MFN Clauses: How Lenders Keep From Getting Priced Out by the Borrower's Next Loan

"What happens if the company you just lent to turns around and borrows more money next month at a worse price for you?" is the plain-English version of the MFN interview question, and it trips up candidates who have the standard debt-financing vocabulary down cold but have never sat on the lender side of a credit agreement. MFN clauses show up in leveraged finance and private credit interviews specifically, and increasingly in general LBO interviews once the conversation moves past the paper LBO framework into how a real capital structure gets negotiated.

MFN stands for Most Favored Nation, a term borrowed from international trade law. In a credit agreement, it means the same thing it means in a trade deal: a party who gets a better deal elsewhere has to extend that better deal back to the party who already signed on. Applied to a leveraged loan, it means an existing lender's pricing gets protected if the borrower later raises new debt at a higher yield.

What an MFN Clause Actually Protects Against

Picture a borrower that raises a term loan priced at SOFR plus 350 basis points. Six months later, the same borrower goes back to the market for an incremental term loan to fund an acquisition, and market conditions have shifted, so the new tranche has to be priced at SOFR plus 425 basis points to clear. Without any protection, the original lenders are now stuck holding a loan that pays less than what the market currently demands for the same credit, while a newer lender captures the better rate for taking on essentially the same risk.

An MFN clause exists to stop that. It says that if the borrower incurs new debt priced above the existing loan's yield by more than an agreed cushion, the existing loan's pricing gets bumped up to close most of the gap. The lender who signed on first doesn't get stuck below market just because they were early.

This sits right next to the incremental debt capacity that funds a sponsor's add-on acquisitions: both provisions govern what happens when a borrower goes back for more money after the original loan closes. The incremental basket sets how much more debt the borrower can raise. MFN sets what that new debt is allowed to cost the existing lenders.

How the Repricing Mechanic Actually Works

The comparison isn't done on the headline interest rate alone. MFN clauses compare "all-in yield," which bundles together the interest rate margin, any interest rate floor, and original issue discount (OID), typically converted into an annualized yield assuming a four-year average life. A new loan issued at a lower margin but a steep discount to par can still trigger MFN if the all-in yield ends up higher once the discount is amortized in.

Lenders and borrowers negotiate a cushion, commonly 50 to 75 basis points, that the new debt's all-in yield can exceed the existing debt's yield by before MFN kicks in at all. Once the gap exceeds the cushion, the existing loan's margin (or floor) gets increased, not to fully match the new pricing, but to bring the gap back down to the size of the cushion.

A Worked Example

Say the existing term loan is priced at SOFR plus 350 basis points, with a 50 basis point MFN cushion. The borrower later needs to raise an incremental term loan, and the market requires SOFR plus 425 basis points to get it done.

The gap between the two, 75 basis points, exceeds the 50 basis point cushion, so MFN is triggered. The existing loan doesn't get bumped all the way up to SOFR plus 425. It gets bumped up just enough to bring the gap back within the cushion, to SOFR plus 375. The original lenders end up 25 basis points better off than where they started, still below the new tranche's pricing, but no longer left behind by the full 75 basis point move.

That's the entire mechanic in one number: MFN doesn't guarantee existing lenders match new money. It guarantees they never fall more than the cushion behind it.

What Debt Is Excluded From MFN Protection

MFN doesn't apply to every dollar of new debt a borrower raises, and knowing the carve-outs is usually what separates a candidate who has actually read a credit agreement from one who has only heard the concept described. The most common exclusions are:

• Ratio-based incremental debt, where the borrower is adding debt under a leverage-ratio test rather than under a fixed incremental basket, is frequently carved out or given a wider cushion, since the original commitment parties negotiated a different, more permissive lane for that debt.
• Debt with meaningfully longer maturity, typically anything maturing more than one to two years after the existing term loan, on the logic that a lender taking longer-dated risk deserves to be paid for it without triggering a repricing of the shorter-dated tranche.
• ABL revolvers and other asset-backed facilities, which are underwritten and priced off collateral rather than credit spread in the first place, the same distinction covered in asset-based lending vs. cash flow lending, so comparing their pricing to a cash flow term loan's yield doesn't map cleanly onto the MFN test.
• Notes and high-yield bonds issued in lieu of loans, which trade in a different market with a different pricing convention and are often excluded entirely or subject to a separate, looser MFN standard.

Each of these exists because the original lender group negotiated a narrower scope for its own protection in exchange for something else, usually a lower spread, a smaller commitment, or faster execution. The takeaway for an interview answer is that MFN is a negotiated commercial term, not a blanket rule, and the exclusions are exactly where sponsors fight hardest to preserve flexibility to raise cheap debt later without repricing the existing stack.

The MFN Sunset Provision

A sunset provision lets MFN protection expire entirely after a set period, commonly somewhere in the 6 to 18 month range, after which the borrower can raise new debt at any price without triggering a reprice of the existing loan.

Sunsets are one of the more contested terms in leveraged loan documentation. Lenders generally push to keep MFN protection permanent, since the whole point of the clause is to guard against being priced out for as long as the loan is outstanding, and a sunset just delays that risk rather than eliminating it. Borrowers and sponsors push for a sunset because it gives them a known window after which they can layer in acquisition financing or refinance more aggressively without having to reprice the original facility.

Which side wins that negotiation tracks the broader leveraged loan market. When capital is chasing too few deals and terms skew borrower-friendly, sunsets get included and get shorter. When lenders have more leverage in a given cycle, sunsets get dropped from the documentation entirely and MFN protection just runs for the life of the loan. An interviewer asking about sunsets is often really asking whether you understand that credit agreement terms move with supply and demand for loan paper, not just with the credit quality of any one borrower.

Common Follow-Up Questions

"Why would a lender ever agree to a sunset instead of permanent MFN?" Pricing and speed. A borrower willing to accept a shorter sunset, or none at all, can often get a tighter initial spread, since the lender is being compensated elsewhere for giving up permanent protection. In a competitive underwriting process, sponsors use that tradeoff to win better terms up front.

"Does MFN protection apply to the revolver too, or just the term loan?" Typically just the term loan. Revolving facilities are priced and used differently, for working capital and liquidity rather than long-term leverage, and are usually carved out of the MFN comparison entirely, similar to how ABL facilities get excluded.

"What stops a borrower from just structuring new debt to dodge MFN?" Nothing in principle, and it happens. A borrower can lean on whichever carve-out is available, ratio debt, a note offering instead of a loan, or debt with a longer maturity, specifically because it falls outside the MFN test. That's exactly why the exclusions matter as much as the core mechanic itself when you're evaluating how protective a given credit agreement actually is.

"How is this different from a make-whole or call protection?" Those protect a lender against the borrower repaying the loan early. MFN protects a lender against the borrower issuing new debt on top of the existing loan at a better price. One is about getting paid off too soon, the other is about getting left behind while still holding the paper.

Getting Comfortable With the Mechanic

The framework above covers what most interviewers are testing: what MFN protects against, how the all-in yield comparison and cushion actually reprice the existing loan, which debt gets carved out and why, and how sunset provisions shift with the leveraged loan cycle. Offcycle has this alongside the broader debt and capital structure mechanics that come up in the same conversation, including how debt capacity gets sized in a full LBO walkthrough, built into structured flashcards and quizzes you can work through by topic and difficulty.

Beyond flashcards, you get custom practice sets built around whatever you're weakest on, mock interview questions that test the same material out loud, and a readiness score that tracks your progress across LBO, valuation, and credit topics so you know exactly where the gaps are before you're in the room.