How to Calculate the True Cost of Winning a New Project for Your Architecture Firm

Search “how to calculate customer acquisition cost” and you’ll find dozens of guides. They’ll all give you the same formula: total sales and marketing spend divided by number of new customers. They’ll all use a SaaS example with ad budgets, SDR teams, and free trial conversions.

None of them will help you if you run an architecture firm.

This guide walks through exactly how to calculate your real CAC as an architecture practice, step by step, with the inputs that actually apply to your business.

Why the Standard CAC Formula Doesn’t Work for Architecture Firms

The SaaS CAC formula is simple: total sales and marketing spend divided by new customers acquired. It works for SaaS because SaaS companies have dedicated marketing budgets, structured sales teams, and clean attribution. An architecture firm’s project acquisition process looks nothing like that.

Three things make architecture firm CAC fundamentally different.

First, founder-led sales. Most architecture firms under $5M don’t have a dedicated business development team. The principal or managing partner is the rainmaker. Their time – on client meetings, RFP responses, interviews, presentations, networking at industry events – is the single largest acquisition cost. But it never shows up as “sales spend” in the P&L because the founder doesn’t invoice themselves.

Second, long relationship-based sales cycles. A conversation with a developer at a civic event might lead to an RFP six months later. A past client might call about a new project two years after the last one wrapped. There’s no clean “campaign spend” to attribute. The costs are diffused across months of relationship building, follow-ups, and conversations that don’t have a line item.

Third, team involvement in pitches. Architects develop schematic concepts for proposals. Project architects prepare fee proposals and project approach narratives. Junior staff produce presentation drawings, renderings, and portfolio materials. These are billable people doing unbillable work – a real cost that the SaaS formula doesn’t account for because SaaS companies don’t ask their engineers to create presentation boards for an interview.

But there’s a fourth difference that matters even more, and almost nobody talks about it.

Architecture firm margins are fundamentally different from SaaS margins. A SaaS company operates at 80-90% gross margin – meaning they keep 80-90 cents of every dollar after delivery costs. When they calculate how much a customer is worth over their entire relationship (known as lifetime value, or LTV), revenue and gross profit are nearly the same number. So a client paying $1,000/month for 3 years has an LTV of roughly $36,000 – and almost all of that is profit.

Architecture firms don’t work that way. A practice keeps 50-60% of fee revenue after paying the people and costs to deliver the work (known as gross profit margin, or GPM) on a good day. That means 40-50 cents of every fee dollar goes straight to delivery costs – architect salaries, subconsultant fees (structural, MEP, landscape, civil), drafting and BIM software, and project-specific expenses like printing, models, and travel. A project with $300,000 in fees generates $150,000-$180,000 in gross profit. That’s your real LTV – not the revenue number.

This is why SaaS CAC benchmarks are dangerously misleading for architecture firms. When a SaaS guide says “a 3:1 LTV:CAC ratio is healthy,” they’re talking about a business where LTV is basically revenue. For an architecture firm, a 3:1 ratio on gross profit means your acquisition cost is eating a third of the profit from every client. That’s tight. That’s why architecture firms need to target 5:1 or above – and why getting your CAC right matters more, not less, than it does for a software company.

The Architecture Firm CAC Formula

Here’s the formula, built for how architecture firms actually win work:

Three cost categories. One number. Let’s walk through each.

Principal/partner business development time. This is usually 50-70% of total CAC for firms under $5M. It includes every hour the principal spends on activities that exist to win new work – client meetings, RFP strategy, shortlist interviews, networking at AIA events and developer mixers, presentations to selection committees, relationship maintenance with past clients and referral sources.

Direct sales and marketing spend. Everything you pay for that exists to bring in new business. Website hosting and maintenance, CRM or pursuit tracking tools, industry association memberships, conference attendance, award submissions, portfolio and qualifications package production, PR or communications support, and any content creation that positions the firm. If you hire a marketing coordinator or outsource proposal graphics, those costs go here.

Team time on pursuits. Billable team members doing unbillable work. Architects developing schematic concepts for proposals. Project architects writing project approach narratives and preparing fee proposals. Junior staff producing presentation boards, renderings, and portfolio updates. Calculate their cost the same way you’d calculate founder time: hourly rate times hours spent.

Step-by-Step Calculation

Here’s the full walkthrough using a $2M architecture practice as the example. Follow along with your own numbers.

Step 1: Calculate your principal business development cost.

Find your hourly rate. Total annual compensation (salary, benefits, super/401K – what you actually cost the firm) divided by 2,080 working hours.

Estimate your weekly BD hours. Be honest. Include client development meetings, RFP reviews, shortlist interview prep, AIA chapter events, developer networking, proposal strategy sessions, past-client relationship calls, and community involvement that positions the firm. If you’re not sure, track it for one week. Most principals land between 10-20 hours per week and are surprised it’s that high.

Multiply. Weekly hours x hourly rate x 48 working weeks (accounting for holidays) = annual founder sales cost.

Example: $200K total comp / 2,080 = $96/hour. 15 hours/week x $96 x 48 weeks = $69,120/year in principal time on business development.

That’s $69K in acquisition cost before a single dollar of marketing spend. This is the number that shocks most firm principals. You can’t see it on your P&L, but it’s real – every hour you spend pursuing work is an hour you’re not spending on active projects, and your compensation doesn’t change based on how you spend your time.

Step 2: Add your direct sales and marketing spend.

Pull these from your P&L or accounting software for the same 12-month period:

• Paid advertising: Google Ads, LinkedIn Ads, Meta/Facebook, PPC, sponsored posts, any paid media
• Tools and subscriptions: CRM (HubSpot, Salesforce, etc.), proposal software, email marketing platforms, SEO tools, LinkedIn Premium
• Content and creative: Freelance writers, video production, photography, case study design – anything produced to attract or convert prospects
• Website: Hosting, maintenance, redesigns done to support lead generation
• Events: Conference tickets, sponsorships, speaking engagement travel, networking event costs, industry association memberships
• Collateral: Pitch decks, capability statements, portfolio materials created to win new work

Example: $25,000/year across all categories.

Most firms undercount this because the expenses are scattered across different P&L categories. A $500/month CRM subscription doesn’t feel like “acquisition spend” until you realise it exists entirely to manage your pipeline.

Step 3: Estimate team time on pitches and proposals.

Identify everyone beyond the founder who participates in business development. Designers creating spec work or pitch visuals. Strategists joining chemistry meetings. Project managers scoping and pricing proposals. Account managers on trial calls with prospects.

Calculate their hourly cost the same way: salary plus benefits divided by 2,080 hours. Estimate monthly hours each person spends on new business activities. Multiply by 12.

Example: Two team members averaging 8 hours/month each on business development. Their blended hourly cost is $55/hour. That’s 192 hours x $55 = $10,560/year.

This number is often smaller than founder time, but it adds up – especially if your firm does detailed custom proposals for every pursuit. If your team spends 80 hours preparing for a design competition that doesn’t result in a commission, that’s $4,400 in delivery capacity you didn’t bill for.

Step 4: Add it all up and divide.

Not “basically zero.” And for most architecture firms, principal time represents roughly two-thirds of the total. That’s the hidden cost that every SaaS-focused CAC guide completely misses.

Now Make It Useful: CAC by Channel

Your overall CAC is the starting point. The real value comes from breaking it down by how clients actually found you.

For each channel, estimate the costs specific to that channel and divide by clients won through it:

Referrals. Founder time on referral conversations and relationship maintenance, divided by clients won via referral. This is usually your lowest-cost channel – but it’s not zero. If you spent 5 hours of founder time per referral client on calls, meetings, and proposals, that’s roughly $480 per client in founder time alone. Add a portion of your CRM and tools cost.

Inbound (content and SEO). Content creation costs plus SEO tools plus a share of website spend, divided by clients won through inbound. Higher upfront investment, but the cost per client typically decreases over time as content compounds.

Outbound (ads and cold outreach). Ad spend plus outreach tools plus time on outbound activities, divided by clients won through outbound. Usually the highest cost per client, but potentially the most scalable and the least dependent on the founder’s personal network.

Events and networking. Conference costs plus sponsorships plus founder time at events, divided by clients won from those events. Often the hardest channel to attribute, but worth estimating.

When you see CAC by channel, you can answer a question most founders guess at: where should I invest my next growth dollar? The answer isn’t always “the lowest CAC channel.” It’s the channel with the best LTV:CAC ratio – because some channels produce clients who stay longer, expand scope, and generate more lifetime gross profit than others.

What Your CAC Number Actually Means

Your CAC alone doesn’t tell you if it’s good or bad. You need to compare it to what each client is worth – and for architecture firms, that means calculating the value with gross profit, not fee revenue.

Architecture firm LTV formula: Average monthly revenue per client x average client lifespan in months x GPM = Lifetime Value.

A client who commissions two projects averaging $250K in fees, at 55% GPM: $250,000 x 2 x 0.55 = $275,000 LTV. Against a $13,250 CAC, that’s a 20.8:1 ratio. Excellent.

A one-off project at $150K in fees at 40% GPM: $150,000 x 1 x 0.40 = $60,000 LTV. Against $13,250 CAC, that’s 4.5:1. Workable, but not a lot of room for error – and it highlights why repeat client relationships are so valuable to the economics of a practice.

This is why GPM matters so much. Improving your delivery margins doesn’t just put more money in your pocket month to month – it fundamentally improves your growth economics by increasing LTV on every client you’ve already won.

Here’s what healthy looks like at each stage:

These benchmarks reflect patterns across professional services firms. Your numbers will vary based on service mix, pricing model, and client type. Use as directional guideposts, not rigid targets.

Below 3:1 means growth is too expensive – you need to either reduce CAC or improve retention and margins to push LTV up. Between 3:1 and 5:1 is workable but tight. Above 5:1 means your growth economics are healthy and you can invest more confidently in scaling. The Financial Performance Check can help you benchmark where you sit.

What to Do Monday Morning

Track your time for one week. Keep a rough log on your phone. How many hours did you spend on activities that exist solely to win new business? Multiply by your hourly rate. That’s your weekly founder CAC contribution – and it’s probably the number that surprises you most.

Pull your P&L and tag every sales and marketing expense. CRM subscriptions, media spend, event tickets, content costs, proposal software. Add it up for the last 12 months. Most founders haven’t seen this number as a single total before.

Count your new clients from the past 12 months. Divide your total acquisition costs by that number. Write it down. That’s your CAC – and now every growth decision you make has a baseline to measure against.

The firms that grow efficiently aren’t the ones that spend the most on acquisition. They’re the ones that know exactly what they spend, know what each client is worth, and can see whether the ratio between those two numbers supports the growth they’re planning.

The reason most architecture firm principals have never calculated their CAC isn’t that the math is hard. It’s that nobody has shown them the version of the math that applies to their business. Every guide uses SaaS examples with subscription funnels and 85% margins. That’s a different world.

Your firm wins projects through relationships, referrals, proposals, and founder hustle. The costs are real – they just don’t look like a SaaS acquisition budget. And because your margins are tighter, every dollar of CAC matters more. Once you see the numbers clearly, every growth decision gets sharper.