HOW MUCH WORKING CAPITAL DOES YOUR BUSINESS ACTUALLY NEED?
QUICK ANSWER
Working capital is current assets minus current liabilities. For a commercial subcontractor, it determines whether you can mobilize the next job without borrowing, survive a 60-day payment delay, and carry overhead through a slow month. Most owners don't know their actual working capital position — and most who do know it are below where they need to be. The SPM target is $1.2M for a stabilized $5M to $8M subcontractor, with $650K as the non-negotiable cash floor.
$1.2M WORKING CAPITAL. $650K CASH FLOOR. HERE IS HOW YOU GET THERE.
BY JOSH LUEBKERPublished: June 2026Updated: June 2026
The Working Capital Formula for Subcontractors
Working capital is not a fixed number — it scales with revenue and with how long your cash cycle runs. A $2M subcontractor and an $8M subcontractor have different requirements because the jobs are bigger, the mobilization costs are higher, and the payment cycle covers more dollars.
THE MINIMUM FLOOR: 3 MONTHS OF OVERHEADThe baseline working capital requirement for any commercial subcontractor is enough cash to cover 3 months of overhead if revenue stopped tomorrow. On $800K in annual overhead, that is $200K minimum. Most subcontractors are below this. They are funding overhead with their line of credit in slow months rather than maintaining the reserve.
THE MOBILIZATION RESERVE: 10% OF BACKLOGEvery project requires mobilization capital before the first invoice is paid. On a $600K project, mobilization typically runs $40K to $80K — equipment, materials, labor, insurance — before any cash comes in. With 3 to 5 concurrent projects in various stages, the aggregate mobilization reserve should be approximately 10% of active backlog.
THE PAYMENT CYCLE BUFFER: 1.5X MONTHLY REVENUEIf your average payment cycle is 45 days, you are carrying 1.5 months of revenue in receivables at any given time. Your working capital needs to absorb that float without drawing on credit. On $5M in annual revenue, 1.5 months is $625K in receivables that need to be funded.
SPM Working Capital Targets by Revenue Level
$250K
Target at $1–2M Revenue
$500K
Target at $2–4M Revenue
$1.2M
Target at $5–8M Revenue
$2M+
Target at $8–12M Revenue
Why Most Subcontractors Are Below Target
OWNER DRAWS ABOVE NET PROFITThe most common working capital drain. The business makes $180K in net profit. The owner draws $280K. The $100K gap comes from working capital. Year after year, the business grows in revenue but working capital doesn't build because profits are being extracted faster than they accumulate.
EQUIPMENT PURCHASES FUNDED FROM OPERATING CASHA $90K equipment purchase funded from the operating account reduces working capital by $90K immediately. The asset is on the balance sheet. The cash is gone. Equipment should be financed with structured debt — not with the same cash that needs to fund payroll next Friday.
AP PAID BEFORE AR IS COLLECTEDMost subcontractors pay AP faster than they collect AR. Vendors get paid in 30 days. GCs pay in 45 to 60. The spread means the business is constantly funding its vendors from its own working capital rather than from collected receivables.
REACTIVE DEBT ACCUMULATIONAn MCA to make payroll. A quick LOC draw for a material deposit. A vendor financing arrangement for equipment. Each reactive borrowing reduces working capital through interest and fees. Over 2 to 3 years of reactive borrowing, a $3M subcontractor can have $150K to $300K in annual debt service draining the same pool it needs for working capital.
Frequently Asked Questions
Cash is a component of working capital. Working capital is current assets — cash plus receivables plus prepaid expenses plus inventory — minus current liabilities — AP, accrued payroll, short-term debt. A company can have $200K in cash but negative working capital if its short-term liabilities exceed its current assets. The current ratio (current assets divided by current liabilities) is the more useful metric for sureties and banks.
Below 1.5x, bonding capacity compresses and bank credit tightens. Most surety underwriters want to see at least 1.5x before extending meaningful aggregate bonding. Banks use the same threshold for construction line of credit approval. Getting above 1.5x and maintaining it is what keeps those doors open as revenue grows.
From negative working capital, it typically takes 12 to 24 months depending on how fast profit can be generated and retained. CFOS accelerates the build by eliminating reactive debt first (stopping the bleed), then correcting billing lag (pulling cash forward), then structuring owner draws to match net profit rather than exceed it. The sequence matters as much as the targets.
DO YOU KNOW YOUR ACTUAL WORKING CAPITAL POSITION?
Most owners know the bank balance. Few know current assets minus current liabilities. First call calculates the real number and shows you the gap.
Former commercial construction project manager and master electrician. Managed 150+ projects totaling $300M+ including Google data centers, military bases, hospitals, and high-rises. Now fractional CFO for commercial subcontractors doing $1M–$12M through Sulphur Prairie Management.
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