Arbitrage Rebate Requirements: Deadlines, Exceptions, and Penalties

Arbitrage rebate requirements force state and local governments that issue tax-exempt bonds to return to the U.S. Treasury any investment earnings on bond proceeds that exceed what the proceeds would have earned at the bond’s own yield. The rule sits in Section 148(f) of the Internal Revenue Code, and missing it can cost an issuer the tax-exempt status of the bonds themselves.¹ Because tax-exempt borrowing rates run below market rates, an issuer that invested proceeds freely could earn a risk-free spread at the federal government’s expense. The rebate closes that gap.

Rebate Is Not the Same as Yield Restriction

Federal arbitrage rules impose two separate constraints, and they get confused constantly. Yield restriction prohibits investing bond proceeds in anything that earns materially more than the bond yield in the first place. Rebate applies to any excess earnings that do accumulate on nonpurpose investments and requires the issuer to pay them over.² A rebate payment often satisfies yield restriction as well, but not always. An issuer can owe a yield reduction payment when no rebate is due, or the other way around.

Temporary periods give issuers breathing room. Capital project proceeds generally have three years to be spent above the bond yield without violating yield restriction; substantial construction backed by an architect’s or engineer’s certification extends that to five years. Working capital proceeds get 13 months, and replacement proceeds usually get 30 days.³ Once the temporary period ends, unspent proceeds must be yield-restricted, or the issuer can make a yield reduction payment that effectively brings the investment yield down for compliance purposes. Yield reduction payments are available for temporary-period proceeds, variable yield issues, and reserve fund investments, and they use the same form and timing as rebate payments.⁴

How the Rebate Amount Is Calculated

The calculation compares two numbers: what nonpurpose investments actually earned, and what they would have earned at exactly the bond yield. The difference is the rebate. In the regulatory formula, it equals the future value of all receipts on nonpurpose investments minus the future value of all payments, with both sides compounded forward to the computation date at the bond yield.⁵

Every investment purchase, sale, maturity, interest payment, and dividend gets a date stamp and is compounded at the bond yield to the computation date. The bond yield for a fixed-rate issue is the discount rate that equates the present value of scheduled principal, interest, and qualified guarantee fee payments with the issue price on the issue date.⁶ Refundings, variable-rate debt, and multiple funds make the math substantially harder.

Commingling is where most calculation errors come from. Many issuers deposit bond proceeds into the same bank accounts or investment pools they use for general operating money. The regulations treat amounts flowing into and out of a commingled fund as payments and receipts for rebate purposes, and earnings must be allocated between bond proceeds and other money.⁷ Sloppy allocation here quietly inflates or understates the rebate.

Filing Deadlines and Form 8038-T

Rebate payments follow a fixed schedule. The issuer must make an installment at least once every five years from the issue date, and each installment must cover at least 90 percent of the cumulative rebate calculated as of that date, net of previous payments.¹ The final payment, covering everything still owed, is due within 60 days after the last bond in the issue is redeemed.⁶

All payments go on IRS Form 8038-T, which also covers yield reduction payments and penalties in lieu of rebate.⁸ The form asks for issuer and issue identification, the computation period, and the payment amount. It is mailed with payment to the Internal Revenue Service Center in Ogden, UT 84201-0027.⁹

What You Need to Run the Calculation

The calculation runs on documents. You need the official statement and tax certificate from closing, which fix the bond yield and the rules for investing proceeds. You need investment statements showing every purchase, sale, maturity, and earning on each account holding proceeds. You need expenditure records — invoices, requisitions, check registers, draw schedules — to show when proceeds left the calculation. And for commingled funds you need allocation records showing which share of each balance represents bond proceeds. Missing months of investment activity typically force conservative assumptions that inflate the rebate.

Record Retention

The IRS expects issuers to retain all material records related to a tax-exempt bond issue for as long as the bonds are outstanding, plus three years after final redemption.¹⁰ For a 30-year bond, that runs 33 years or more. The retention covers closing documents, investment statements, the rebate calculations, and every Form 8038-T filed against the issue.

Exceptions That Eliminate the Rebate

Not every issue owes rebate. Two categories of exceptions can take it off the table entirely.

Spend-Down Exceptions

If proceeds are spent quickly, the issue can avoid rebate. There are three timelines, and missing any milestone within a chosen exception disqualifies the issue from that exception.

The six-month exception requires spending all gross proceeds within six months of issuance. Amounts in a bona fide debt service fund are excluded from the spending test.¹¹

The eighteen-month exception uses a tiered schedule from the issue date:

At least 15 percent of gross proceeds spent within 6 months
At least 60 percent spent within 12 months
100 percent spent within 18 months

Bona fide debt service fund earnings are again excluded.¹¹

The two-year construction exception has the most generous timeline, measured in six-month steps:

At least 10 percent of available construction proceeds spent within 6 months
At least 45 percent within 1 year
At least 75 percent within 18 months
100 percent within 2 years

If a construction issue misses one of these benchmarks, the issuer can still avoid a full rebate by electing a penalty in lieu of rebate equal to 1.5 percent of the unspent construction proceeds as of that deadline.¹² For a project that hits delays, the penalty is often much cheaper than the full rebate would be.¹

Small Issuer Exception

A smaller governmental issuer can avoid rebate entirely if all four conditions are met: it has general taxing powers, none of the bonds are private activity bonds, at least 95 percent of net proceeds fund local governmental activities, and it does not reasonably expect to issue more than $5 million in tax-exempt bonds during the calendar year. For bonds financing public school construction, the $5 million ceiling rises by the lesser of $10 million or the amount attributable to school facilities, effectively allowing up to $15 million for a qualifying school district.¹ Qualifying issuers should still keep detailed records proving eligibility, because the IRS can challenge the exception years later on audit.

SLGS as a Compliance Tool

State and Local Government Series securities are special non-marketable Treasuries available only to state and local governments, created by the Treasury in 1972 to help issuers stay inside the yield restriction and rebate rules. Time Deposit SLGS pay a maximum rate set one basis point below the comparable Treasury rate, which keeps the investment yield safely below the trigger. Demand Deposit SLGS are one-day instruments that roll over automatically at a rate tied to the most recent 13-week Treasury bill auction.¹³ Treasury periodically suspends SLGS sales near the federal debt ceiling; during suspensions, issuers must use alternative investments and may be eligible to make yield reduction payments to cure any resulting yield problem.⁴

Penalties for Missing the Requirement

An issuer that misses a rebate deadline or underpays faces a penalty of 50 percent of the unpaid rebate amount plus interest for governmental and qualified 501(c)(3) bonds. For other bonds, the penalty is 100 percent of the unpaid amount plus interest.⁹ At the far end, the IRS can declare the bonds taxable retroactively, which forces the issuer to make bondholders whole for the lost tax benefit.

Waiver for Late Payment

The penalty can be waived if the failure was not due to willful neglect and the issuer pays the full rebate plus interest within 180 days of discovering the miss. An explanation of the failure and why it was not willful must be attached to the Form 8038-T.⁹ The valve only works for issuers who catch the problem and act on it.

Voluntary Closing Agreement Program

For more serious failures, the Tax Exempt Bonds Voluntary Closing Agreement Program lets an issuer come forward and negotiate a resolution before an audit surfaces the problem. Through VCAP, the issuer signs a closing agreement with the IRS that conclusively resolves the violation, though the agreement cannot cover future events or ongoing compliance.¹⁴ Self-reporting through VCAP typically produces a better outcome than letting an examination find the issue first.

1
Office of the Law Revision Counsel. 26 USC 148 – Arbitrage
2
Internal Revenue Service. Tax Exempt Bonds Phase II – Lesson 1, Review of Arbitrage and Rebate
3
eCFR. 26 CFR 1.148-2 – General Arbitrage Yield Restriction Rules
4
eCFR. 26 CFR 1.148-5 – Yield and Valuation of Investments
5
GovInfo. 26 CFR 1.148-3 – General Arbitrage Rebate Rules
6
Internal Revenue Service. Arbitrage and Rebate
7
eCFR. 26 CFR 1.148-3 – General Arbitrage Rebate Rules
8
Internal Revenue Service. About Form 8038-T, Arbitrage Rebate, Yield Reduction and Penalty in Lieu of Arbitrage Rebate
9
Internal Revenue Service. Instructions for Form 8038-T
10
Internal Revenue Service. Tax Exempt Bond FAQs Regarding Record Retention Requirements
11
eCFR. 26 CFR 1.148-7 – Spending Exceptions to the Rebate Requirement
12
Internal Revenue Service. Instructions for Form 8038-T
13
TreasuryDirect. About the State and Local Government Series (SLGS) Securities
14
Internal Revenue Service. TEB Voluntary Closing Agreement Program