# Otter Tail Corp: filings

OTTR · Nasdaq · CIK 1466593 · [Utilities](/sectors/utilities.md) · fiscal year ends Dec 31

Pages: [Overview](/companies/ottr.md) · [Financials](/companies/ottr/financials.md) · [Filings](/companies/ottr/filings.md) · [Insiders](/companies/ottr/insiders.md)

## Reports and events: 275 filings

Newest first, by EDGAR acceptance time (Eastern). Filter with ?form= one of: `periodic`, `8-K`, `10-K`, `10-Q`, `4`, `proxy`, `13dg`, `all`, or any form this company filed (4 460, 8-K 173, 10-Q 52, SC 13G/A 22, 3 18, 10-K 17, DEF 14A 17, SD 13, ARS 10, S-3ASR 10, SC 13D/A 10, S-8 POS 8, UPLOAD 8, 424B5 6, DEFA14A 6, 5 5, CORRESP 5, CT ORDER 5, 144 4, S-8 4, 10-K/A 3, POSASR 3, 8-K/A 2, PRE 14A 2, SCHEDULE 13G 2, 10-Q/A 1, 15-12G 1, 3/A 1, 424B2 1, 4/A 1, 8-K12G3 1, DEFR14A 1, FWP 1, SC 13G 1, SCHEDULE 13G/A 1).

| Filed | Accepted | Form | What it is | Accession |
| --- | --- | --- | --- | --- |
| 2026-09-01 | 09:58 ET | [8-K](/filings/0001466593-26-000074.md) | 5.02 Departure or appointment of officers or directors | 0001466593-26-000074 |
| 2026-08-05 | 12:58 ET | [10-Q](/filings/0001466593-26-000071.md) | Quarterly report, period 2026-06-30 | 0001466593-26-000071 |
| 2026-08-04 | 08:29 ET | [8-K](/filings/0001466593-26-000068.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0001466593-26-000068 |
| 2026-06-18 | 08:02 ET | [8-K](/filings/0001466593-26-000063.md) | 1.01 Entry into a material agreement | 0001466593-26-000063 |
| 2026-06-05 | 09:52 ET | [8-K](/filings/0001466593-26-000061.md) | 2.03 New direct financial obligation | 0001466593-26-000061 |
| 2026-05-29 | 10:47 ET | [8-K](/filings/0001466593-26-000057.md) | 1.01 Entry into a material agreement | 0001466593-26-000057 |
| 2026-05-15 | 13:57 ET | [8-K](/filings/0001466593-26-000054.md) | 8.01 Other events | 0001466593-26-000054 |
| 2026-05-06 | 13:17 ET | [10-Q](/filings/0001466593-26-000051.md) | Quarterly report, period 2026-03-31 | 0001466593-26-000051 |
| 2026-05-05 | 09:16 ET | [8-K](/filings/0001466593-26-000049.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0001466593-26-000049 |
| 2026-04-15 | 10:04 ET | [8-K](/filings/0001466593-26-000040.md) | 5.07 Shareholder vote results | 0001466593-26-000040 |
| 2026-04-14 | 14:32 ET | [8-K](/filings/0001466593-26-000037.md) | 5.02 Departure or appointment of officers or directors; 7.01 Regulation FD disclosure; 9.01 Financial statements and exhibits | 0001466593-26-000037 |
| 2026-03-23 | 09:40 ET | [8-K](/filings/0001466593-26-000034.md) | 1.01 Entry into a material agreement; 2.03 New direct financial obligation; 9.01 Financial statements and exhibits | 0001466593-26-000034 |
| 2026-03-02 | 10:15 ET | [DEF 14A](/filings/0001466593-26-000023.md) | Proxy statement, period 2026-04-13 | 0001466593-26-000023 |
| 2026-02-23 | 16:03 ET | [10-K/A](/filings/0001466593-26-000015.md) | Annual report, amended, period 2025-12-31 | 0001466593-26-000015 |
| 2026-02-18 | 13:27 ET | [10-K](/filings/0001466593-26-000008.md) | Annual report, period 2025-12-31 | 0001466593-26-000008 |
| 2026-02-17 | 09:18 ET | [8-K](/filings/0001466593-26-000002.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0001466593-26-000002 |
| 2025-12-18 | 09:16 ET | [8-K](/filings/0001466593-25-000128.md) | 5.02 Departure or appointment of officers or directors; 7.01 Regulation FD disclosure; 9.01 Financial statements and exhibits | 0001466593-25-000128 |
| 2025-11-05 | 16:19 ET | [10-Q](/filings/0001466593-25-000122.md) | Quarterly report, period 2025-09-30 | 0001466593-25-000122 |
| 2025-11-04 | 09:23 ET | [8-K](/filings/0001466593-25-000119.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0001466593-25-000119 |
| 2025-08-06 | 13:54 ET | [10-Q](/filings/0001466593-25-000107.md) | Quarterly report, period 2025-06-30 | 0001466593-25-000107 |
| 2025-08-05 | 09:20 ET | [8-K](/filings/0001466593-25-000102.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0001466593-25-000102 |
| 2025-06-06 | 09:34 ET | [8-K](/filings/0001466593-25-000097.md) | 2.03 New direct financial obligation | 0001466593-25-000097 |
| 2025-06-05 | 09:58 ET | [8-K](/filings/0001466593-25-000091.md) | 8.01 Other events | 0001466593-25-000091 |
| 2025-05-07 | 12:13 ET | [10-Q](/filings/0001466593-25-000083.md) | Quarterly report, period 2025-03-31 | 0001466593-25-000083 |
| 2025-05-06 | 08:28 ET | [8-K](/filings/0001466593-25-000080.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0001466593-25-000080 |
| 2025-04-17 | 10:17 ET | [8-K](/filings/0001466593-25-000075.md) | 5.07 Shareholder vote results | 0001466593-25-000075 |
| 2025-03-31 | 10:31 ET | [8-K](/filings/0001466593-25-000054.md) | 1.01 Entry into a material agreement; 2.03 New direct financial obligation; 9.01 Financial statements and exhibits | 0001466593-25-000054 |
| 2025-03-03 | 09:27 ET | [DEF 14A](/filings/0001466593-25-000049.md) | Proxy statement, period 2024-12-31 | 0001466593-25-000049 |
| 2025-02-19 | 15:09 ET | [10-K](/filings/0001466593-25-000034.md) | Annual report, period 2024-12-31 | 0001466593-25-000034 |
| 2025-02-18 | 08:34 ET | [8-K](/filings/0001466593-25-000027.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0001466593-25-000027 |
| 2024-12-31 | 15:09 ET | [8-K](/filings/0001466593-24-000149.md) | 8.01 Other events | 0001466593-24-000149 |
| 2024-12-16 | 15:23 ET | [8-K](/filings/0001466593-24-000147.md) | 1.01 Entry into a material agreement; 2.03 New direct financial obligation; 9.01 Financial statements and exhibits | 0001466593-24-000147 |
| 2024-11-07 | 12:30 ET | [10-Q](/filings/0001466593-24-000140.md) | Quarterly report, period 2024-09-30 | 0001466593-24-000140 |
| 2024-11-05 | 08:36 ET | [8-K](/filings/0001466593-24-000136.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0001466593-24-000136 |
| 2024-10-03 | 16:15 ET | [SC 13D/A](/filings/0001104659-24-105851.md) | Ownership report, active investor, amended | 0001104659-24-105851 |
| 2024-08-07 | 12:48 ET | [10-Q](/filings/0001466593-24-000129.md) | Quarterly report, period 2024-06-30 | 0001466593-24-000129 |
| 2024-08-06 | 09:15 ET | [8-K](/filings/0001466593-24-000125.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0001466593-24-000125 |
| 2024-06-05 | 10:48 ET | [8-K](/filings/0001466593-24-000121.md) | 8.01 Other events | 0001466593-24-000121 |
| 2024-05-08 | 15:37 ET | [10-Q](/filings/0001466593-24-000113.md) | Quarterly report, period 2024-03-31 | 0001466593-24-000113 |
| 2024-05-07 | 09:21 ET | [8-K](/filings/0001466593-24-000109.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0001466593-24-000109 |
| 2024-04-10 | 10:03 ET | [8-K](/filings/0001466593-24-000085.md) | 5.07 Shareholder vote results | 0001466593-24-000085 |
| 2024-04-05 | 08:58 ET | [8-K](/filings/0001466593-24-000064.md) | 8.01 Other events | 0001466593-24-000064 |
| 2024-04-02 | 09:55 ET | [8-K](/filings/0001466593-24-000061.md) | 1.01 Entry into a material agreement; 2.03 New direct financial obligation | 0001466593-24-000061 |
| 2024-02-28 | 09:11 ET | [DEF 14A](/filings/0001466593-24-000055.md) | Proxy statement, period 2023-12-31 | 0001466593-24-000055 |
| 2024-02-14 | 16:05 ET | [10-K](/filings/0001466593-24-000039.md) | Annual report, period 2023-12-31 | 0001466593-24-000039 |
| 2024-02-13 | 09:11 ET | [8-K](/filings/0001466593-24-000034.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0001466593-24-000034 |
| 2024-01-29 | 09:26 ET | [8-K](/filings/0001466593-24-000010.md) | 5.02 Departure or appointment of officers or directors | 0001466593-24-000010 |
| 2023-12-21 | 12:59 ET | [8-K](/filings/0001466593-23-000165.md) | 8.01 Other events | 0001466593-23-000165 |
| 2023-11-03 | 13:13 ET | [10-Q](/filings/0001466593-23-000161.md) | Quarterly report, period 2023-09-30 | 0001466593-23-000161 |
| 2023-10-31 | 09:26 ET | [8-K](/filings/0001466593-23-000159.md) | 2.02 Results of operations; 9.01 Financial statements and exhibits | 0001466593-23-000159 |

Page 1 of 6. [Older](/companies/ottr/filings.md?page=2)
Source: SEC EDGAR, the company’s filing index. Last ingested by Listed: Oct 24, 2026, 15:08 ET. No prices; not investment advice.