By Claire Wilson, Siteline

Billing is the heartbeat of every subcontractor’s business. Yet for many companies, it’s also the source of their greatest stress. Slow payments, complex GC requirements, and compliance oversights all create challenges that ripple from the back office to the field.

According to Siteline’s State of Subcontractor Billing in 2025, subcontractors wait an average of 96 days to get paid. Meanwhile, three out of four owners are dipping into their personal savings to keep projects moving. It’s no wonder cash flow feels like a constant uphill battle.

While you can’t force the owner to release payments faster, you can tighten your own processes. These are the 10 best billing practices I’ve picked up from talking to hundreds of subs over the years.

1. Carefully review your contract’s billing and payment terms.

If you’ve ever had trouble getting paid, there’s a good chance it started in the contract. Billing language gets buried in legal jargon, so it’s easy to overlook—until it becomes a problem months down the road. Look closely for the following.

• Pay-if-paid vs. pay-when-paid: Pay-if-paid means you only get paid if the GC does—avoid it at all costs. Pay-when-paid delays timing but guarantees you’ll get paid eventually.
• Retainage terms: Standard retainage is 5-10%—push back if it’s higher. Negotiating partial or milestone releases is becoming more common, too, and it can really help your cash flow.
• Pay app requirements: Client portals, custom forms, submission schedules—all of it matters. Miss a deadline or detail, and you could be waiting another 30 days for payment.
• Lien waiver conditions: Watch for language that waives your lien rights (illegal in many states) or requires unconditional waivers before payment. Both kill your leverage on a project.

Flag questionable clauses early and come prepared with mutually agreeable alternatives. Even if the GC won’t budge, you’ll at least know what’s needed on your end to avoid disputes later.

2. Front-load your Schedule of Values.

If you only bill in large chunks tied to late-stage work, you’ll be waiting months to recover costs. Instead, structure your SOV so you can bill steadily from the start.

• Break down line items: Instead of one $100K “HVAC install,” split it into “mobilization,” “submittals,” and “equipment delivery” so you can bill earlier.
• Bill for pre-construction tasks: Shop drawings, permits, or early procurement can often be billed up front if you plan for it.
• Stay credible: GCs push back if your SOV looks inflated. Aim for balance so you can protect your cash flow without raising eyebrows.

3. Stay on top of changes.

Change orders derail more cash flow than almost anything else. Without clear controls, they can quickly become disputed costs that delay payment—or never make it onto the pay app at all.

• Don’t start without written approval: Verbal agreements are a recipe for disputes. Get signatures before work begins.
• Document everything: Back up COs with photos, field logs, and email confirmations. Paper trails matter.
• Integrate into billing immediately: Approved COs should roll into the very next pay app.
• Over-communicate: Regular check-ins with the GC help keep COs visible and prevent “we never agreed to that” arguments.

4. Standardize lien waivers.

Lien waivers are the tollbooth on the road to payment—you don’t get through without the right one. To keep things moving:

• Know the rules: Some states require statutory forms; others allow custom waivers. Signing the wrong one at the wrong time can negate your lien rights. (Check out Siteline’s lien waiver guide to steer clear of common missteps.)
• Anticipate GC requirements: Many GCs won’t release payment until every tier submits waivers. Find out if they require lower-tier waivers before billing starts.
• Build into your process: Require vendors and sub-tiers to send waivers with monthly invoices so you’re not scrambling.

5. Perfect the pay app process.

Rejected pay apps are one of the easiest problems to avoid—and one of the most damaging to your operations when they happen.

• Use the right forms and portals: AIA® G702 vs. custom GC templates, Procore vs. Textura—every GC is different. Take note of what each one requires.
• Submit complete backup: Include photos, percent-complete logs, and stored materials documentation up front.
• Track deadlines religiously: Missing a cutoff can push you back a full cycle. Keep a master calendar for all projects, or use a centralized tool that keeps track of all your billing deadlines and activity for you.

6. Closely monitor A/R aging.

Subs who stay on top of aging reports can spot money troubles before they spiral, and even use that data to adjust their approach to future work.

• Spot trends by GC: If one client consistently drags past 90 days, that’s not bad luck—it’s a pattern. Bake that risk into your pricing or reconsider future work with them.
• Track by project: A project that’s slipping financially is just as dangerous as one that’s slipping on schedule. Catch it early, and you can course-correct.
• Share with PMs: Billing visibility isn’t just for accounting. Field leaders need to see which projects are cash-positive and which ones are bleeding, so they can prioritize accordingly.

7. Create an A/R escalation plan.

“Wait and hope” isn’t much of a plan when it comes to collecting the money you’re owed. A stronger strategy? A well-documented A/R escalation plan to keep teams aligned and ensure overdue invoices don’t slip through the cracks.

• Respond immediately: Don’t wait weeks to follow up on past-due invoices. The faster you act, the more seriously the GC takes it.
• Assign clear roles: Decide who sends reminders, who calls the GC, and when to escalate to leadership. Confusion leads to inaction.
• Keep follow-ups consistent: A rhythm of weekly check-ins keeps the pressure on without making you feel like the bad guy.
• Stay united: Mixed messages from different departments weaken your position. Make sure everyone’s on the same page before reaching out.

8. Improve field-to-office collaboration.

When field and office teams aren’t in sync, cash flow takes the hit. Undocumented change orders become billing problems. Missing progress updates leave accounting guessing. Tighter collaboration prevents most of these issues before they start.

• Train PMs on billing impact: Frame billing as part of project management success. PMs should understand that controlling costs and documentation isn’t just “office work,” it directly drives whether their projects are profitable.
• Hold monthly reviews: Regular check-ins between accounting and PMs keep billing issues visible. These meetings also help PMs connect their field decisions to real-time cash flow.
• Implement accountability: PM performance should include the financial health of their projects, not just schedule and quality. If a project is losing money or payments are lagging, that should be part of the conversation.

9. Proactively manage compliance.

Compliance may not be the first thing that comes to mind when payments stall, but it causes delays more often than subcontractors realize. An expired insurance certificate or a missing safety document is all it takes for a GC to put your check on hold.

• Assign a compliance lead: Designate one person to track COIs, safety docs, bonding, and other requirements across all projects.
• Make it a shared responsibility: Clue PMs into which compliance items can freeze payment so they can act fast if a GC flags something on site.
• Use tools for tracking: A central system for deadlines and expirations (instead of scattered spreadsheets and emails) ensures everyone on the project can see compliance status and avoid last-minute surprises.

10. Forecast cash flow needs.

Cash forecasting doesn’t have to be perfect; it just has to be consistent. Subcontractors who update forecasts regularly can spot tight weeks in advance, plan around them, and avoid the scramble of chasing credit at the last minute.

• Use a rolling 12- to 13-week forecast: This window is long enough to capture payroll cycles, major material purchases, and retainage, yet short enough to adjust as projects evolve. Update it weekly to stay accurate, and involve PMs so upcoming milestones and field realities are reflected.
• Base projections on payment history: Don’t forecast from the contract—forecast from reality. If a GC routinely pays in 45 days instead of 30, plan for 45.
• Run “what-if” scenarios: Model how late payments, unapproved change orders, or other delays would impact cash so you’re ready with solutions before issues hit.

The subcontractors who stay ahead of payment problems are the ones who anticipate issues and put strong billing systems in place. By weaving these best practices into your operations, you can cut down on avoidable delays, protect your leverage, and give your team more predictability.

About the author: 

Claire Wilson is the co-founder and COO of Siteline, a billing software for subcontractors. Previously, she was a project manager at Tishman Construction in New York City, where she worked on major projects like Hudson Yards and JP Morgan’s Corporate Headquarters. She is an active CFMA San Francisco member, serves on the Bay Area Subcontractors Association board, and has spoken at numerous regional and national construction conferences. Claire holds a BS in Civil Engineering from Bucknell University.