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Credit Series · Guide 11

Unitranche vs. First/Second Lien Guide

How direct lending structures actually work — the economics of unitranche, when first/second lien makes more sense, and the agreement among lenders that governs both.

Two structures dominate the leveraged lending market for sponsor-backed mid-market companies: the traditional first lien / second lien two-tranche structure that institutional credit markets have used for decades, and the unitranche facility that became the dominant product of the direct lending boom. Understanding both — their economics, their relative advantages, and the contractual mechanics that govern them — is foundational for anyone working in credit or direct lending.

We'll use a consistent example throughout: a sponsor acquiring a company with $100M EBITDA at a 10x entry multiple ($1 billion enterprise value). The sponsor contributes 45% equity ($450M) and finances the remaining 55% ($550M) with debt. The question is whether to structure that debt as a traditional two-tranche deal or a unitranche.

The Traditional First Lien / Second Lien Structure

In the classic two-tranche structure, the debt is divided into two separate facilities with different legal priority, pricing, and lender bases. First lien lenders hold a perfected first priority security interest in all assets; second lien lenders hold a second priority security interest, subordinate to the first lien.

1st Lien Term Loan
Amount$400M
RateSOFR + 375bps (~8.5% all-in)
Priority1st lien, senior secured
Amortization1% annually ($4M/yr)
LendersSyndicated to CLOs / institutions
Annual Interest$34.0M
2nd Lien Term Loan
Amount$150M
Rate11.0% fixed
Priority2nd lien, subordinate
AmortizationNone (bullet at maturity)
LendersDirect lenders / mezz funds
Annual Interest$16.5M
First / Second Lien — Cost of Debt Calculation
TrancheAmount ($M)RateAnnual Interest ($M)% of Total Debt
1st Lien TL$4008.50%$34.072.7%
2nd Lien TL$15011.00%$16.527.3%
Total$5509.18% blended$50.5100%

Blended cost = ($400M × 8.50% + $150M × 11.00%) / $550M = $50.5M / $550M = 9.18%

The two-tranche structure requires negotiation and documentation of an intercreditor agreement — a contract between the first lien and second lien lenders that governs enforcement rights, standstill periods, and behavior in a bankruptcy or restructuring. This adds complexity, legal cost, and execution time, but it also allows each tranche to be sized and priced to attract the right lender base.

The Unitranche Alternative

A unitranche facility is a single term loan that replaces both the first lien and second lien in one document. It is typically provided by one direct lender (or a club of direct lenders acting under one loan agreement) at a rate that sits between first lien and second lien pricing — reflecting the blended risk of a facility that occupies the full leveraged debt stack.

Unitranche Structure — Same Company, Single Facility
ItemDetails
Total Facility$550M
RateSOFR + 500bps (~9.25% all-in)
Annual Interest$50.9M
LenderSingle direct lender (e.g., Ares, Golub)
DocumentsOne credit agreement, no intercreditor
Amortization1% annually ($5.5M/yr)
Cost vs. Two-Tranche+7bps more expensive (9.25% vs. 9.18%)

The unitranche is marginally more expensive on an all-in basis — 9.25% vs. 9.18% blended in our example — but the premium buys real value: a single lender relationship, a single document to negotiate, and execution certainty that is significantly faster than syndicated market processes. For a sponsor trying to close a competitive auction, paying 7 basis points more to avoid a 4-week execution risk is almost always worthwhile.

The Agreement Among Lenders (AAL)

When a unitranche facility is held by multiple direct lenders rather than a single lender, there is an agreement among lenders (AAL) — a private contractual arrangement that splits the economics of the single loan into first-out and last-out tranches. Critically, the borrower sees only one loan. The AAL is invisible to the borrower and creates different economic arrangements purely between the lending syndicate members.

Under the AAL, the facility is divided economically:

The blended rate paid by the borrower (say 9.25%) is then allocated between first-out and last-out holders based on their respective shares. This arrangement allows two direct lenders with different risk appetites to co-invest in the same facility — a large, lower-risk fund takes the first-out position, and a more aggressive fund takes the last-out position.

AAL Split — $550M Unitranche with Two Lenders
TrancheAmount ($M)Economic RateAnnual Interest ($M)Recovery Priority
First-Out Portion$375M8.50%$31.9MPaid first in workout
Last-Out Portion$175M11.00%$19.3MPaid after first-out
Borrower's Blended Rate$550M9.31%$51.1MSingle facility

Borrower sees one loan at ~9.25-9.31%. The AAL split is invisible to the borrower — it only governs lender economics among themselves.

When to Use Each Structure

The choice between unitranche and first/second lien is driven by deal size, execution requirements, lender availability, and the sponsor's priorities.

Structure Comparison Matrix
DimensionUnitrancheFirst / Second Lien
Typical Deal Size$50M–$500M debt$300M–$2B+ debt
Execution Speed2–4 weeks6–10 weeks
ComplexityLow (one document)High (two facilities + ICA)
Cost9.00–11.00% all-in8.50–9.50% blended
Who ProvidesSingle direct lender or small clubSyndicated institutions / CLOs
Covenant PackageMaintenance covenants standardCov-lite common in BSL market
RelationshipSingle point of contactAgent bank + syndicate
Amendment ProcessCall one lenderBuild majority lender consent
Certainty of CloseVery high (lender committed)Market flex risk in syndication
Prepayment PremiumOften 1–2% soft call1% soft call in year 1 (TLB)

Unitranche is Preferred When

First/Second Lien is Preferred When

Direct Lender Economics

Understanding how direct lenders make money on unitranche deals matters for recruiting conversations — interviewers at Ares, Golub, and similar firms expect you to understand the business model, not just the credit analysis.

A direct lender originating a $400M unitranche at 9.25% earns $37M of interest income annually from that single position. But the all-in economics include several additional components:

Direct Lender Fee Anatomy — $400M Unitranche
Fee ComponentAmountTimingNote
Spread Income$37.0M / yrOngoing9.25% × $400M (declining as amortized)
OID (Origination Discount)$4.0M upfrontAt close1% of face value; amortized to yield
Commitment Fee (Revolver)$0.3M / yrOngoing50bps on $60M undrawn revolver
Amendment Fee (typical)$0.5–1.0MEpisodic25–50bps when borrower needs waiver
Exit Fee (if applicable)$2.0MAt prepayment50bps, uncommon but used in direct lending
All-In Yield (5yr hold)~10.1%BlendedInclusive of OID and fees amortized over 5 years

The OID is particularly important: even though the lender funds $400M, the borrower receives only $396M (after 1% OID). The lender has an effective yield higher than the stated coupon, because they paid less than par for the loan. This is why direct lenders report "all-in yield" rather than just the spread — the complete economic return includes origination economics.

Worked Example — Sponsor Chooses a Structure

Imagine a middle market sponsor is acquiring a specialty distribution company with $100M EBITDA at 10x ($1 billion enterprise value), using $550M of debt. Two lenders are competing for the mandate.

Option A — First/Second Lien (Syndicated Market)
ItemDetails
1st Lien TL ($400M)SOFR + 375bps (8.5%)
2nd Lien TL ($150M)11.0% fixed
Blended Rate9.18%
Annual Interest$50.5M
Execution Timeline7–9 weeks
Syndication RiskMarket flex ±50bps possible
Covenants1st lien cov-lite; 2nd lien maintenance
Post-Close ContactAgent bank; syndicate is distributed
Option B — Unitranche (Direct Lender)
ItemDetails
Unitranche ($550M)SOFR + 500bps (9.25%)
Blended Rate9.25%
Annual Interest$50.9M
Execution Timeline2–3 weeks (committed letter)
Syndication RiskNone — lender commits at signing
CovenantsMaintenance covenants (max leverage 6.0x)
Post-Close ContactDirect relationship; one decision-maker

The economics are nearly identical: Option A costs $50.5M annually; Option B costs $50.9M — a difference of $400K per year, or 0.07% of total debt. For a $1 billion company, this is irrelevant. The real decision factors are execution and relationship. In a competitive auction where the seller has set a 6-week exclusivity period, Option B's 2-3 week timeline provides a substantial advantage. If the deal breaks or refinancing is needed mid-hold, having a single counterparty to call is meaningfully simpler than rebuilding syndicate consent. The recommendation for this deal is clearly unitranche — the cost difference doesn't justify the execution risk of the syndicated market.

Why Unitranche Won the Direct Lending Market

The unitranche structure won because it solved the sponsor's real problem: certainty. Before unitranche became standard, every middle-market deal required two lender syndicates, two sets of documents, weeks of simultaneous negotiations, and a market flex risk that could reprice the deal after the sponsor had already committed to purchase price. Unitranche collapsed that complexity to a single relationship and a committed term sheet. The premium for that certainty — typically 50-75 basis points over blended two-tranche cost — is a rounding error on any leveraged buyout model. Direct lenders have happily charged it for two decades, and sponsors have happily paid it, because the alternative — a blown deal due to a syndication market that moved while you were in exclusivity — is far more expensive.

Common Interview Questions

Q: "What's the difference between a unitranche and a traditional first lien loan?"

A traditional first lien loan sits at the top of the capital structure with a subordinated second lien below it. A unitranche replaces both in a single facility, priced at a blended rate that reflects the full leverage risk of the combined stack. The unitranche lender takes on the economics of both tranches but benefits from a simpler document, a direct lender relationship, and typically maintenance covenants that the broadly syndicated market has eliminated. The key distinction is that a first lien lender in a two-tranche structure has a second lien cushion below them; a unitranche lender bears the full leverage risk from dollar one to the maximum commitment.

Q: "What is an AAL and when does it matter?"

An agreement among lenders governs how a unitranche facility is divided economically between multiple co-lenders. It creates first-out and last-out economics without changing the single-document structure that the borrower sees. The AAL matters in a workout: the first-out lender controls enforcement timing and recovers principal before the last-out lender, even though both hold the same facility legally. In a clean performing credit, the AAL is invisible. In a distressed situation, it can become the most important document in the deal — dictating who has control, who gets paid first, and whether the first-out and last-out lenders can coordinate or will fight each other for position.

Q: "Why would a sponsor prefer a direct lender to a bank for a mid-market deal?"

Speed, certainty, and simplicity. A direct lender provides a committed term sheet in one to two weeks, holds the loan without syndication risk, and remains a single point of contact for the life of the deal. Banks process middle market deals through syndication desks, which require 6-10 weeks of execution and introduce market flex risk. Beyond execution, direct lenders maintain meaningful maintenance covenants and have operational flexibility on amendments that a distributed syndicate cannot match. For any deal below $500M of debt, the premium for unitranche financing is almost always worth paying.

Next: Credit Fund vs. Bank Lending Practice in Mock Interview