The paper LBO
The whole buyout on a notepad: entry, five years of cash repaying debt, exit, MOIC and IRR.
- Build a year of free cash flow: EBITDA less interest, tax and capex
- Carry the debt paydown through five years
- Calculate exit equity, MOIC and IRR, and check them with the rules of thumb
- Work out the highest entry multiple that still meets a target return
The intuition
You buy a flat to rent out, mostly with a mortgage. Each year the rent comes in; you pay the mortgage interest, the tax on your profit and the repairs, and put every dollar that is left toward the mortgage. The loan shrinks, so next year's interest is smaller and there is even more left over.
After five years you sell. The price, less the mortgage still owed, is what you walk away with. A paper LBO is exactly this, for a company, done by hand in an interview.
Each year: free cash flow = EBITDA − interest − taxes − capex, and all of it repays debt. At exit: equity = exit EBITDA × exit multiple − the debt left. Paydown feeds itself, because less debt means less interest.
Why it works
- The conventions, stated in every question: a five-year hold, D&A equal to capex, interest on the debt at the start of each year, tax charged after interest, flat working capital, all free cash flow repays debt, no fees.
- Each year. Interest = opening debt × rate. EBIT = EBITDA − D&A, and D&A = capex. Taxes = (EBIT − interest) × t. Free cash flow = EBITDA − interest − taxes − capex. Closing debt = opening debt − free cash flow.
- Tax comes after interest because this is the cash left for the owners after paying the lenders. The tax saving on interest is real cash in an LBO.
- At exit, enterprise value = year-5 EBITDA × exit multiple; subtract the debt still owed to get exit equity. MOIC and IRR follow.
- Rules of thumb over five years: 2.0x is about 15% a year, 2.5x about 20%, 3.0x about 25%.
- The most you can pay. Debt is sized off EBITDA, so paying more adds only equity. Exit equity ÷ target MOIC is the most equity you can put in; add the debt and divide by EBITDA for the highest entry multiple.
| Interest: 500 × 8% | 40.0 |
| EBIT: 100 − 15 | 85.0 |
| Taxes: (85 − 40) × 25% | 11.25 |
| Free cash flow: 100 − 40 − 11.25 − 15 | 33.75 |
| Closing debt: 500 − 33.75 | 466.25 |
Checks on the rules of thumb: 2.0^(1/5) − 1 = 14.9%, 2.5^(1/5) − 1 = 20.1%, 3.0^(1/5) − 1 = 24.6%.
The formulas
What is bought, borrowed and put in.
Interest on the start-of-year balance.
Cash left after lenders, tax and reinvestment.
Every dollar repays debt.
Sell, repay, measure.
The most you can pay for a required return.
Worked example
One year of the model. Interest first, then tax on what is left after interest, then capex.
See it move
Same deal. Change the growth, the interest rate, the capex, the leverage and the exit multiple.
- Raise the interest rate. Year-one interest rises, taxes fall by the tax rate × that rise, so free cash flow falls by only the after-tax part of it.
- Raise capex. EBITDA does not move, but free cash flow falls, less debt is repaid, and IRR drops.
- Add leverage. The equity check shrinks, but more interest leaves less free cash flow every year.
- Change the exit multiple. Nothing in the five years changes; only exit equity moves, by the change in multiple × year-5 EBITDA.
Run it backwards
Same deal, reversed: the fund needs a target multiple of money. What is the highest entry multiple you can pay?
The lenders lend the same turns of EBITDA whatever the price, so the debt, the five years of cash flow and the exit equity do not depend on the entry multiple. Exit equity ÷ target MOIC is the most equity you can put in. Add the debt for the most enterprise value, and divide by EBITDA.
This is why the winner of a competitive auction often earns the lowest return: every turn it bids above the others is paid entirely in equity.
Traps
Say it in the interview
“Walk me through a paper LBO.”
Check yourself
4 fresh questions, with new numbers. Answer each one correctly to finish the chapter. Get one wrong and you will see the full working, then you can try it again with new numbers.
Answers within 1% are marked right. Type the number; $, %, x and M are fine. First tries count toward Learned: the topic is Learned once every chapter is done and 75% of first tries were right.
- FCF = EBITDA − interest − taxes after interest − capex.
- All FCF repays debt; less debt means less interest next year.
- Exit equity = EBITDA₅ × exit multiple − debt left.
- 5 years: 2x ≈ 15%, 2.5x ≈ 20%, 3x ≈ 25%.