An accreting swap is an interest rate swap whose notional principal grows on a preset schedule instead of staying constant, so the hedge matches a debt balance that is still being drawn up. It is the standard tool for construction loans, project finance, and any borrowing where funding arrives in stages. Set up correctly, the fixed-rate protection tracks the actual loan balance dollar for dollar. Set up poorly, you either pay fixed interest on money you haven’t borrowed yet or leave drawn funds exposed.
How It Differs From Other Swap Types
In a plain-vanilla interest rate swap, two parties exchange fixed-rate and floating-rate payments calculated on a notional principal that never changes. One side pays fixed; the other pays floating tied to a benchmark like Term SOFR. The notional itself never changes hands. It’s just the reference figure the payments are calculated on.
An accreting swap keeps that same fixed-versus-floating exchange but lets the notional step up over time on a predetermined schedule. Each period’s payment uses whatever notional applies to that accrual period, so early payments are smaller and later ones larger. An amortizing swap does the reverse: its notional shrinks over time to match a loan being paid down. A roller-coaster swap combines both, rising in some periods and falling in others.
The accreting version exists because a static notional creates an immediate mismatch when the underlying debt is still being funded. On a $100 million construction loan disbursed over 24 months, a vanilla swap on the full $100 million would have you paying fixed on the entire amount from day one, even if you had drawn only $5 million. An accreting swap starts near zero and steps up to $100 million in step with the draws, so the hedge and the debt stay aligned throughout.
The Notional Step-Up Schedule
The defining document is the step-up schedule in the swap confirmation. Under the ISDA framework, the Master Agreement provides the legal backbone governing defaults, termination, and netting, while each trade’s economics sit in a separate confirmation that prevails over the Master if the two conflict. The accreting schedule lives in that confirmation and specifies each date the notional will increase and the exact dollar increment.
Two flavors are common. A fixed schedule sets the notional to increase by a predetermined amount at regular intervals. If your lender will fund $10 million on the first of every month for ten months, the schedule locks in those ten steps. A variable schedule ties each increase to external events, such as construction milestones or formal lender draw notices. The swap notional steps up only after the draw actually happens, keeping the hedge tightly aligned with the real outstanding balance.
The initial notional may be zero, or a small amount representing an initial funding tranche. The final notional usually equals the full loan commitment. Whether the curve between those endpoints is linear, front-loaded, or back-loaded depends on the expected draw profile of the underlying debt.
For syndicated facilities, the swap’s floating-rate reference generally matches the common index used across the syndicate, most often one-month or three-month Term SOFR. The confirmation should also address what happens if the borrower doesn’t draw on schedule. Counterparties frequently agree on a “soft” linkage, where modest timing slippage doesn’t trigger an automatic amendment but a material deviation requires the parties to formally renegotiate the notional steps.
When to Use an Accreting Swap
The instrument earns its keep when funding grows over time and the borrower wants certainty on the all-in cost of capital.
Construction and Development Finance
A developer securing a $200 million floating-rate construction loan drawn over 18 months has two bad options without an accreting swap. A vanilla swap on the full $200 million creates negative carry from day one: the borrower pays fixed on money not yet drawn, with no offsetting floating payment on debt that doesn’t exist yet. A smaller static swap, say $100 million, leaves the upper half completely exposed once draws exceed that amount.
The accreting swap avoids both problems. If the loan funds in ten $20 million tranches, the notional steps up by $20 million on each draw date. Early in the project the developer hedges only what has been drawn. By the end of the draw period the full $200 million is covered.
Project Finance
Infrastructure and energy projects raise debt in phases tied to permitting milestones, equipment delivery, or site readiness. An accreting swap lets the project company lock in a fixed rate today on notional amounts that won’t materialize for months or years, insulating the long-term cost of capital from movements in the forward curve.
Phased Acquisitions and Capital Expenditure Programs
Corporate acquirers rolling up multiple targets on a set timetable, or manufacturers funding a multi-year equipment buildout, face the same phased-funding pattern. The accreting swap locks in the fixed rate across the whole series of future borrowings without forcing the borrower to hedge the full amount upfront.
Accreting Swap or Interest Rate Cap
Construction lenders often require the borrower to hedge, and the instrument choice isn’t always a swap. An interest rate cap is the main alternative.
A cap functions as insurance against rates rising above a specified strike. The borrower pays an upfront premium and receives payments whenever the floating rate exceeds the strike. If rates stay below the strike, the cap expires worthless. A swap, by contrast, locks in a fixed rate regardless of where floating rates go. You give up the benefit of declining rates in exchange for certainty.
The practical differences matter. A cap requires cash upfront, which strains liquidity during capital-intensive early months. A swap has no upfront premium but creates ongoing credit exposure between the counterparties, because at any point one side owes the other based on mark-to-market. A cap can never become a liability to the buyer once the premium is paid, so there is no risk of a termination payment if the project is sold or refinanced early. A swap can swing between asset and liability and terminating it can cost real money.
Lender preference varies. Some require a swap because it provides complete rate certainty for the project’s pro forma. Others accept a cap if the strike keeps all-in debt service within the coverage ratios. Check the loan agreement before choosing.
Why the Fixed Rate May Be Higher Than a Vanilla Swap
The fixed rate on any interest rate swap is set so the present value of the expected fixed-leg payments equals the present value of the expected floating-leg payments at inception, giving the contract zero value on day one.1CFA Institute. Pricing and Valuation of Interest Rates and Other Swaps The accreting structure doesn’t change that principle, but it changes the arithmetic. Each period’s cash flow is calculated on a different notional.
Each fixed-leg payment equals the fixed rate times the notional applicable to that period times the day-count fraction. Since the notional is lower early and higher later, the dollar amount of fixed payments grows over time even though the rate is constant. On the floating leg, each future period’s expected payment is projected using the implied forward rate from the current yield curve, applied to that period’s notional. Everything is discounted back using the zero-coupon curve, and the fixed rate is solved as the single rate that equates the two present values.
Because the larger notionals in later periods carry more weight in the calculation, the fixed rate is pulled toward the forward rates prevailing in those later periods. When the forward curve slopes upward, the accreting swap’s fixed rate will typically be higher than the rate on a vanilla swap of the same final maturity. In a flat or inverted curve environment, the difference narrows or reverses.
That matters for budgeting. A treasurer comparing a swap quote to an internal rate assumption needs to understand that the accreting structure isn’t just scheduling. It changes the fixed rate itself. The steeper the forward curve and the more back-loaded the notional schedule, the wider the gap.
What Happens When Draws Slip
This is where most accreting swaps run into trouble in practice. Construction timelines shift. If you draw slower than expected, the swap’s notional for a period exceeds your actual outstanding debt and you are over-hedged. If you draw faster, you are under-hedged. Either way, the effective rate you experience diverges from the rate you thought you locked in.
Consider a period where the swap notional is $25 million but you have drawn only $20 million. If rates have risen above your fixed rate, the swap produces a net receipt, but calculated on $25 million rather than the $20 million you actually owe. Your effective rate for the period drops below the swap’s fixed rate. That sounds like a windfall until rates move the other way: if rates fall below your fixed rate, you owe the dealer a payment on the full $25 million while your loan interest is based on only $20 million, and your effective rate exceeds the fixed rate you planned for.
The mismatch works in both directions, and neither is desirable when the whole point of the hedge was rate certainty. This is why the confirmation’s language on schedule amendments matters. A well-drafted agreement lets the borrower adjust the notional steps when the draw timeline shifts materially, rather than forcing everyone to live with a misaligned hedge or pay breakage to restructure.
Early Termination and Breakage Costs
An accreting swap can be unwound before scheduled maturity, and the cost is often the biggest financial surprise in the life of the contract. The termination payment, commonly called breakage, compares the original fixed rate to the prevailing market replacement rate for the remaining term. If the original rate exceeds the current market rate, the borrower pays the dealer to unwind. If the original rate is below the current market rate, the borrower receives a payment.
The dollar magnitude depends on the rate differential, the remaining term, and the notional outstanding at the time of termination. For an accreting swap that has already stepped up to a large notional, breakage can be substantial. A simplified example: a 4% fixed rate on $50 million notional with five years remaining, when the current five-year swap rate has fallen to 3%, produces breakage in the neighborhood of $2.5 million before day-count and present-value adjustments, roughly the present value of the 1% differential applied to $50 million over five years.
The risk is especially acute in construction finance, where projects get sold, refinanced, or shelved. Unlike a cap, which cannot have negative value to the buyer once the premium is paid, a swap can be a significant liability. Before signing, model termination exposure under several rate scenarios (particularly a sharp rate decline) and confirm the project or borrower can absorb the potential breakage. Section 6 of the ISDA Master Agreement governs early termination and close-out netting.2U.S. Securities and Exchange Commission. ISDA 2002 Master Agreement
Hedge Accounting
Borrowers using accreting swaps generally want cash flow hedge accounting under ASC 815, which lets gains and losses on the swap flow through other comprehensive income rather than hitting earnings each quarter. Without hedge accounting, fair-value changes run straight through the income statement, creating volatility unrelated to the project’s operating performance.
Qualifying requires formal documentation at inception. The borrower must identify the hedging instrument, the hedged item, the nature of the risk being hedged, and the method for assessing effectiveness, all before the hedge begins.3Financial Accounting Standards Board. ASU 2025-09 Derivatives and Hedging Topic 815 For an accreting swap hedging a construction loan’s floating-rate interest payments, the hedged item is the series of forecasted interest payments on each expected draw.
Ongoing effectiveness is the trickier part. If the swap’s notional schedule and the actual draws diverge significantly, the hedge may no longer be highly effective. Under recent amendments, if the hedged risks in a group of forecasted transactions become dissimilar, the entity must fully dedesignate the entire hedge. Losing designation means accumulated gains or losses in other comprehensive income get reclassified into earnings, and the borrower has to re-establish the hedge from scratch to get the favorable treatment going forward. Getting the notional schedule right isn’t just a hedging concern. It’s an accounting one.
Tax Treatment
Interest rate swaps are notional principal contracts under Treasury Regulation Section 1.446-3. The core rule: regardless of accounting method, the net income or net deduction from a swap for a taxable year is included in, or deducted from, gross income for that year.4Internal Revenue Service. Notional Principal Contracts
Periodic payments (the regular fixed-versus-floating exchanges on each settlement date) are recognized as the ratable daily portion of each payment for the taxable year to which it relates.5Internal Revenue Service. Revenue Ruling 2002-30 In practice, each settlement period’s net payment is ordinary income or an ordinary deduction. Because the accreting notional changes each period, the dollar amount fluctuates even when the rate differential is constant.
Nonperiodic payments, such as an upfront fee or a termination payment, are recognized ratably over the term of the contract in a manner reflecting the contract’s economic substance. If a swap includes a significant nonperiodic payment, the IRS may treat the arrangement as two transactions: an at-market swap plus a loan, with the time-value component recognized as interest rather than swap income.4Internal Revenue Service. Notional Principal Contracts
Reporting for Non-Financial End Users
Most borrowers entering accreting swaps are non-financial companies. These end users can avoid the Dodd-Frank central clearing requirement if the entity is not a financial entity, the swap hedges or mitigates commercial risk, and the counterparties report specified information to a registered swap data repository.6eCFR. 17 CFR 50.50 – Non-Financial End-User Exception to the Clearing Requirement
The reporting itself is light. The electing counterparty discloses whether it qualifies as a non-financial entity, confirms the swap is being used to hedge commercial risk, and identifies how it meets its financial obligations under the swap (posted collateral, a credit support agreement, a third-party guarantee, or its own resources). This can be done per trade or through an annual filing.7Commodity Futures Trading Commission. CFTC Public Information Collection Requirements 2025-21880 The swap still has to be reported to a swap data repository. Companies running many hedges across affiliates should also track aggregate notional, because activity above $8 billion in gross notional over a 12-month period can trigger swap dealer registration requirements.
Practical Points Before Signing
- Collateral: the dealer will almost certainly require a Credit Support Annex alongside the ISDA Master Agreement, obligating one or both parties to post collateral when mark-to-market moves against them. For an accreting swap with a large final notional, the potential call grows as the notional builds. Budget for that liquidity drag during the construction period, when cash is already tight.
- Legal costs: negotiating an ISDA Master Agreement, Schedule, and Credit Support Annex from scratch takes weeks and meaningful outside counsel fees. Many borrowers save time by using the same bank as both lender and swap dealer, which avoids a separate ISDA negotiation.
- Day-count conventions: the fixed and floating legs may use different day counts, such as 30/360 fixed and Actual/360 floating. That mismatch affects each settlement and creates small but persistent differences between the expected all-in rate and the actual rate. Match the swap’s conventions to the underlying loan’s conventions.
- Transition to amortizing: many construction loans convert to a permanent or mini-perm facility once construction is complete, and the hedge then needs to switch from an accreting profile to an amortizing one. Some borrowers negotiate this as a single roller-coaster swap with an accreting phase followed by an amortizing phase. Others terminate the accreting swap and enter a new amortizing swap, accepting any breakage on the first trade.