How much should I bill on my first pay app to avoid going upside down?

If you're a subcontractor asking "how much should I bill on pay app 1?" — the honest answer is: enough to cover every dollar you've spent before the check arrives, plus the cost of financing that spend at your working capital rate.

Most subs start a job, front the mobilization, and figure out the cash math later. That's how jobs quietly eat working capital for 45 to 60 days before Pay App 1 even hits the bank. By the time App 2 rolls around, you're already three weeks behind, floating labor, and trying not to miss a payroll.

This free calculator runs the math in 30 seconds. Plug in your total project cost, how much you'll spend before App 1 gets paid, how many days until you actually see the check, and your working capital rate. It spits back the minimum you need to bill on App 1 to break even on the float — so you stop subsidizing the GC's job with your own cash.

Project Mobilization Calculator | SPM – The Construction CFO
Free Tool — SPM The Construction CFO

How much do you need
to bill on Pay App 1?

Most subs start a job and figure out the cash later. This calculator tells you exactly how much you need to recover on your first pay application to fund the project without going upside down before App 2 hits.

Project Inputs
$
Your total projected cost to complete — labor, materials, equipment, subs.
%
Your line of credit rate, or cost of capital if self-funding.
Cost Timing — Before First Payment
From mobilization to cash in hand. Include billing cutoff + payment terms.
%
How much of the job cost do you expect to spend before your first check arrives?
You're floating in project costs before your first dollar arrives. At your working capital rate, that's /day in financing cost. Make sure your App 1 billing covers it.
Cost Floated Before App 1
—
What you'll spend before you see a dollar
Daily Financing Cost
—
Per day on the floated amount
Financing Cost to Recover
—
Interest/capital cost for the float period
Minimum App 1 Billing
—
Cost floated + financing to recover
App 1 Breakdown
Costs incurred before payment —
Financing cost (— days × daily rate) —
Minimum App 1 billing needed —

How this works: Before your first pay app check arrives, you've already spent money on labor, materials, and mobilization. That money has to come from somewhere — your line of credit, your cash reserves, or your own pocket. This calculator figures out how much of your total budget you'll spend in that window, adds the cost of financing it at your working capital rate, and tells you the minimum you need to bill on App 1 just to break even on the float. Bill less than that and you're subsidizing the GC's job with your own money.

Want to see this across the whole job?

A 13-week cash flow forecast shows you every week where you're exposed — before it happens. Starting at $69.

Get Your Forecast →
SPM — The Construction CFO for Subcontractors  |  constructioncfo.net  |  This calculator is for estimating purposes only and does not constitute financial advice. Actual financing costs will vary based on your specific capital structure and project cash flow timing.

Why do subcontractors always run out of cash in the first month of a job?

Because the job has a float period — the gap between when you start spending money on labor, materials, and mobilization and when the first pay app check actually clears your bank. That gap is typically 30 to 60 days. During that window, every dollar you spend is coming out of your working capital, not the project. If you didn't bid that float into App 1, you're personally financing the GC's job.

What does "going upside down" mean on a construction job?

You're upside down when your costs-to-date on a job exceed the cash you've collected on that same job. For a sub running multiple projects, going upside down on one means pulling cash from another to keep it alive. That's the fast track to cash flow chaos, AP piling up, and pay-when-paid turning into can't-pay-anyone.

How do I calculate mobilization costs for a subcontractor bid?

Start with everything you spend before App 1 gets paid: mobilization labor, initial materials, equipment delivery, bond premiums, insurance, site-specific safety, and your own overhead allocation. Add the cost of financing that spend for the full float period (days until App 1 payment × your working capital daily rate). The calculator above does this automatically.

Is mobilization billable on pay app 1?

Usually yes, but only if it's called out in the schedule of values. Many GCs push back on front-loading, but a properly structured mobilization line item (often 3 to 7 percent of contract value) is standard and defensible. If the GC won't let you bill mobilization separately, you need to load it into your first few SOV line items instead.

How much should I front-load my schedule of values?

Enough to cover mobilization + the financing cost of the float period, but not so much that it looks abusive. A good rule of thumb: if your calculator output is 8 to 12 percent of total contract value, you can usually spread that across the first two or three line items of the SOV without triggering GC pushback.

What's the difference between percent complete billing and minimum App 1 billing?

Percent complete bills you for the work you've put in place. Minimum App 1 billing tells you what you actually need to cover your costs and financing on the float. On most jobs, those two numbers aren't the same — and if you bill the lower one, you're the bank.

Want to see this across the whole job, not just App 1?

A 13-week cash flow forecast shows you every week where you're exposed — before it happens.

Get Your Forecast →