How to Build an LBO Model Step by Step | Wizenius

An LBO model is built in a fixed sequence, not a flexible one. You start with the entry price, then sources and uses, then the opening balance sheet, then the operating model, then debt, then cash flow, then exit returns, then sensitivity. Each step produces a number the next step needs. Build out of order and the model will not tie.

Ask most students to sketch an LBO and they will start listing formulas: EBITDA multiple, IRR, cash sweep. Ask them which one comes first and the answers scatter. That gap between knowing the pieces and knowing the sequence is exactly what a PE or IB interviewer probes for.

It shows up in a specific way. A candidate builds a debt schedule before deciding how the deal is funded. Or calculates returns before the balance sheet has been rebuilt for the new owner. The model technically has all the right formulas in it, and it still will not balance, because balancing depends on order, not just accuracy.

This article walks through the build sequence properly, step by step, with the reasoning behind each one. Treat it as the map you check before you open Excel, not something you memorise the night before an interview.

What is the correct order to build an LBO model?

An LBO model is built in eight steps, each one feeding the next: entry assumptions, sources and uses, transaction adjustments, the operating model, the debt schedule, free cash flow, exit and returns, and sensitivity analysis.

Step	What it does	What it hands to the next step
1. Entry assumptions	Sets the purchase price	Enterprise value at entry
2. Sources and uses	Decides how the deal is funded	Debt and equity amounts
3. Transaction adjustments	Rebuilds the opening balance sheet	Starting balances for the model
4. Operating model	Projects revenue, EBITDA, margins	EBITDA feeding the debt schedule
5. Debt schedule	Tracks interest, repayment, cash sweep	Interest expense and closing debt
6. Free cash flow	Cash left after interest, tax, capex	Cash available to sweep debt
7. Exit and returns	Sells the business, calculates MOIC and IRR	The final answer
8. Sensitivity	Stress-tests the return	Which assumptions actually matter

Keep this table next to your model as a checklist. If you find yourself stuck on step five and the answer depends on something from step two, that is usually the sign you built out of order rather than made a formula error.

Why must entry assumptions come first in an LBO model?

Entry assumptions come first because the purchase price sets enterprise value, and almost every other number in the model is built on top of that figure.

The purchase price is usually entry multiple times EBITDA. If the sponsor is paying 9 times EBITDA on a company earning INR 200 crore of EBITDA, the enterprise value at entry is INR 1,800 crore. That single number decides how much debt and equity the deal needs, what the opening balance sheet looks like, and what the exit has to clear for the sponsor to earn a reasonable return.

Get this number wrong, or build it after other steps, and you are not building an LBO. You are guessing at inputs and hoping the model happens to work.

How do sources and uses work in an LBO?

Sources and uses is the funding plan for the deal, and the two sides must add up to exactly the same total.

Uses is what the money is spent on: the purchase price from step one, plus transaction fees and financing fees. Sources is where that money comes from: new debt raised for the deal, sponsor equity, and any equity rolled over by the existing owners.

If uses come to INR 1,900 crore, sources must also come to INR 1,900 crore. This is the most common place a model breaks in an interview setting, usually because a fee was left out of uses or a debt tranche was left out of sources. When your sources and uses do not tie, stop and check every line before moving forward, because nothing built after this step will be correct either.

What happens in the transaction adjustments step?

Transaction adjustments rebuild the balance sheet for the new owner on day one of the deal, replacing the old capital structure with the new one.

Three things happen here. The old equity is written off, since the previous owners have been bought out. The new debt and sponsor equity from sources and uses are added in. And goodwill is created to plug the difference between what was paid and the fair value of the net assets acquired, with deal fees typically expensed or capitalised depending on the fee type.

This step is easy to underrate because it produces no exciting formulas, only a rebuilt balance sheet. But every year of the projection period starts from this opening balance sheet, so an error here compounds silently through the entire model.

How does the debt schedule and cash sweep work in an LBO?

The debt schedule tracks how much is owed on each tranche of debt, how much interest accrues, and how quickly the debt gets paid down using spare cash.

Each tranche of debt has its own interest rate and its own mandatory repayment schedule, usually a fixed percentage of the original principal each year. On top of mandatory repayment sits the cash sweep, which takes any free cash flow left over after mandatory obligations and uses it to pay down debt early, most commonly the most expensive or most senior tranche first. A revolver sits underneath all of this as a safety net, drawn on only if cash flow falls short of what is needed to cover interest and mandatory repayment in a given year.

This is where leverage actually gets tested. A business with strong, steady free cash flow can sweep debt down fast and improve returns. A business with lumpy or weak cash flow may barely touch the cash sweep, which is exactly why lenders and sponsors both study the cash flow profile so closely before agreeing to leverage a deal.

How do you calculate exit returns: MOIC and IRR?

Exit returns are calculated by selling the business at an assumed exit multiple, working out what equity value is left after paying off remaining debt, and comparing that to the sponsor's original equity investment.

Exit enterprise value is usually exit multiple times exit year EBITDA. Exit equity value is exit enterprise value minus whatever debt is still outstanding at that point, which is why paying down debt faster through the cash sweep directly improves the equity return, even if the exit multiple stays flat.

From there, MOIC is simply exit equity value divided by the original equity invested. IRR, or XIRR if cash flows are irregular, converts that multiple into an annualised return, accounting for how many years the sponsor's capital was tied up. A 2.5x MOIC over three years is a very different outcome from a 2.5x MOIC over seven years, and IRR is what makes that difference visible.

Why does sensitivity analysis matter in an LBO?

Sensitivity analysis shows which assumptions actually move the return, and in most LBOs it comes down to four: entry multiple, exit multiple, leverage, and EBITDA growth.

A base case return of, say, a 22% IRR means little on its own. What matters is how that number moves if the exit multiple compresses by one turn, or if EBITDA growth comes in two points lower than modelled. Building a simple two-way data table around entry and exit multiples, or around leverage and growth, is usually enough to show an interviewer, or a real investment committee, which risks the return is actually exposed to.

Building the sequence into habit

None of these eight steps is difficult on its own. The difficulty is in resisting the urge to jump to the exciting part, the returns, before the earlier steps have been built properly. Every experienced analyst learns this the same way: by building a model out of order once, watching it fail to balance, and going back to fix the sequence rather than the formulas.

FAQ

In what order should I build an LBO model?

Build in this sequence: entry assumptions, sources and uses, transaction adjustments, the operating model, the debt schedule, free cash flow, exit and returns, then sensitivity. Each step supplies an input the next step needs.

Why does my LBO model not balance?

Usually because sources and uses do not tie, or because the transaction adjustments step was built incorrectly, so the opening balance sheet is wrong. Check these two steps before assuming a formula error elsewhere.

What is a cash sweep in an LBO?

A cash sweep uses free cash flow left over after interest, tax, mandatory debt repayment and capex to pay down debt early, usually starting with the most senior or most expensive tranche.

What is the difference between MOIC and IRR?

MOIC is exit equity value divided by the original equity invested, a simple multiple. IRR annualises that return, accounting for how many years the capital was invested, so it reflects the speed of the return, not just its size.

Which assumptions matter most in an LBO sensitivity table?

Entry multiple, exit multiple, leverage, and EBITDA growth typically drive most of the movement in return outcomes, which is why these four are the standard sensitivity table in most LBO models.

Where do you usually see LBO models break down when you build them, at the balance sheet stage, the debt schedule, or the returns? If the build order still feels shaky, our financial modelling course walks through a full LBO build from entry assumptions to exit, step by step, in the same sequence covered here.