Architect Invoice Template: Phase Billing and Fees

Quick answer: An architect invoice template should bill the basic fee by phase: schematic design, design development, construction documents, procurement and construction administration. For each phase, show the phase fee, percent complete, fee earned to date, previously billed and amount due, then add additional services, reimbursable expenses and any retainer credit.

Architectural projects run for months or years, and clients pay as the work progresses. That makes the architect's invoice less a one-time bill and more a running statement of how much of the fee has been earned. An invoice that only says "Professional services, March: $24,000" forces the client to trust your number. A good architect invoice template shows how you got there, phase by phase.

This guide explains the common fee structures, the standard design phases referenced in AIA agreements, how to calculate percent-complete billing, how to handle reimbursables and additional services, and what a complete progress invoice looks like with the math laid out.

Architect fee structures

The owner-architect agreement sets the fee basis. Most firms use one of the models below or a combination, for example a fixed fee for basic services plus hourly for additional services. Figures are left out because fees vary by project type, size, complexity and region.

Fee model	How it works	How it appears on the invoice
Stipulated sum (fixed fee)	A fixed amount for defined services, split across phases	Phase fee x percent complete, less previously billed
Percentage of construction cost	Fee equals a percentage of the cost of the work, adjusted as estimates change	Cost basis x fee percentage, then split by phase
Hourly	Time billed at rates by staff category	Hours by role x rate, grouped by phase or task
Hourly not to exceed	Hourly billing with a cap	Hours x rate, with billed to date and remaining cap shown
Multiple of direct salary	Direct personnel expense times an agreed multiplier	Labor cost x multiplier, often with timesheet backup
Per square foot or per unit	Fee per area or per dwelling unit, common in repeat building types	Area or units x rate, then split by phase

Fixed fees and percentage-of-cost fees are usually billed on percent complete. Hourly arrangements are billed on actual time, often with the same phase breakdown so the client can compare progress to budget. If you also work as a consultant to other architects or developers, our consulting invoice template guide covers hourly and retainer layouts that translate well.

Design phases in AIA contracts

In the United States, many projects use agreements published by the American Institute of Architects. The widely used AIA Contract Documents B101 owner-architect agreement organizes basic services into five phases:

1. Schematic design (SD). Concept options, site and massing studies, preliminary plans and a preliminary cost estimate.
2. Design development (DD). Refined plans, sections and elevations, major systems and materials selected, an updated estimate.
3. Construction documents (CD). Detailed drawings and specifications used for permitting, pricing and construction.
4. Procurement. Assisting the owner with bidding or negotiation and contractor selection. Older editions called this phase bidding or negotiation.
5. Construction phase services (CA). Site visits, submittal and RFI review, reviewing the contractor's payment applications and certifying completion.

The contract assigns each phase a share of the total fee. The AIA does not prescribe the percentages. A commonly cited illustrative split is about 15% SD, 20% DD, 40% CD, 5% procurement and 20% CA, but firms shift weight according to project type and where their time is actually spent. Use your own completed projects as the guide.

Other countries use different frameworks and phase names, such as the RIBA Plan of Work in the UK. The invoicing principle is the same: tie each billed amount to a defined stage of work.

How percent-complete billing works

Under percent-complete billing, each invoice reports how far through each phase the work has progressed and bills the difference between fee earned to date and fee previously billed. The calculation for each phase is:

• Fee earned to date = phase fee x percent complete.
• Amount due this period = fee earned to date - previously billed.

Repeat that for every phase, add the results, and you have the basic services portion of the invoice. The percentages are your professional judgment of progress, so be ready to explain them. Many firms base them on hours spent against budget, drawings completed or milestones reached. If the client wants more certainty, tie phase billing to defined deliverables, as described in our guide to milestone payments.

During construction administration, CA fees are often billed evenly over the expected construction duration or in line with the contractor's progress. If the construction schedule slips, the contract should say whether extended CA time is an additional service.

Sample architect progress invoice

The following is an illustrative invoice for a small commercial renovation. All figures are examples. The fee is 8% of an estimated $1,200,000 construction cost, or $96,000, split 15/20/40/5/20 across the phases. This is the fifth monthly invoice. The contract allows reimbursables at cost plus 10%, and the owner authorized additional services for a revised entry design at $150 per hour.

Phase	Phase fee	% complete	Earned to date	Previously billed	This invoice
Schematic design (15%)	$14,400.00	100%	$14,400.00	$14,400.00	$0.00
Design development (20%)	$19,200.00	100%	$19,200.00	$14,400.00	$4,800.00
Construction documents (40%)	$38,400.00	50%	$19,200.00	$0.00	$19,200.00
Procurement (5%)	$4,800.00	0%	$0.00	$0.00	$0.00
Construction administration (20%)	$19,200.00	0%	$0.00	$0.00	$0.00
Basic services total	$96,000.00		$52,800.00	$28,800.00	$24,000.00
Additional services: revised entry design, 6 hours x $150.00 (owner authorization AS-02)					$900.00
Reimbursables: plotting $310.00 + travel $84.00 = $394.00, plus 10% = $433.40					$433.40
Total due this invoice					$25,333.40

The arithmetic:

• Phase fees: $96,000 x 15% = $14,400; x 20% = $19,200; x 40% = $38,400; x 5% = $4,800; x 20% = $19,200.
• DD this period: $19,200 x 100% = $19,200 earned, less $14,400 previously billed = $4,800.
• CD this period: $38,400 x 50% = $19,200 earned, less $0 previously billed = $19,200.
• Basic services this invoice: $4,800 + $19,200 = $24,000.
• Additional services: 6 x $150 = $900.
• Reimbursables: ($310 + $84) x 1.10 = $433.40.
• Total: $24,000 + $900 + $433.40 = $25,333.40.
• Fee remaining after this invoice: $96,000 - $52,800 = $43,200.

If the construction estimate changes, a percentage-of-cost contract usually adjusts the total fee, and the next invoice recalculates every phase fee on the new basis. Note the new cost basis clearly on that invoice, because the "previously billed" column will no longer match a simple percentage of the new fee.

To produce this in our invoice generator, enter each phase's amount due, the additional service and the reimbursables as line items, and paste the phase schedule into the notes. A structured layout such as the corporate invoice template suits clients with formal approval processes.

Reimbursable expenses and additional services

Reimbursables

Reimbursable expenses are costs incurred for the project that the contract allows you to pass through. Typical examples include travel beyond a defined radius, printing and plotting, deliveries, permit and plan review fees paid on the client's behalf, professional photography, renderings and physical models. Many contracts apply a multiplier to cover administration. Bill them as a separate section, attach or offer receipts, and do not mix them with fees. Our guide on invoicing reimbursable expenses covers documentation and markup.

Additional services

Owner-requested changes after approval are the most common source of fee disputes in architecture. Additional services should be authorized in writing before you start, priced hourly or as a fixed fee, and billed in their own section with the authorization reference. The general principles in our guide to managing scope creep with change orders apply directly. Hourly additional services need clean time records; see how to invoice for hourly work for practical tips.

What to include in an architect invoice template

• Firm name, address, license number where useful, and tax ID if required.
• Client name, project name and project address.
• Contract reference, such as the agreement date or number.
• Unique invoice number, invoice date, billing period and due date.
• Fee basis: fixed sum, percentage with the current cost basis, or hourly rates.
• Phase schedule with phase fee, percent complete, earned to date, previously billed and this invoice.
• Additional services with authorization references and hours or fixed fees.
• Reimbursable expenses itemized, with any multiplier stated.
• Retainer applied, if any, and total due.
• Fee remaining, payment terms and payment instructions.

Retainers and final invoices

Many firms ask for an initial payment at signing. Some apply it to the first invoice; others hold it until the final invoice so a cushion remains in place throughout. Whichever you choose, the contract should say so and the invoice should show the retainer balance. Our guide to retainer invoices explains both approaches. The difference between progress billing and the closing bill is covered in interim vs final invoices.

Hourly contracts with a cap

Smaller projects, feasibility studies and residential additions are often billed hourly with a not-to-exceed amount. The invoice then needs two things the client will look for first: the hours and rates for the period, and the running total against the cap. A simple summary line in the notes, such as "Billed to date $18,450 of $25,000 not-to-exceed; remaining $6,550", answers the question before it is asked. Group hours by phase even on hourly contracts, because it shows whether the design is tracking to plan and gives you early warning when a phase is consuming more of the cap than expected. If the cap is likely to be reached before the work is complete, raise it with the client in writing before you exceed it, not on the invoice that does.

Common mistakes on architect invoices

• Lump-sum monthly bills. A single "services for March" line gives the client no way to judge progress. Show the phase schedule.
• Billing a phase beyond 100%. If a phase overruns, the extra time is either absorbed or billed as an additional service with authorization, not added to the phase.
• Forgetting to update the cost basis. On percentage-of-cost contracts, the fee should change when the estimate or contract sum changes, as the agreement specifies.
• Unauthorized additional services. Work done before written approval is hard to collect. Get the authorization first.
• Reimbursables without receipts. Clients and lenders often ask for backup. Keep it organized by invoice.
• Front-loading percent complete. Overstating progress early improves cash flow briefly but damages trust when later phases bill little.
• Ignoring the retainer. Losing track of how the retainer is applied leads to awkward corrections at closeout.

Working alongside the contractor's billing

During construction, the contractor submits its own payment applications, which the architect often reviews and certifies under the AIA contract family. Keep the two processes separate: your invoice covers your fee and expenses, not the contractor's work. Understanding how contractors bill, including retainage and schedules of values, helps you review their applications efficiently; our construction invoice guide explains the basics.

An architect invoice that shows the fee basis, the phase schedule and every addition in its own section reads like a progress report. Clients and lenders can approve it quickly, and when the project closes out, the final invoice holds no surprises.