In this article
Calculate contractor customer acquisition cost from your own ledger and customer records, not a national average. Add the sales and marketing expense used to win a defined group of customers, divide by the deduplicated new customers in that cohort, and compare the result with collected first-job gross profit.
Disclosure: theBuildd publishes this guide and sells residential home-improvement leads. We benefit if a reader considers our service. Results are not guaranteed, and no theBuildd customer outcome is used as a benchmark here. Research sources were checked on September 26, 2026.
Contractor customer acquisition cost starts where lead cost stops
Customer acquisition cost, usually shortened to CAC, answers a later and broader question than cost per lead. It asks what the business spent to gain a new customer, not what it paid for a call, form, opt-in, estimate, or accepted job.
| Metric | Numerator | Denominator | Decision it supports |
|---|---|---|---|
| Cost per lead | Source or campaign spend | Recorded leads | Is the top-of-funnel unit getting more expensive? |
| Cost per qualified lead | Attributable source cost | Leads passing one written qualification rule | Is the source producing opportunities the estimator can work? |
| Cost per booked job | Source spend | Accepted jobs attributed to the source | What did accepted work cost at the channel level? |
| Customer acquisition cost | Total attributable sales and marketing acquisition expense | Deduplicated new customers | Can the business afford to gain customers this way? |
The distinctions matter because one household can submit two forms, schedule an estimate, accept two jobs, and still be one new customer. A lead report can count several events where finance should count one customer.
Use the contractor lead-cost guide for provider and channel pricing, the qualified-lead cost method for the screening stage, and the cost-per-booked-job framework for accepted work. This page owns the customer-level calculation after those stages.
Use one formula and publish the input policy
The arithmetic is simple:
Contractor CAC = total attributable sales and marketing acquisition expense ÷ deduplicated new customers acquired
The policy behind each input determines whether the number is useful. Put four definitions beside every CAC report:
- Cost list: which expenses enter the numerator and how shared costs are allocated.
- Customer-recognition event: the point at which a prospect becomes a new customer.
- Scope and attribution: blended business total, named channel, trade, territory, or job type.
- Maturity window: how long a source cohort remains open before the result is treated as final.
For residential contractors, a signed proposal can be a useful operating event. A received deposit or first collected payment can be a stronger cash event. Track both if the sales cycle is long, but do not change between them when a channel looks weak.
A clean label might read: “Rolling-quarter blended CAC; includes the written acquisition-cost list; new customer recognized at first collected payment; source cohorts mature for 90 days.” The exact policy can differ by business. The requirement is consistency and reconciliation to finance.
Build the numerator from every cost of winning the customer
Counting only the ad invoice produces media CAC, not full contractor CAC. The complete numerator includes the work required to attract, answer, sell, and convert a new customer when those costs are attributable to acquisition.
| Cost category | Include when | Allocation rule to record |
|---|---|---|
| Lead fees and paid media | Used to produce new-customer opportunities | Actual invoiced spend less monetary credits |
| Agency and management fees | The work manages acquisition channels | Direct fee or consistent share of a broader retainer |
| Website, landing page, and creative work | Built or maintained for acquisition | Expense in period or an agreed amortization policy |
| Call tracking, CRM, and acquisition software | Used to capture, route, or attribute prospects | Direct subscription or consistent acquisition share |
| Intake and sales payroll | Staff time is used to answer, qualify, estimate, and close new work | Recorded hours or a stable percentage of loaded payroll |
| Sales commission and referral incentive | Triggered by a new customer | Actual amount tied to the cohort |
| General overhead | It directly supports acquisition and management chooses to allocate it | Written method applied across all periods and sources |
Do not put direct job labor, materials, permits, equipment, or subcontractor cost into CAC. Those are costs of delivering the work. Subtract them from collected job revenue to calculate gross profit, then ask how much of that gross profit acquisition consumed.
Avoid selective allocation. Adding call-center labor to one lead provider while ignoring the same labor for search ads manufactures a winner. The same rule applies to contractor marketing channels, referrals, marketplaces, and lead sellers.
If an expense serves both existing and new customers, allocate only the acquisition portion. An office coordinator who spends 30% of documented time on new inquiries and 70% on existing work should not have 100% of loaded payroll assigned to CAC. Use time records when possible; otherwise choose a conservative policy and keep it unchanged.
Count a new customer once and let the cohort mature
The denominator should contain people or customer accounts, not marketing events. Deduplicate by customer record, address, phone, and email under a documented process. Then remove returning customers unless the report is explicitly measuring reactivation.
Choose the recognition event before looking at channel results:
- Accepted-contract CAC is useful for operating decisions but includes work that may cancel or never collect.
- Deposit-received CAC moves closer to cash and can fit project contractors that collect before production.
- First-completed-job CAC fits service businesses that collect at completion.
- First-collected-payment CAC is conservative and finance-friendly, but arrives later.
Keep the earlier events in the funnel even if collected payment is the official denominator. A rising gap between accepted contracts and collected customers can reveal cancellation, financing, scheduling, or collections problems that a single final number hides.
Time matters as much as customer identity. March spend can produce April estimates and May deposits. Dividing March expense by customers who happened to pay in March mixes different cohorts.
Tag the original acquisition cohort, then follow it through a maturity window suited to the sales cycle. A service-call cohort may mature quickly. A remodeling cohort may need much longer. Keep open estimates visible as pending; do not assign them assumed future customers or revenue.
Blended CAC is less sensitive to imperfect attribution because it includes all acquisition cost and all new customers. Channel CAC is more diagnostic, but it needs a declared attribution rule. Original source, last touch, and multi-touch models can credit the same journey differently. Pick one operating model and do not silently switch it between sources.
The published construction CAC benchmark does not fit residential contractors
No inspected source established a representative customer acquisition cost benchmark for US residential contractors by trade. Several pages publish a “construction” number, but the population and calculation method do not answer this article’s question.
First Page Sage’s current B2B CAC report publishes a combined construction figure of $281. Its own method says the data comes from agency clients between January 2022 and August 2025. Organic data is weighted toward SEO, inorganic data toward PPC and paid social, and the combined result uses a 75% organic and 25% inorganic weighting chosen to reflect the firm’s services.
The report also excludes email, events, direct mail, outdoor advertising, and other channels for insufficient data. It is explicitly a B2B report. Those limitations make $281 a description of that publisher’s selected construction dataset, not a residential roofing, HVAC, plumbing, painting, solar, or remodeling benchmark.
Siana’s construction CAC page repeats the same construction values and says its channel estimates were scaled from public benchmarks to reflect relative cost, effort, and conversion efficiency. Without raw customers, costs, trade mix, or allocation rules, those channel values are modeled estimates rather than an independent contractor sample.
Two current contractor guides reach the more defensible conclusion. 99 Calls says there is no single CAC benchmark for every home-service company. PipelineOn’s HVAC guide says a national average cannot decide the acceptable cost for a particular repair or replacement business. Both are vendor-authored pages, so they support the observed editorial pattern, not a neutral market average.
| Published evidence | What it can support | What it cannot support |
|---|---|---|
| B2B agency client CAC | Directional context for that sample and channel mix | Residential contractor target by trade |
| Scaled channel estimate | A publisher’s model | Observed customer acquisition cost |
| Lead-cost benchmark | Media or lead-price context | Full CAC without new-customer and sales-cost data |
| Contractor’s mature cohort | That business’s cost under a documented policy | A universal national average |
The honest benchmark is your own comparable history: same trade, job type, territory, channel scope, cost policy, customer event, and maturity window. External figures can prompt questions. They cannot replace those inputs.
Calculate blended and channel CAC from one worksheet
Start with a blended report that finance can reconcile. Then create channel and job-type views without changing the total.
| Worksheet field | Source of truth | Control |
|---|---|---|
| Reporting and cohort dates | CRM and accounting period | State both dates clearly |
| Lead/media/provider spend | Vendor invoices and ad accounts | Use actual spend, not budget limit |
| Management, tools, and creative | General ledger | Apply written allocation policy |
| Intake and sales labor | Payroll, commission, time records | Use loaded cost and acquisition share |
| New-customer count | CRM plus invoicing/payment system | Deduplicate and remove returning customers |
| First-job collected revenue | Accounting/job system | Include the same customer cohort |
| Direct job cost | Job costing | Same jobs and period as revenue |
| Gross profit | Collected revenue minus direct job cost | Do not substitute quoted revenue |
Here is a hypothetical 90-day contractor cohort. Every number is illustrative, not an industry benchmark or expected result.
| Acquisition input | Illustrative amount |
|---|---|
| Lead-provider and advertising spend | $11,400 |
| Agency and management fees | $3,100 |
| Tracking and acquisition software | $650 |
| Creative and landing-page allocation | $1,350 |
| Allocated intake and sales labor | $7,200 |
| Referral incentives | $1,100 |
| Total acquisition expense | $24,800 |
Assume the cohort produces 40 deduplicated new customers at the selected recognition event.
Blended CAC = $24,800 ÷ 40 = $620 per new customer
Check the result by multiplication:
40 customers × $620 CAC = $24,800 total acquisition expense
If the report displays a different reconstructed total, a cost, customer, or rounding rule changed. Fix the source records before using the number.
For channel CAC, add the channel’s direct cost and its consistent allocation of shared acquisition costs, then divide by new customers attributed under the declared model. Keep the blended total beside the channel rows. Channel results that do not reconcile to the blended report need an unallocated-cost row or a corrected attribution map.
Set the ceiling from first-job gross profit and cash timing
A good CAC is not the lowest number in a benchmark table. It is a cost the business can pay while leaving enough contribution, capacity, and cash to perform the work.
Start conservatively with the first job:
First-job gross profit per new customer = collected first-job revenue minus direct job cost, divided by new customers
Then set the ceiling:
Maximum CAC = first-job gross profit per new customer minus required contribution after acquisition
Continue the hypothetical cohort. Assume its first jobs produce $96,000 of collected revenue and $56,000 of direct job cost. The cohort’s gross profit is $40,000.
First-job gross profit per new customer = $40,000 ÷ 40 = $1,000
With a $620 CAC, acquisition consumes 62% of first-job gross profit and leaves $380 per new customer before the remaining overhead, tax, financing, warranty, and profit requirements.
$620 CAC ÷ $1,000 first-job gross profit = 62%
$1,000 first-job gross profit - $620 CAC = $380 remaining contribution
Those results do not say $620 is good or 62% is acceptable. Management must decide how much first-job contribution the business needs. If the required amount were $650 in this illustration, maximum CAC would be $350, not $620.
Repeat work can support a higher acquisition cost, but only after actual customer cohorts establish retention, repeat frequency, gross profit, and cash timing. Do not rescue a weak first-job result with an assumed lifetime value copied from another contractor.
Capacity is another ceiling. Affordable acquisition can still be wasteful when estimators cannot run appointments or crews cannot complete sold work. Review CAC with backlog, estimate capacity, production capacity, and cash required before the next collection.
Segment CAC by trade and job type without inventing averages
“Contractor CAC” can hide more than it explains. Calculate the blended result for finance, then segment the same records far enough to expose different economics.
| Segment | Why it belongs in the report |
|---|---|
| Trade | Roofing, HVAC, plumbing, remodeling, painting, solar, and other work have different sales and production cycles |
| Job type | Service, repair, replacement, maintenance, and remodeling can carry different gross profit and repeat behavior |
| Territory | Travel, competition, crew density, and channel availability differ by service area |
| Channel | Paid search, profiles, referrals, lead providers, and owned search have different cost structures |
| New versus returning | Returning customers do not belong in new-customer CAC |
| First job versus repeat work | Separates observed first-job economics from later value |
Do not publish a trade CAC when the segment has too few mature customers to be useful. Show cost, customer count, pending outcomes, and the policy instead of a precise-looking average built from one or two wins.
The purpose of segmentation is diagnosis. If blended CAC rises, the detail should show whether price, conversion, job mix, territory, labor allocation, or attribution changed. It is not a reason to create a benchmark where the evidence is thin.
Run theBuildd pricing through the same customer denominator
theBuildd’s current Lead Generation plan costs $3,000 per month, or $2,500 with LAUNCH25. It publishes 10–15 exclusive leads per week for that monthly plan. Lead volume is not customer volume, so neither figure establishes CAC.
There is one buyer per lead through theBuildd, while the homeowner may still seek other quotes independently. Delivery is by text and email within 10 minutes. Your team makes the qualifying call. Leads meeting the replacement criteria are replaced rather than refunded. The agreement is month to month, with 10 days’ written notice before the next billing date, and coverage is agreed by residential trade and ZIP code.
Use actual invoice and labor data:
theBuildd CAC = (actual plan fee + allocated intake and sales expense + other attributable acquisition cost) ÷ new customers from the matured cohort
Do not subtract a replacement as a cash credit. The provider’s fee remains in the numerator; the replacement lead enters the same source cohort and follows the normal customer path.
The one-time $200 trial delivers 4–7 exclusive leads. It can test delivery, territory fit, and your intake process. It is too small to establish a universal customer acquisition benchmark, and no number of delivered leads promises a customer.
Review current pricing and plan limitations before modeling the invoice. Then check trade and ZIP fit if the calculation works under your own allowable CAC. theBuildd is a poor fit when you require commercial projects, outsourced qualification, a promised number of customers, or a guaranteed return.
Use CAC to choose the next constraint to fix
CAC is a decision metric, not a verdict on marketing alone. When it rises, locate the change before cutting or increasing spend.
- If acquisition expense rose while new-customer conversion held, inspect media prices, provider fees, management cost, and labor allocation.
- If lead cost held while CAC rose, inspect reach, qualification, estimating, follow-up, financing, cancellation, and collection.
- If CAC held while first-job contribution fell, inspect job mix, pricing, direct cost, callbacks, and discounting.
- If one channel looks unusually cheap, verify that shared costs and organic or referral customers were not assigned to the wrong denominator.
- If results swing by month, lengthen the maturity window or use a rolling view without changing the policy.
- If CAC is affordable but backlog is growing, constrain volume until estimating and production capacity recover.
Calculate the number, publish the rules beside it, and keep the underlying cohort open long enough to mature. That creates a contractor benchmark worth using: your own audited cost to gain a new customer, tied to the gross profit and cash that customer actually produced.