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: Wahlund Todd R (Chief Financial Officer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2026-02-06	Common Stock	M	675	—	Acquired	10148	Direct
2026-02-06	Common Stock	F	119	$87.83	Disposed	10029	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2026-02-06	Restricted Stock Units	$	M	300	Disposed		Common Stock (600)	Direct
2026-02-06	Restricted Stock Units	$	M	375	Disposed		Common Stock (1125)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	7	Indirect
Common Stock	3048	Indirect

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Restricted Stock Units	$		Common Stock (460)	460	Direct
Restricted Stock Units	$		Common Stock (600)	600	Direct

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 through the dividend reinvestment plan, the Employee Stock Purchase Plan, and shares acquired pursuant to restricted stock unit distributions.

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

F5: Restricted stock units vest four years from date shown above.