A practical guide to working capital due diligence — how PE, search funds, and M&A teams set a fair net working capital peg, read DSO/DIO/DPO, catch balance-sheet dressing, and protect purchase price at close.
Working capital due diligence answers a cash question: on the day you wire purchase price, will the business hand over a normal operating balance sheet — or one stripped of cash through accelerated receivables, stretched payables, and inventory games?
Deal teams define net working capital (NWC) in the SPA (often current assets less current liabilities, with cash, debt, and debt-like items carved out). They then set a target / peg based on a normalized history. Closing NWC above or below the peg drives a dollar adjustment. Miss the definition or the seasonality, and you overpay without realizing it until the true-up fight.
WC diligence sits next to quality of earnings (QoE) inside financial due diligence. QoE asks whether earnings are real and cash-backed. WC diligence asks whether the balance sheet that converts those earnings is fair at close.
| Work product | Primary question | Typical owner | Output |
|---|---|---|---|
| Quality of earnings | What is sustainable cash EBITDA? | QoE / FDD | Adjustment bridge |
| Working capital DD | What NWC is normal at close? | FDD / ops finance | Peg + bridge + true-up |
| Debt-like schedule | What looks like debt at close? | FDD / legal | Purchase-price deductions |
| Full financial DD | Full financial risk package? | Buy-side advisors | QoE + WC + tax + systems |
| Public-info first pass | Is this name worth exclusivity fees? | Deal team / screening | Kill flags + IC questions |
Current assets / liabilities scope, cash & debt carve-outs, deferred revenue treatment, and how the peg true-up is calculated (collar, dollar-for-dollar, average of months).
DSO trend, aging buckets, allowance policy, concentration, disputes, factoring, and bill-and-hold. Growth that only appears as AR is not cash.
DIO, costing method, obsolescence, slow-moving SKUs, consignment, and capitalization. Rising inventory with flat sales is a classic yellow flag.
DPO stretch, critical-vendor terms, accrued expenses completeness, payroll timing, and whether AP was extended to dress cash for sale.
12–24 month history, peak WC needs, backlog and order book, and whether the proposed peg matches the closing month of the year.
Customer deposits, gift cards, deferred revenue over-funding, unpaid taxes, warranty, litigation reserves, related-party payables.
| Method | When it fits | Watch-outs |
|---|---|---|
| Trailing 12-month average | Stable, low-seasonality ops | Masks recent deterioration |
| Trailing 12 monthly average of NWC | Standard mid-market PE | Needs clean monthly closes |
| Same-month prior-year average | Strong seasonality | Requires multi-year history |
| Normalized target days (DSO/DIO/DPO) | Ops improvement thesis | Do not bake unproven ops gains into price |
| Collar around peg | Negotiation compromise | Can hide material misalignment |
Document every policy difference between management reporting and SPA definition. Many true-up disputes are definition fights, not arithmetic fights.
A working capital bridge explains the change in NWC between two points (e.g., last year vs LTM, or LOI vs close). Split each line into volume, price/mix, policy, one-time, and unexplained residual. Unexplained residual is where quality problems hide.
Pair the bridge with cash conversion: if EBITDA is up but free cash is flat, the WC investment is the first place to look (alongside capex and debt-like builds).
Working capital modeling inside full financial diligence often sits inside $40K–$250K+ QoE/FDD packages and multi-week data rooms. A structured public-info pack at $49 (or $39.20 with launch code) will not replace confirmatory accountants — it kills weak names before you burn exclusivity and fee budget.
| Signal | Severity | Why it matters |
|---|---|---|
| DSO rising faster than revenue for 2+ quarters | High | Collection / quality risk; earnings not cash |
| AP DPO spikes only in sale-process months | Deal-Killer | Cash dressed for sale; peg will true down |
| Inventory turns down while gross margin up | High | Possible overstatement or aging stock |
| Customer >25% of AR with disputes | High | Concentration + collectability |
| Factoring / reverse factoring undisclosed | High | True leverage and WC needs misstated |
| Large deferred revenue without delivery backlog | High | May be debt-like, not operating liability |
| Related-party AR/AP material | High | Arm’s-length and collectability risk |
| No monthly closes / WC swings unexplained | Deal-Killer | Cannot set a defensible peg |
Interactive checklist for IC prep. Tag severity as you work: Deal-Killer / High / Watch.
| Approach | Typical cost | Timeline | Best use |
|---|---|---|---|
| Full FDD / QoE with WC deep dive | $40K–$250K+ | 2–6 weeks | Confirmatory under exclusivity |
| Boutique WC-only model | $15K–$75K | 1–3 weeks | Complex seasonality / manufacturing |
| Internal PE associate model | Team time | Days–weeks | Repeatable platforms with clean ERP |
| Public-info first-pass pack | $49 ($39.20 with code) | Minutes | Pre-LOI kill screen across many names |
For process timing context, see the M&A deal timeline and M&A due diligence process guides.
Often as a starting point, but SPA definitions vary. Cash, debt, income taxes, and debt-like items are frequently excluded. Always underwrite the definition, not the textbook formula.
It depends on the business. Subscription and gift-card models often treat excess deferred revenue as debt-like. Delivery obligations and cost-to-serve must be modeled either way.
Common in some retail, software, and marketplace models (customers pay first). The peg still matters — negative NWC can be a feature, but deterioration (less negative) still costs the buyer cash at close.
Enterprise value assumes a normal WC level. If you pay for normalized EBITDA but inherit a stripped balance sheet, you effectively overpaid. See how to value a company for acquisition.
Rising DSO language in filings, inventory build commentary, supplier stretch, factoring disclosures, going-concern notes, and customer concentration in risk factors. None replace data-room work; all help prioritize screens.
No. Operational due diligence explains capacity and process; WC diligence quantifies cash tied in the cycle. Use both on manufacturing and distribution deals.
Definition summary, 24-month NWC chart, DSO/DIO/DPO trends, top customer/vendor concentration, debt-like list, proposed peg method, and open questions for the data room.
No. dodilligence delivers structured first-pass research from public information to support screening and IC questions. It is not an audit, fairness opinion, or SPA calculation.
Order a institutional-style first-pass diligence PDF on any public or private name — useful kill flags and IC questions before exclusivity and FDD fees stack up.