424B5 1 rli-20260225x424b5.htm 424B5

Filed Pursuant to Rule 424(B)(5)

Registration No. 333-293622

The information in this preliminary prospectus supplement is not complete and may be changed. This preliminary prospectus supplement and the accompanying prospectus are not offers to sell these securities and are not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

Subject to completion, dated February 26, 2026

Preliminary Prospectus Supplement

(To Prospectus dated February 20, 2026)

% Senior Notes due 2036

RLI Corp. (“RLI”) is offering $ of its % Senior Notes due 2036 (the “Notes”). The Notes will bear interest at the rate of % per year. Interest on the Notes is payable on and of each year, beginning , 2026. The Notes will mature on , 2036. RLI may redeem some or all of the Notes at any time and from time to time at the applicable redemption prices discussed under the caption “Description of Notes—Optional Redemption.” The Notes will be issued only in registered form in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof.

The Notes will be unsecured and rank equally in right of payment with all of RLI’s other unsecured and unsubordinated indebtedness outstanding from time to time.

The Notes are new issues of securities with no established trading market. The Notes will not be listed on any securities exchange or on any automated dealer quotation system.

Investing in the Notes involves risks. See “Risk Factors” beginning on Page S-7 and the “Risk Factors” section in our Annual Report on Form 10-K for the year ended December 31, 2025 for important factors you should consider before buying the Notes.

Neither the Securities and Exchange Commission (the “SEC”) nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

		Per note			Total
Public offering price⁽¹⁾		—	%	$	—
Underwriting discount		—	%	$	—
Proceeds, before expenses, to RLI⁽¹⁾		—	%	$	—

(1) Plus accrued interest, if any, from , 2026 to date of delivery.

The underwriters expect to deliver the Notes to purchasers through the book-entry delivery system of The Depository Trust Company for the accounts of its participants, including Clearstream Banking S.A. and Euroclear Bank SA/NV, on or about , 2026, which will be the business day following the date of the pricing of the notes (such settlement being referred to as “T+ ”) against payment in immediately available funds.

Joint Book-Running Managers

BofA Securities		PNC Capital Markets LLC

February , 2026


	Page

Prospectus Supplement

About This Prospectus Supplement	S-ii
Forward-Looking Statements	S-ii
Prospectus Supplement Summary	S-1
Risk Factors	S-7
Use of Proceeds	S-9
Capitalization	S-10
Description of Notes	S-11
Book-Entry Delivery and Settlement	S-14
Certain Tax Consequences	S-18
Underwriting	S-22
Legal Matters	S-26
Experts	S-26

Prospectus

About This Prospectus	ii
Forward-Looking Statements	iii
RLI Corp.	1
Risk Factors	2
Use of Proceeds	3
Description of the Debt Securities	4
Plan of Distribution	18
Where You Can Find More Information	21
Incorporation of Certain Information by Reference	22
Legal Matters	23
Experts	24


Issuer	RLI Corp.
Securities Offered	$ aggregate principal amount of % senior notes due 2036.
Maturity	, 2036.
Interest Rate	The Notes will bear interest at a rate of % per annum.
Interest Payment Dates	Interest is payable semi-annually on and of each year, beginning , 2026.
Ranking	The Notes will be senior unsecured obligations of RLI and will rank equally in right of payment with all of RLI’s other unsecured and unsubordinated indebtedness outstanding from time to time. The Notes will be structurally subordinated to all obligations of RLI’s subsidiaries, including claims with respect to trade payables. As of December 31, 2025, we had no outstanding secured indebtedness. As of December 31, 2025, we had approximately $50 million of unsecured indebtedness outstanding (other than trade payables), and $50 million of subsidiary indebtedness, and therefore $50 million of subsidiary indebtedness would be structurally senior to the Notes.
Optional Redemption	Prior to , 20 (the date that is months prior to the scheduled maturity of the Notes) (the “Par Call Date”), we may redeem some or all of the Notes at our option at any time and from time to time at the make-whole redemption price, as described in “Description of the Notes—Optional Redemption.” On or after the Par Call Date, we may redeem some or all of the Notes at our option at any time and from time to time at a redemption price equal to 100% of the principal amount of the Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the date of redemption.

Covenants	The indenture under which we will issue the Notes contains covenants that, among other things, limit our ability to (1) dispose of, or incur indebtedness secured by, the capital stock of designated subsidiaries and (2) engage in mergers, consolidations, amalgamations and sales of all or substantially all of our assets. See “Description of the Debt Securities—Certain Covenants With Respect To Senior Debt Securities” and “—Consolidation, Amalgamation, Merger and Sale of Assets” in the accompanying prospectus.
Use of Proceeds	We intend to use the net proceeds from this offering for general corporate purposes. See “Use of Proceeds.”
Form and Denomination	We will issue the Notes in the form of one or more fully registered global securities registered in the name of the nominee of The Depository Trust Company (“DTC”). Beneficial interests in the Notes will be represented through book-entry accounts of financial institutions acting on behalf of beneficial owners as direct and indirect participants in DTC. Clearstream Banking S.A. and Euroclear Bank SA/NV, as operator of the Euroclear System, will hold interests on behalf of their participants through their respective U.S. depositaries, which in turn will hold such interests in accounts as participants of DTC. Except in the limited circumstances described in this prospectus supplement, owners of beneficial interests in the Notes will not be entitled to have Notes registered in their names, will not receive or be entitled to receive Notes in definitive form and will not be considered holders of Notes under the indenture. The Notes will be issued only in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof.
Governing Law	New York.
Trustee, Paying Agent and Security Registrar	Computershare Trust Company, N.A.
Risk Factors	Before making an investment decision, you should carefully consider all of the information included or incorporated or deemed incorporated by reference in this prospectus supplement and the accompanying prospectus, including the information described under, or incorporated by reference into, “Risk Factors” beginning on page S-7 of this prospectus supplement.


		At December 31, 2025
		(in thousands)
			Actual			As adjusted
Cash		$	51,565		$
Short-term investments, at cost which approximates fair value			120,562			120,562
Short-term debt⁽¹⁾		$	100,000		$	100,000
Long-term debt:
Notes offered hereby		$	—		$
Total long-term indebtedness		$	—		$
Shareholders’ equity
Common stock, par value $0.01 per share		$	1,377		$	1,377
Paid-in capital			376,679			376,679
Accumulated other comprehensive earnings			(88,074)			(88,074)
Retained earnings			1,881,213			1,881,213
Deferred compensation			14,082			14,082
Treasury shares, at cost			(407,081)			(407,081)
Total shareholders’ equity			1,778,196			1,778,196
Total capitalization		$	1,878,196		$

Underwriter		Principal Amount of Notes
BofA Securities, Inc.	$	—
PNC Capital Markets LLC		—
Total:	$	—

SEC Form 424B5 filed by RLI Corp.