Mezzanine Debt in LBO Capital Structures

Mezzanine debt sits between senior secured debt and equity in an LBO capital structure — higher risk, higher return, and often the difference between a deal that gets done and one that doesn't. When senior lenders cap leverage at 4.0x EBITDA but the sponsor wants 5.5x total leverage, mezz fills the gap. Understanding how mezz works, how it affects the debt schedule and returns, and when it makes sense is essential for PE interviews — especially at firms that run multi-tranche LBO models.

Where mezz fits in the capital structure

Priority (highest to lowest):
  1. Revolver (senior secured, first lien)
  2. Term Loan A / Term Loan B (senior secured)
  3. Mezzanine / Subordinated Debt (second lien or unsecured)
  4. Preferred Equity (if any)
  5. Common Equity (sponsor + rollover)

Each layer has higher risk and demands higher return:

| Tranche | Typical Rate | Cash vs. PIK | Leverage Range | |---------|-------------|-------------|----------------| | Senior Term Loan | SOFR + 250–400 bps | Cash-pay | 3.0–4.5x EBITDA | | Unitranche | SOFR + 450–600 bps | Cash-pay | 4.0–5.5x EBITDA | | Mezzanine | 10%–14% total | Mix of cash + PIK | Adds 1.0–2.0x EBITDA | | Equity | 20%+ IRR target | — | Plug |

Why sponsors use mezz

Higher total leverage without more equity:

Target: 5.5x total leverage on $100M EBITDA
Senior capacity: 4.0x = $400M
Mezz needed: 1.5x = $150M
Total debt: $550M
Equity required: EV − $550M (instead of EV − $400M)

Mezz reduces the equity check by $150M — improving fund-level returns if the deal performs (same exit equity from a smaller equity investment = higher MoIC).

Tradeoff: mezz is expensive (10%–14% all-in) and grows via PIK if cash interest isn't paid. It eats into exit equity if the company underperforms.

Mezz terms and structures

Cash-pay vs. PIK

All-Cash Mezz: 12% cash interest, no PIK → $150M × 12% = $18M/year cash cost
PIK Mezz:       8% cash + 4% PIK → $12M cash + $6M added to principal annually
Full PIK:     0% cash + 13% PIK → $0 cash, $19.5M added to principal in Year 1

Full PIK preserves cash for operations and senior debt service but compounds the mezz balance rapidly. A $150M PIK mezz tranche at 13% PIK grows to $276M over 5 years if unpaid — consuming $126M of exit equity.

Warrants and equity kickers

Mezz lenders often receive warrants (equity options) as additional compensation:

• Typically 2%–10% of fully diluted equity
• Exercise price at current equity value
• Aligns mezz lender with equity upside

In returns modeling, warrants dilute sponsor equity slightly at exit but are usually immaterial (under 5% dilution).

Intercreditor agreements

Senior and mezz lenders sign an intercreditor agreement governing:

• Payment priority (senior always paid first)
• Standstill periods (mezz can't declare default for X months after senior default)
• Blockage rights (senior controls enforcement decisions)
• PIK restrictions (mezz may be prohibited from PIK-ing if senior covenants are breached)

You don't model intercreditor details in an interview LBO, but knowing they exist shows sophistication.

Modeling mezz in a debt schedule

Add a separate tranche below senior debt:

Mezzanine Tranche:
  Beginning Balance: $150M
  Cash Interest: Beginning Balance × Cash Rate (e.g., 8%)
  PIK Interest: Beginning Balance × PIK Rate (e.g., 4%) → added to balance
  Ending Balance: Beginning + PIK Accrual − Amortization (usually zero — bullet at exit)

Waterfall priority for cash flow:

1. Revolver interest and mandatory amortization
2. Senior term loan interest and cash sweep
3. Mezz cash interest (if cash-pay component)
4. Any remaining cash to equity (rare in early years)

Mezz typically does not receive cash sweep prepayment — it amortizes on schedule or pays off at exit as a bullet.

Impact on returns

Without Mezz (4.0x leverage):
  Entry Equity: $300M
  Exit Equity: $450M
  MoIC: 1.50x

With Mezz (5.5x leverage):
  Entry Equity: $150M
  Exit Equity: $350M (reduced by mezz payoff of $200M+)
  MoIC: 2.33x

Higher MoIC from smaller equity check — but exit equity is reduced by the larger mezz balance at exit. If the company underperforms, mezz PIK compounding can eliminate exit equity entirely.

When mezz makes sense vs. doesn't

Good mezz candidates:

• Strong, stable cash flow covers senior debt service with room for mezz cash interest
• Sponsor wants higher leverage without contributing more equity
• Company has low capex needs (more cash available for debt service)
• Exit visibility is strong (mezz will be repaid at exit)

Bad mezz candidates:

• Cash flow barely covers senior debt — mezz cash interest adds unserviceable burden
• High capex or cyclical business — cash flow too volatile for additional debt layer
• Long hold with full PIK mezz — compounding eats exit equity
• Company in decline — mezz PIK accelerates the equity destruction

Common interview questions

"What is mezzanine debt?" Subordinated debt between senior secured and equity. Higher rate (10%–14%), often includes PIK component, fills the gap when senior lenders won't provide full leverage. Repaid after senior debt at exit.

"Why use mezz instead of more equity?" Reduces the equity check, improving MoIC if the deal performs. Mezz is cheaper than equity (10%–14% vs. 20%+ IRR target) but more expensive than senior debt.

"How does PIK mezz affect exit equity?" PIK interest compounds the mezz balance instead of being paid in cash. At exit, the larger mezz balance reduces equity proceeds dollar-for-dollar. Over a 5-year hold, PIK can grow the balance by 50%–80%.

"Walk me through a multi-tranche debt schedule." Senior term loan (cash-pay, cash sweep) → mezz (cash + PIK, bullet at exit) → equity. Cash flow waterfall: senior first, then mezz cash interest, then equity. At exit: pay senior, pay mezz, remainder to equity.

The takeaway

Mezzanine debt is the lever that lets sponsors do deals at higher total leverage without putting up more equity — but it comes at a cost that compounds if the company underperforms. PE interviewers test whether you understand the waterfall, can model PIK accretion, and know when mezz helps vs. hurts returns. Build the multi-tranche schedule cleanly and the returns story follows.