Otter Tail Corp — Director's Dealing 2026

Feb 9, 2026

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Otter Tail Corp (OTTR)
CIK: 0001466593
Period of Report: 2026-02-06

Reporting Person: ROGELSTAD TIMOTHY J (Sr VP, Electric Platform)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2026-02-06	Common Stock	M	1625	—	Acquired	57655	Direct
2026-02-06	Common Stock	F	763	$87.83	Disposed	56892	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2026-02-06	Restricted Stock Units	$	M	400	Disposed		Common Stock (0)	Direct
2026-02-06	Restricted Stock Units	$	M	450	Disposed		Common Stock (450)	Direct
2026-02-06	Restricted Stock Units	$	M	350	Disposed		Common Stock (700)	Direct
2026-02-06	Restricted Stock Units	$	M	425	Disposed		Common Stock (1275)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	3337	Indirect

Footnotes

F1: Each restricted stock unit represents a contingent right to receive one share of Otter Tail Corporation stock.

F2: These shares were withheld by the Corporation to pay taxes due upon vesting of this award, exempt pursuant to Rule 16b-3(e).

F3: Total direct holdings include shares acquired individually through dividend reinvestment, Employee Stock Purchase Plan, and acquired pursuant to Restricted Stock Awards and Performance Share Awards.

F4: The restricted stock units vest in four equal annual installments beginning the date shown above.