Profitable contractors go broke through timing, not losses. Billing cadence, unbilled WIP, imprest discipline and receivables ageing — the four controls.

Construction has a cruel financial signature: you spend money every single day — wages weekly, diesel daily, suppliers monthly — and you receive money in lumps, 45 to 120 days after the work, minus retention, minus advance recovery, minus whatever the certifying engineer trimmed. A contractor can be profitable on every project and still miss a wage payment, because profit is an opinion about the whole job; cash is a fact about this Friday. Most contractor failures are cash-timing failures, not loss-making failures. The protection is four disciplines: billing cadence, unbilled WIP control, imprest discipline, and receivables ageing.

Know Your Project's Cash Shape

Map any project's cash curve and it dips before it climbs: mobilisation costs precede the advance, every month's execution precedes its RA bill, and the certified bill precedes payment by whatever your client's file speed is. The working capital a project consumes is roughly its monthly run rate multiplied by the total lag between spending and receiving — spend ₹1.5 crore a month with a three-month lag and that project permanently borrows ₹4.5 crore from you. Two consequences follow. First, growth eats cash: every new project adds its own borrowed float, which is why expanding contractors feel poorest exactly when the order book looks best. Second, every week you shave off the lag returns real money permanently — which is what the next three disciplines do.

Discipline 1: Billing Cadence — the Bill Is the Business

The single highest-leverage habit in contracting: bill every cycle the contract allows, on the same date, without exception. Not when quantities are "substantial", not when the engineer is free — every cycle. What actually delays bills is never the client's 14-day certification clause; it is the four weeks your own team spends assembling quantities from site diaries, hunting test certificates, and re-arguing measurements that should have been recorded at execution. The fix is continuous measurement: quantities logged daily against BOQ items, with photos and joint measurements attached at source, so the abstract already exists on billing day. That is precisely the flow BOQ & billing automates — the bill becomes a review, not a reconstruction. Contractors who make this one change routinely pull weeks of receivables forward, permanently. And submit formally: a bill under a numbered covering letter with an acknowledgment starts the contractual payment clock; a bill handed over loosely starts nothing.

Discipline 2: Unbilled WIP — the Silent Cash Sink

Unbilled work-in-progress is work you have executed and paid for that has not yet entered any bill — the gap between your cost line and your billing line. It hides everywhere: the fortnight of progress since the last bill (unavoidable), plus extra items awaiting written instructions, quantities awaiting joint measurement, and variations "to be settled at the end" (all avoidable, all corrosive). Unbilled WIP is the most dangerous number in a contractor's finances precisely because no one reports it: costs show up in the ledgers, billing shows up in the bank, but the gap between them lives nowhere unless you measure it. Run the number monthly per project: cost incurred to date minus amount billed to date. A healthy project carries less than one month of run rate; a project carrying two or three is lending its client crores interest-free — or worse, hiding work that will never be paid because the paper trail was never built. Cap it with rules: no extra item executed beyond a small threshold without a written instruction logged the same day, and a monthly WIP review where every ageing unbilled rupee needs a named reason and an owner.

Discipline 3: Imprest Discipline — the Small Leak That Sets the Culture

Site imprest — the petty cash float for daily expenses — is small money that teaches your organisation how it treats all money. Loose imprest looks like this: irregular top-ups on urgent phone calls, vouchers written from memory at settlement time, "miscellaneous site expenses" absorbing whatever cannot be explained, and advances to staff that quietly age into write-offs. Tight imprest is boringly simple:

A fixed float per site, sized to roughly a fortnight of genuine petty spend — replenished only against settled vouchers, so the float itself polices documentation
Voucher at the moment of spend, with a photo of the receipt, categorised then and not at month-end
Weekly settlement reviewed against category norms, with anything above a threshold pre-approved before spending, not ratified after
Staff advances tracked as a ledger with ageing — an advance is a receivable from an employee, and it behaves like every receivable: it goes bad with age

Beyond the direct leak, sloppy imprest destroys your cost data — expenses booked late and vaguely make every project cost report a fiction at exactly the granularity where margins are decided.

Discipline 4: Ageing Receivables — Collections Is a Process, Not a Phone Call

Certified bills do not pay themselves. Run a monthly ageing of every receivable — 0–30, 30–60, 60–90, 90-plus days — and treat each bucket as a different job: 0–30 is follow-up, 30–60 is escalation to the client's decision-maker with the contractual interest clause mentioned in writing, 90-plus is a director-level conversation and a brake on further exposure. Three refinements that separate professionals from optimists:

Track certified and uncertified separately. A bill sitting uncertified for six weeks is not a receivable, it is a dispute incubating — chase certification harder than payment.
Age your retention too. Retention released after DLP is a receivable with a three-year fuse; it needs diary dates, or it becomes a donation.
Price the delay into the relationship. A client who structurally pays at 120 days costs you 2 to 3 percent of contract value in financing — that belongs in your next quote to them, or in the decision not to bid.

Two Timing Levers Most Contractors Leave Unpulled

Beyond the four disciplines, two contractual levers move cash without moving a single brick. First, the mobilisation advance: where the contract offers one, take it, price its interest honestly, and spend it on mobilisation — the firms that burn the advance plugging older projects' holes have converted a cushion into a trap, because recovery deductions start with the very first bill regardless. Second, GST timing: tax is payable on invoicing, not on collection, so a certified bill your client sits on still triggers your output liability by the 20th of the next month — one more reason the billing and follow-up cadence is a cash discipline, not an accounting one. Align input credits the same way: booking supplier invoices promptly, with GRNs in place, keeps credit flowing in the same month the cash flowed out.

Put the Four on One Screen

Each discipline is simple; the power is running them together, monthly, per project: billing on cadence, WIP under one month, imprest settled weekly, ageing reviewed with owners. A 13-week rolling cash forecast — committed outflows against realistically-dated inflows — turns the review from history into steering. This is what financial control is built for: cost, billing, WIP and ageing per project on one dashboard, fed by the site's daily entries rather than month-end typing. Put your own billing lag and WIP numbers into the ROI calculator and see what a two-week improvement is worth on your turnover — for most mid-size contractors it outweighs a year of rate negotiations.

Margin decides whether the business is worth running; cash decides whether it survives long enough to collect the margin.

Book a ProjectSathi demo and see billing, WIP and receivables ageing come off your sites' daily data instead of month-end spreadsheets.