Financial Due Diligence Services UK
Financial Due Diligence support for buyers, sellers and investors — rigorous, fast, and delivered by a senior Fractional Finance Director with 30+ years’ experience. Oppenheim Advisory delivers independent financial due diligence across UK mid-market transactions, covering buy-side, sell-side, and vendor due diligence (VDD) for trade acquirers, private equity, and owner-managed businesses preparing for exit.
What Is Financial Due Diligence?
Financial due diligence is the independent review a serious acquirer, investor, or lender commissions before committing capital to a transaction. It tests whether reported profitability is real and sustainable, whether working capital and net debt positions are correctly stated, and whether the forecasts underpinning the deal are credible. A well-run diligence process confirms the numbers that drive valuation, surfaces hidden risks, and protects both sides from post-completion disputes. Unlike an audit, the focus is commercial and forward-looking: what does a buyer or investor actually own on day one, and what should they be willing to pay for it?
Buy-Side Due Diligence
Buy-side financial due diligence protects acquirers and investors from paying too much, or buying something different from what is advertised. We start with a red-flag review of the target’s accounts, management information, and data room, identifying anything that could affect price, deal structure, or completion mechanics. From there we build a Quality of Earnings (QoE) analysis, stripping out one-off, non-recurring, and owner-related items to arrive at a normalised, sustainable EBITDA. We run a detailed working capital analysis to set a defensible peg for completion accounts, and we surface every debt-like item — deferred consideration, unfunded liabilities, lease obligations, pension shortfalls, and aged accruals — so net debt at completion reflects reality. Our findings are translated directly into SPA negotiation points, price-chip rationale, and warranty coverage.
Sell-Side and Vendor Due Diligence
Sell-side and vendor due diligence (VDD) puts sellers on the front foot. Instead of waiting for buyers to find problems during their own diligence, we work through the business the way an acquirer will, pre-emptively identifying issues, cleaning up presentation, and building a defensible financial narrative. This protects value in three ways: buyers arrive at exclusivity with a tighter, cleaner picture; price chips and re-trades are materially less likely because known issues are already surfaced and explained; and management time during the transaction is preserved because most questions are already answered in the VDD report. For EOT, trade sale, and PE processes, a well-scoped VDD pack is often the difference between a clean completion at headline value and a drawn-out negotiation that erodes both price and certainty.
Our Approach
We run a structured, senior-led process tuned to the size and complexity of the deal:
- Scoping and kick-off — align on deal rationale, materiality thresholds, and key value drivers.
- Data room and information request — issue a targeted IRL and review accounts, management packs, and contracts.
- Analysis and QoE build — normalise earnings, test revenue quality, and validate working capital and net debt.
- Management Q&A and site visits — interrogate assumptions with the management team, on site where useful.
- Draft report and findings call — share red flags early so there are no surprises in the final document.
- Final deliverables — a written diligence report, a management presentation of findings, and data-room review notes ready to feed directly into SPA, completion accounts, and funder discussions.
What’s Included
Every engagement includes a structured document review covering statutory accounts, monthly management information, trial balances, and key contracts. We validate the KPIs that matter commercially — revenue by customer and product, gross margin, recurring vs non-recurring revenue, churn, and pipeline conversion — and reconcile them to the financial ledgers. A structured management Q&A session pressure-tests assumptions, and where the deal warrants it, we conduct an on-site visit to review operations, systems, and the finance function first-hand. Deliverables are practical and deal-ready: a concise diligence report, a QoE bridge, a working capital and net debt schedule, and a management presentation you can share with lenders, partners, or boards.
When You Need Financial Due Diligence
Financial due diligence should be on the table any time capital or control is changing hands. The most common triggers include a funding round where new investors need independent validation of the numbers, a trade sale where buyers expect a rigorous QoE and working capital analysis, an acquisition where you need comfort that the target is what it claims to be, an EOT transition where trustees and lenders need independent sign-off on valuation and affordability, and a PE bolt-on where an existing platform is adding a new business and needs fast, focused red-flag diligence. In every case, the earlier diligence starts, the more value it protects.
FAQs
See the FAQ section at the foot of this page for answers on scope, timing, QoE, vendor DD timing, and how we work alongside corporate finance and legal advisors.
Ready to Commission Financial Due Diligence?
Whether you are buying, selling, or investing, rigorous diligence pays back many times over in protected value and cleaner completions. Book a free consultation or call 07990 835891 to discuss your transaction in confidence, and we will scope a focused buy-side, sell-side, or vendor due diligence engagement that fits your timeline and deal.