainer, or the phase, and get paid without chasing a single client for a status update.

    Start free 14-day trialNo credit card required.
    Billing Models3 clients
    • Ashcroft & Reyes BookkeepingRetainer
    • Marlow Architecture StudioPhase
    • Priya Nandan, RealtorOne-off
    RecordOne client
    INV-0148Paid
    INV-0149Pending

    The Problem

    Why professional services billing doesn't fit one invoice format

    Professional services firms bill in more different ways than almost any other category. A bookkeeper might run a monthly retainer for one client and a one-off engagement for a single tax return. An architect bills in phases tied to project deliverables: a deposit, a payment at each design stage, a final invoice on handover. A real estate agent doesn't bill on a schedule at all, the invoice happens once, the moment a deal closes, for a commission or service fee.

    Generic invoicing tools tend to assume one billing rhythm fits every client. That works until a retainer client needs a one-off invoice for extra work, or a project moves into its next phase and last month's invoice format doesn't carry over cleanly. The result is rebuilding the invoice from scratch every time, or running two different tools depending on how a given client is billed.

    The bigger cost shows up in cash flow. When a firm's own billing takes a back seat to client deadlines, a busy tax season, a project milestone, a closing date, invoices tend to go out later than planned. Late invoices mean late payments, and for firms carrying staff and overhead, that delay is felt fast.

    What Alfaa Handles

    What Alfaa handles for professional services firms

    Bill however each client pays

    Set up hourly, retainer, or one-off billing per client, not per account. A bookkeeping retainer, a staged architecture project, and a one-time real estate commission can all sit in the same workspace without switching tools.

    Retainers that send themselves

    Set up automatic billing for a bookkeeping or advisory retainer, so invoices go out on schedule without manual follow-up.

    Phase and milestone invoicing

    Bill a deposit, a progress payment tied to a completed phase, and a final invoice separately as a project moves forward, all tied to the same client and project record.

    One-off invoices the moment work concludes

    Raise a single invoice the moment a tax engagement wraps, a transaction closes, or a project is delivered, without rebuilding the invoice format from scratch.

    One record per client, regardless of engagement type

    Every client's invoice history lives in one place, whether they're on a retainer, billed by phase, or invoiced once for a closed deal.

    Invoices that look like they came from you

    Send through Gmail, Google Workspace, or your own domain, so clients see your firm's name, not a generic billing platform address.

    How It Works

    How professional services firms actually use Alfaa

    Retainer

    Setting up a retainer client

    Add a bookkeeping or advisory client once, set the retainer amount and billing date, and the invoice sends itself every cycle from that point on.

    Phase

    Billing a project in phases

    Raise a deposit invoice when a project kicks off, a progress invoice at each completed phase, and a final invoice on delivery, all under the same client and project record.

    One-off

    Invoicing the moment a deal closes

    Create a single invoice for a commission or service fee as soon as a transaction is final, tied to the same client record as any other work you've billed them for.

    Switching to Alfaa

    Switching from spreadsheets or a single-format invoicing tool

    Most professional services firms come to Alfaa from one of two places: accounting or practice-management software that isn't really built for client billing, or a spreadsheet-and-template setup that gets harder to manage once retainer, staged, and one-off invoices start mixing on the same client list.

    The shift away from a rigid or single-format tool is about flexibility, not having to force a real estate commission into a retainer template, or an architecture phase payment into a one-off invoice format. The shift away from spreadsheets is about not losing track of what's been billed and what's still outstanding once there's more than a handful of active clients and engagement types.

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    Who This Is For

    Made for how professional services firms bill

    Accounting and bookkeeping firms

    Architects and design firms

    Billing project phases with staged payments tied to deliverables.

    Real estate agents and brokers

    Invoicing commissions and service fees the moment a deal closes.

    Any professional services firm

    Managing more than one billing model, hourly, retainer, staged, or one-off, across a growing client list.

    At Every Stage

    Built for professional services firms at every stage

    For firms testing the workflow

    Run your first retainer, staged, or one-off invoices during the 14-day trial before committing to a plan.

    For firms with a growing client list

    Manage a mix of retainer, staged, and one-off billing across more clients without the manual overhead scaling right along with them.

    For firms running multiple engagement types at once

    Keep retainer, phase, and one-off billing organized in one place instead of juggling separate templates or tools per engagement type.

    Frequently Asked Questions

    Everything you need to know about invoicing for professional services firms

    The best invoicing software for professional services firms supports retainer, phase-based, and one-off billing, since accounting, architecture, and real estate practices typically use more than one billing model depending on the engagement. Alfaa handles all three from one dashboard.

    Yes. Each client's billing method is set independently, so a retainer bookkeeping client and a one-off real estate commission can both be managed from the same workspace.

    Yes. Each phase or milestone can be raised as a separate invoice tied to the same client and project record.

    No. Alfaa handles invoicing and billing, not bookkeeping, tax preparation, or accounting. Most firms, accounting firms included, run it alongside their existing accounting software for client-facing billing specifically.

    Yes. Set the amount, client, and billing date once, and Alfaa generates and sends the invoice automatically every cycle.

    Stop rebuilding your invoice format every time an engagement type changes

    Start billing retainer, staged, and one-off work from one platform.

    Start free trial

    No credit card required · 14-day free trial · Retainer, phase & one-off billing

    Billing Models3 clients
    • RetainerActive
    • PhaseActive
    • One-offActive