| 02/09/24 | 07:05:01 | 2 Sept 2024 | | Total Voting Rights |
| 02/09/24 | 07:00:08 | 2 Sept 2024 | | Transaction in Own Shares |
| 30/08/24 | 07:00:13 | 30 Aug 2024 | | Transaction in Own Shares |
| 29/08/24 | 07:00:06 | 29 Aug 2024 | | Transaction in Own Shares |
| 28/08/24 | 07:00:08 | 28 Aug 2024 | | Transaction in Own Shares |
| 21/08/24 | 07:10:01 | 21 Aug 2024 | | On-market Share Buyback Programme of £10m |
| 21/08/24 | 07:00:04 | 21 Aug 2024 | | Results for the six months ended 30 June 2024 |
| 16/08/24 | 09:30:01 | 16 Aug 2024 | | Costain wins AMP8 framework with Southern Water |
| 08/08/24 | 09:30:00 | 8 Aug 2024 | | Investor Presentation via Investor Meet Company |
| 05/08/24 | 11:18:15 | 5 Aug 2024 | | Change of Registered Office |
| 01/07/24 | 15:26:29 | 1 Jul 2024 | | Block listing Interim Review |
| 26/06/24 | 07:00:14 | 26 Jun 2024 | | Costain JV awarded Southern Water programme |
| 04/06/24 | 14:41:54 | 4 Jun 2024 | | Costain Secures New AMP8 Framework Agreement |
| 03/06/24 | 10:39:55 | 3 Jun 2024 | | Total Voting Rights |
| 23/05/24 | 15:16:43 | 23 May 2024 | | Additional Listing |
| 16/05/24 | 16:10:00 | 16 May 2024 | | Ordinary Share Nominal Value Reduction |
| 16/05/24 | 16:09:40 | 16 May 2024 | | Result of AGM |
| 16/05/24 | 07:00:06 | 16 May 2024 | | AGM Statement |
| 01/05/24 | 10:41:12 | 1 May 2024 | | Total Voting Rights |
| 25/04/24 | 11:41:15 | 25 Apr 2024 | | Scrip Dividend Reference Price |
| 09/04/24 | 16:16:30 | 9 Apr 2024 | | Director/PDMR Shareholding |
| 09/04/24 | 13:32:48 | 9 Apr 2024 | | Director/PDMR Shareholding |
| 09/04/24 | 09:33:40 | 9 Apr 2024 | | Annual Report and Accounts and Notice of 2024 AGM |
| 04/04/24 | 09:55:54 | 4 Apr 2024 | | Additional Listing |
| 15/03/24 | 08:30:01 | 15 Mar 2024 | | Key Partner for Landmark Carbon Capture Project |
| 12/03/24 | 07:01:00 | 12 Mar 2024 | | Directorate Change |
| 12/03/24 | 07:00:07 | 12 Mar 2024 | | 2023 Full Year Results |
| 27/02/24 | 12:06:05 | 27 Feb 2024 | | Investor Presentation via Investor Meet Company |
| 10/01/24 | 07:00:04 | 10 Jan 2024 | | AMP8 Water Framework Win with NWG & Trading Update |
| 02/01/24 | 12:56:30 | 2 Jan 2024 | | Block listing Interim Review |
| 01/11/23 | 12:15:47 | 1 Nov 2023 | | Total Voting Rights |
| 27/10/23 | 13:00:01 | 27 Oct 2023 | | Director/PDMR Shareholding |
| 25/10/23 | 13:00:01 | 25 Oct 2023 | | Additional Listing |
| 19/10/23 | 13:00:01 | 19 Oct 2023 | | Director/PDMR Shareholding |
| 17/10/23 | 07:00:11 | 17 Oct 2023 | | Directorate Change |
| 28/09/23 | 12:00:24 | 28 Sept 2023 | | Scrip Dividend Reference Price |
| 25/09/23 | 07:00:03 | 25 Sept 2023 | | Costain and Ofwat Water Seminar |
| 08/09/23 | 14:26:34 | 8 Sept 2023 | | Block listing Interim Review |
| 06/09/23 | 14:25:00 | 6 Sept 2023 | | Director/PDMR Shareholding |
| 05/09/23 | 07:00:05 | 5 Sept 2023 | | Dividend Declaration |
| 23/08/23 | 07:00:05 | 23 Aug 2023 | | Results for the six months ended 30 June 2023 |
| 16/08/23 | 10:00:01 | 16 Aug 2023 | | Interim Results Investor Q&A |
| 26/07/23 | 07:00:09 | 26 Jul 2023 | | Costain Refinancing of Bank and Bonding Facilities |
| 17/07/23 | 07:00:04 | 17 Jul 2023 | | Costain Announces Key Contract Extension |
| 30/06/23 | 07:00:03 | 30 Jun 2023 | | New Payment Plan with Pension Scheme Trustee |
| 22/06/23 | 10:38:41 | 22 Jun 2023 | | Costain Appointed Magnox Decommissioning Framework |
| 08/06/23 | 16:17:22 | 8 Jun 2023 | | Update Regarding A66 Project |
| 11/05/23 | 16:49:08 | 11 May 2023 | | Result of AGM |
| 11/05/23 | 07:00:04 | 11 May 2023 | | AGM Statement |
| 20/04/23 | 09:40:24 | 20 Apr 2023 | | External Appointment |