Construction companies need working capital because they pay for materials, labor and equipment weeks before progress payments arrive — and part of every payment is often held back as retainage until the job is done. Pay-when-paid clauses and change-order disputes stretch the gap further, and sureties size your bonding capacity partly on working capital.
The cash gap on a commercial project
Subcontract on a commercial build (illustrative)
- Day 0− Materials and equipment rental
- Day 14− Crew payroll (and every 2 weeks after)
- Day 30− Second payroll and overhead while the pay app is reviewed
- Day 65+ Progress payment, minus 10% retainage
- Day 180+ Retainage released after completion
Retainage in numbers (illustrative)
A $100,000 progress billing with 10% retainage
- Work billed this period$100,000
- Paid now (after retainage)$90,000
- Held as retainage until completion$10,000
Why do contractors run short of cash?
Retainage
A slice of every payment held until the end of the job.
Progress billing cycles
Monthly pay apps, then approval and payment delays.
Pay-when-paid clauses
Subs wait until the GC is paid by the owner.
Materials up front
Long-lead items and price escalation.
Payroll and equipment
Crews and rentals billed weekly or biweekly.
Bonding capacity
Sureties weigh working capital when sizing bonds.
How much working capital does a contractor need?
Retainage is the number most contractors underestimate, because it is invisible in the monthly cash flow until the job ends.
| Illustrative: $500,000 contract, 10% retainage | Amount |
|---|---|
| Billed over the job | $500,000 |
| Held back as retainage | $50,000 |
| Released | after completion and final approval |
| Cash unavailable while you are still paying crews | $50,000 |
Stack three jobs at that size and $150,000 is sitting in retainage while payroll, materials and equipment rental keep running. That is also why sureties ask for working capital: bonding capacity is a judgment about whether you can carry the gap between billing and collection, not just about your backlog.
Funding options for contractors
| Option | Fits which gap | Speed | Cost | Watch out |
|---|---|---|---|---|
| Business line of credit | Payroll and materials between pay apps | Days–weeks | Low–medium | Covenants tied to WIP |
| Construction invoice factoring | Approved pay apps | Days | Medium | Retainage usually not advanced |
| Supplier credit / joint checks | Materials | Immediate once approved | Low | Lien waiver paperwork |
| Equipment financing | Machines and vehicles | Days | Low–medium | Collateral |
| SBA 7(a) / CAPLines (contract) | Contract-specific working capital | Weeks–months | Low | Time, documentation |
| Merchant cash advance | Emergency only | 1–3 days | High | Daily debits vs. 60-day pay cycles — see MCA default |
Why banks often say no to contractors
| Bank concern | What helps |
|---|---|
| Lumpy, project-based revenue | A current WIP schedule and backlog report |
| Underbilling and fade | Job-cost accounting reviewed by a construction CPA |
| Retainage and slow GCs | AR aging by customer, with retainage shown separately |
| Bonding and claims history | Surety letters and clean claims record |
Carrying advances already? See MCA consolidation lenders or MCA debt restructuring.
Frequently asked questions
What are construction companies’ working capital needs?
Contractors fund materials, payroll and equipment for weeks before a progress payment arrives, and a portion of each payment — retainage — is often held until the project is complete. Pay-when-paid clauses can push subcontractor payments back further.
What is retainage in construction?
Retainage is a percentage of each progress payment that the owner or general contractor withholds until the work is finished and accepted. It is commonly around 5–10%, set by the contract and, on some public projects, by law.
How do I calculate WIP in construction?
A work-in-progress (WIP) schedule compares, for each job, the costs incurred and estimated percentage complete with what you have billed. Billing more than the work completed is overbilling; billing less is underbilling, which ties up your cash. Lenders and sureties review WIP schedules closely.
Why does working capital matter for bonding?
Surety companies look at a contractor’s working capital and net worth when setting bonding capacity. Stronger working capital usually supports larger bonded projects.