AMENTUM CLEAN ENERGY LIMITED

Active
Company number 01120437Private limited companyIncorporated 1973
⚠ Accounts overdue. The next accounts were due on 30 Sep 2026 and had not been filed when the register was last updated.

Key figures

£80,577,000+225.1%
Net assets 2023/24
+225.1%
Average annual growth 2022/23–2023/24
025 m50 m75 m100 m2022/232023/24

† AMENTUM CLEAN ENERGY LIMITED filed these accounts on paper, so Companies House publishes them only as a scanned image. The figures for the years marked † were read automatically from the scan and kept only where the statements add up (for example net assets equal total equity), but a reading error is still possible — check the original accounts at Companies House.

Ratios

2023/24

Sector comparison

SIC 42220

Where the company stands among the 3,617 active companies whose first SIC code is 42220 (Construction of utility projects for electricity and telecommunications).

Turnover£554,399,000
Higher than 98% · median £1,632,521 among 137 that publish turnover
Net assets£80,577,000
Higher than 99% · median £16,276
Total assets£253,028,000
Higher than 99% · median £68,983
Cash£50,207,000
Higher than 99% · median £23,818
Employees2,519
Higher than 99% · median 1
Company age53.4 years
Older than 99% · median 3.7 years

Positions are approximate. Figures come from each company's latest accounts; money and employee figures are compared only with companies that filed accounts in pounds for a period ending in the last two and a half years and are not dormant, so those groups are smaller than 3,617. The line on each bar marks the median.

Summary: AMENTUM CLEAN ENERGY LIMITED

What kind of company is it?

AMENTUM CLEAN ENERGY LIMITED is a private limited company registered with Companies House under company number 01120437. It was incorporated on 28 Jun 1973. Its status is active. The registered office is in Warrington (WA3). Its nature of business (SIC 2007) is construction of utility projects for electricity and telecommunications (42220), engineering design activities for industrial process and production (71121), engineering related scientific and technical consulting activities (71122), technical testing and analysis (71200).

How is the company doing financially?

The latest accounts in the database are for 2023/24 (period ending 27 Sep 2024); the company files full accounts. Turnover was £554,399,000. Loss for the year was £222,000. Net assets were £80,577,000, up 225.1% on the previous year. Cash at bank and in hand was £50,207,000. The company had an average of 2,519 employees. Figures are available for 2 financial years (2022/23–2023/24).

How does it compare with similar companies?

Compared with 3,617 active companies whose first SIC code is 42220: By turnover it ranks higher than 98% of the 137 that publish turnover (median £1,632,521). By net assets it ranks higher than 99% of them (median £16,276). By total assets it ranks higher than 99% of them (median £68,983). By cash it ranks higher than 99% of them (median £23,818). By number of employees it ranks higher than 99% of them (median 1). It is older than 99% of them (median age 3.7 years).

Does it supply the public sector?

The company is named as a supplier in 263 public contract award notices from 44 public sector buyers since 2015. Contracts awarded to it alone have a combined published value of £949.9m. Its most frequent buyer is RADIOACTIVE WASTE MANAGEMENT LIMITED (119 contracts). 48 of the awards are shared with other suppliers, typically framework agreements. It is recorded as the recipient of 4 central government grants worth £237.7k, mainly from Department for Business, Energy and Industrial Strategy.

What do public registers and reports show?

HMRC lists it as an importer of goods, mainly machinery, electrical equipment, optical, medical and measuring instruments. HMRC lists it as an exporter of goods, mainly machinery, electrical equipment. In its latest payment practices report it took an average of 27 days to pay suppliers, and 18% of invoices were not paid within agreed terms. Its gender pay gap report for 2025/26 shows median hourly pay for women 22.1% lower than for men. It has modern slavery statements on the government registry for 4 years.

Who runs and controls the company?

One person with significant control is registered. 1 of 2 registered charges are outstanding.

When are its next filings due?

The next accounts are due by 30 Sep 2026. The next confirmation statement is due by 24 Apr 2027.

Filed accounts2022/23–2023/24
2022/23 †2023/24 †
Turnover303,675,000554,399,000
Profit for the year8,772,000-222,000
Cash at bank and in hand25,194,00050,207,000
Total assets118,457,000253,028,000
Total liabilities——
Net assets / total equity24,787,00080,577,000
Average number of employees1,4122,519

A dash (—) means no accounts were filed for that year or the item is not in the accounts; 0 is a zero stated in the accounts. Small companies usually file only a balance sheet, so the profit and loss account is often missing.

Public contracts

263 contracts

AMENTUM CLEAN ENERGY LIMITED is named as a supplier in 263 public contract award notices from 44 public sector buyers since 2015. The 200 contracts awarded to it alone with a published value add up to £949.9m. 48 awards are shared with other suppliers and not counted in that total.

Contracts per year
Main buyers44
RADIOACTIVE WASTE MANAGEMENT LIMITED
119 contracts · £19.6m
United Kingdom Atomic Energy Authority
24 contracts · £8.9m
CTM Portal for the NDA Shared Services Alliance
16 contracts · £781.4m
Sellafield Ltd
10 contracts · £84.7m
Nuclear Decommissioning Authority
10 contracts · £1.3m
Latest 100 contracts
  1. DNWP0068/LOT1A/Calder Breakdowns and Maintenance Resource‡Sellafield Ltd · £597,888 · runs until Mar 2027
  2. Corrosion Testing Framework for STEP‡UK Fusion Energy Ltd · shared by 5 suppliers, up to £6,000,000 in total · 3 lots · runs until Nov 2028
  3. DNWP0072/LOT1A/ THB Demolition Phases 1-5‡Sellafield Limited · £14,848,365 · runs until Sep 2028
  4. Waste Characterisation Support on the Dounreay site.‡Nuclear Restoration Services Limited (Dounreay) · shared by 4 suppliers, up to £3,048,000 in total · runs until Aug 2028
  5. DNWP0071/LOT1A/CALDER Ring Fence‡Sellafield Ltd · £478,697 · runs until May 2027
Show 95 more
  1. DNWP0040/LOT1A/ HEx-1 Laydown area excavation and pour‡Sellafield Ltd · £3,425,940 · runs until May 2028
  2. DNWP0039/LOT1A/Management Team FY26/27‡Sellafield Limited · £4,084,270 · runs until Mar 2027
  3. UVDB Powered by Achilles QUDM for Goods, Works and ServicesAFFINITY WATER LIMITED · shared by 550 suppliers
  4. W2B5 4-point bend: AUK Fusion Energy Ltd · £33,173 · runs until Nov 2026
  5. Open Framework for Nuclear Technical ServicesUNITED KINGDOM NATIONAL NUCLEAR LABORATORY LIMITED · shared by 32 suppliers · 10 lots · runs until Aug 2030
  6. G Cloud 15‡Government Commercial Agency · shared by 2,282 suppliers, up to £14,000,000,000 in total · runs until Aug 2030
  7. GK26-11 - In-active Drying Trials of AGR Slotted Cans (Investigating Impact of Caustic Dosing and Carbon Deposits)‡Nuclear Decommissioning Authority · £360,186 · runs until Jan 2028
  8. DCP Stores Extension - Engineering Support Requirement‡Nuclear Restoration Services Limited · shared by 3 suppliers, up to £275,262 in total
  9. Pd Ag Functional Testing‡UK Fusion Energy Ltd · £195,000 · runs until Mar 2027
  10. DNWP0061/LOT1A/CALDER R1 & R2 Filter Room Full Deplant‡Sellafield Ltd · £184,647 · runs until Jun 2027
  11. CSSF-001 - Support to international post closure criticality safety projects.‡Nuclear Waste Services · shared by 2 suppliers, up to £20,000 in total · runs until Mar 2027
  12. Environmental & Conventional Health & Safety Services‡Sellafield Ltd · shared by 5 suppliers, up to £9,920,000 in total · runs until May 2035
  13. Environmental & Conventional Health & Safety Services‡Sellafield Limited · £9,000,000 · 2 lots
  14. CSSF-002 - GDF Criticality Safety Methodology and Assessments‡Nuclear Waste Services · shared by 2 suppliers, up to £40,000 in total
  15. Prototype Fast Reactor Concrete Panels Methodology‡NRS Dounreay · £93,798 · runs until Dec 2026
  16. Alternative Solutions Bulk Order Further Comp (dummy)‡Nuclear Waste Services · £1,300,000 · runs until Apr 2027
  17. DNWP0053/LOT1A/CALDER F199 Demolition‡Sellafield Ltd · £152,895
  18. BLC-0201 - Cyber Security Services FrameworkBLUELIGHT COMMERCIAL LIMITED · shared by 6 suppliers, up to £16,000,000 in total · 2 lots · runs until May 2034
  19. TECHNICAL SUPPORT PROVIDER (TSP): MUNITIONS (DM) GOSPORT - WATERFRONT MUNITIONS HANDLING FACILITY (WMHF) - BEDENHAM PIERDefence Infrastructure Organisation · £4,500,000 · runs until Apr 2029
  20. Expert Support and Alternative Solutions Framework‡Nuclear Waste Services Limited · £14,500,000
  21. Construction Professional Services 2Government Commercial Agency · shared by 28 suppliers, up to £14,000,000,000 in total · 4 lots · runs until Apr 2030
  22. DNWP0062/LOT1A/ID - Hazard Reduction‡Sellafield Ltd · £1,735,663 · runs until Mar 2027
  23. Owner's EngineerGREAT BRITISH ENERGY - NUCLEAR · shared by 2 suppliers, up to £600,000,000 in total · 2 lots · runs until Apr 2040
  24. CBRN Remediation Services Framework - 2026Department for Environment Food & Rural Affairs · shared by 3 suppliers · runs until Mar 2034
  25. DNWP0056/LOT1A/ Quaternary Borehole Restoration‡Sellafield · £80,736 · runs until Jun 2027
  26. ATO19 D2001 LC15 Peer Review‡Nuclear Restoration Services Limited (Dounreay) · £170,967 · runs until Jun 2027
  27. 959736.70‡Ministry of Defence · shared by 2 suppliers, up to £8,776,588 in total
  28. ThermoChimie Phase 4 FrameworkNuclear Waste Services Limited · shared by 6 suppliers · 3 lots · runs until Mar 2029
  29. Radiological Testing of Nuclear Standard Elastomer to Ensure Continued‡Nuclear Decommissioning Authority
  30. Deterministic Fire Risk Assessment (DFRA) Peer Review‡Nuclear Restoration Services Limited
  31. DNWP0059/LOT1A/Principal Designer Services‡Sellafield Ltd · £499,560
  32. UKRI-5155 Radioactive Waste Characterisation and Treatment Services‡UK Research & Innovation (UKRI) · shared by 3 suppliers, up to £2,500,000 in total · runs until Mar 2030
  33. GK25-12‡Nuclear Decommissioning Authority · £94,689 · runs until Nov 2026
  34. (06 - EDW&MR) DC25-15‡Nuclear Decommissioning Authority · £283,833 · runs until May 2027
  35. Digital Outcomes and Specialists 7Crown Commercial Service · shared by 1,624 suppliers, up to £3,240,000,000 in total · runs until Jul 2027
  36. JDR Management Support Framework.‡UK Atomic Energy Authority · shared by 8 suppliers, up to £8,000,000 in total · runs until Mar 2030
  37. DNWP Framework Digital Client Lead‡Sellafield Ltd · £95,000
  38. Transmission Digital Services Framework‡SCOTTISH HYDRO ELECTRIC TRANSMISSION PLC · runs until Feb 2029
  39. FW Services - Operational Technology Framework‡SCOTTISH HYDRO ELECTRIC TRANSMISSION PLC · runs until Feb 2029
  40. (05 - SF&NM) GK25-13‡Nuclear Decommissioning Authority · £104,246
  41. Technology Services 4Crown Commercial Service · shared by 263 suppliers, up to £16,000,000,000 in total · 9 lots · runs until Jun 2028
  42. Materials Testing Framework for STEPUK Industrial Fusion Solutions Ltd · shared by 3 suppliers, up to £2,333,332 in total · 4 lots · runs until Nov 2027
  43. Decommissioning Nuclear Waste Partnership‡Sellafield Limited · shared by 4 suppliers, up to £4,600,000,000 in total · runs until Oct 2040
  44. Decommissioning Nuclear Waste Partnership (DNWP)‡Sellafield Limited · £1,000,000,000
  45. Post-Closure Safety Case Framework‡Nuclear Waste Services · shared by 5 suppliers · runs until Oct 2029
  46. Post-Closure Safety Case Framework‡Nuclear Waste Services Limited
  47. (04 - SF&NM) GK25-14‡Nuclear Decommissioning Authority · £148,237 · runs until Nov 2026
  48. GK25-15 - Grand Challenges‡Nuclear Decommissioning Authority · £89,194
  49. PFR Raffinate Cement Trials‡NRS Dounreay · £85,878
  50. Contracts for Innovation Competition Fusion Industry Challenges: Novel shielding materials and technologies for fusion‡UK Atomic Energy Authority · shared by 11 suppliers, up to £3,083,562 in total
  51. Integrated Waste Management Specialist Nuclear Services Framework (IWM24)‡Nuclear Waste Services · shared by 8 suppliers, up to £26,000,000 in total · runs until Sep 2029
  52. Integrated Waste Management Specialist Nuclear Services Framework‡Nuclear Waste Services Limited · 4 lots
  53. Incident Planning Operations May & June 2025‡DEPARTMENT OF ENVIRONMENT, FOOD AND RURAL AFFAIRS · £30,791
  54. CBRN Framework Call Off - Incident Planning Operations Sept 2025‡Defra · £20,949
  55. (04 - EDWM&R) IG25-11 - Groupwide Areas of Research Interest‡Nuclear Decommissioning Authority · £57,554
  56. BATS Corrosion on Carbon Steel‡Nuclear Waste Services Limited
  57. Design & Build FrameworkUK Atomic Energy Authority · shared by 12 suppliers, up to £31,666,668 in total · 4 lots
  58. Dounreay Cementation Plant Licence Condition Peer Review‡Nuclear Restoration Services Limited (Dounreay) · £160,052
  59. Simulation Software‡UK Atomic Energy Authority · shared by 10 suppliers, up to £360,000 in total
  60. BATs - Corrosion of Carbon Steel‡Nuclear Waste Services · £260,635
  61. Design of Steelwork Repairs and Ventilation Replacement‡Nuclear Restoration Services Limited (Dounreay) · £112,297
  62. Fully Networked Command, Control and Communications (FNC3)‡MINISTRY OF DEFENCE · £533,121
  63. CBRN Framework Call Off - Incident Planning Operations May & June 2025‡Defra · £30,791
  64. Embedded Engineering Resource Framework (EERF)‡United Kingdom Atomic Energy Authority · shared by 2 suppliers, up to £9,900,000 in total
  65. ESC-L2-TO391A, B & C: Level 2 Report Support‡Nuclear Waste Services · shared by 3 suppliers, up to £329,988 in total
  66. Peer Review Development of Disposal Container Transport Container Sub-Systems‡International Nuclear Services Limited
  67. Production of Licence Condition 15 Periodic Review‡Nuclear Restoration Services Limited (Dounreay) · £802,365
  68. Senior Design Engineer Support‡Nuclear Restoration Services Limited (Dounreay) · £839,918 · runs until Feb 2028
  69. SBRI Competition Fusion Industry Challenges - Novel Concepts for Robust Diagnostics Systems, Sensing and Control‡United Kingdom Atomic Energy Authority · shared by 13 suppliers, up to £3,472,864 in total
  70. TO386 Assessment of Selective Trench Retrievals‡Nuclear Waste Services · £86,732
  71. Autonomous Data Collection‡United Kingdom Atomic Energy Authority · £76,500
  72. TO381 PFLOTRAN Stage 3‡Nuclear Waste Services · £295,356
  73. GB-Harwell: UKRI-4367 Waste Characterisation Service‡UK Research & Innovation · £89,939
  74. KBS/0124/T/MCS1/NK The KBS Multi Discipline Subcontractor Framework 2024KBS MARITIME LIMITED · shared by 35 suppliers, up to £60,000,000 in total
  75. Particle Detector Radiation TestingNATIONAL NUCLEAR LABORATORY LIMITED · £29,801
  76. Fusion Futures: Uncertainty Quantification for Plasma Control Systems‡United Kingdom Atomic Energy Authority · £149,236
  77. Sub-Millimetre Laser Profiling System with Embedded Positional Correction for Defect Monitoring in 500L DrumsNATIONAL NUCLEAR LABORATORY LIMITED · £85,332
  78. Gravity Offload SystemSATELLITE APPLICATIONS CATAPULT LIMITED · £303,000
  79. Engineering Design Services Framework‡United Kingdom Atomic Energy Authority · £7,500,000 · 5 lots
  80. Radioactive Substances Regulation - Ad-hoc Monitoring and Technical Support Framework‡Environment Agency · shared by 7 suppliers, up to £1,500,000 in total · runs until Mar 2028
  81. Radioactive Substances Regulation - Ad-hoc Monitoring and Technical Support Framework‡ENVIRONMENT AGENCY (Defra Network eTendering Portal) · 2 lots
  82. Waste Characterisation‡United Kingdom Atomic Energy Authority · £87,345
  83. For Transparency Purposes JSP 375 chapter reviewMinistry of Defence · £95,000
  84. Safety Case Support and Peer Review Services Framework‡Dounreay Site Restoration Limited (DSRL) · shared by 5 suppliers, up to £8,000,000 in total
  85. Framework Agreement for the Provision of Safety Case Support and Peer Review Services‡Dounreay Site Restoration Limited
  86. ACC6036832 - DASA Themed Call: Disruptive Science and Technology Impacting the Future of Defence (Phase 1)Defence Science and Technology Laboratory · £50,000
  87. FOR TRANSPARENCY PURPOSES ONLY - Provision of DTA Noise Audit‡Ministry of Defence · £126,000
  88. Provision of DTA Noise Audit‡Ministry of Defence · £126,000
  89. WP3.5.1 - Development of Datasets for Machine Learning - LongOps‡United Kingdom Atomic Energy Authority · £254,958
  90. WP3.5.2 Novel Techniques and Technologies for Incorporating Sensor Data into Digital Twins‡United Kingdom Atomic Energy Authority · £239,889
  91. Trials work to determine suitability of alternative powders for Intermediate Level Waste (ILW) immobilisation‡CTM Portal for the NDA Shared Services Alliance · £61,676
  92. Update to RSBTC Contents Specification Documents (RWM212-02-006)‡RADIOACTIVE WASTE MANAGEMENT LIMITED · £82,101
  93. UK SBS - PS21316 - Collector VCS0 leak repair at RAL‡UK SHARED BUSINESS SERVICES LIMITED · £13,900
  94. RE21689‡UK SHARED BUSINESS SERVICES LIMITED · £13,890
  95. Waste Characterisation Support‡CTM Portal for the NDA Shared Services Alliance · £327,387

From contract award notices on Contracts Finder (since 2016) and Find a Tender (since 2021), published by the Cabinet Office under the Open Government Licence v3.0. Values are as published by the buyer and usually cover the whole contract term; the total leaves out awards shared between several suppliers, where the published figure is a ceiling for all of them, placeholder values and single figures of £1 billion or more. Notices marked ‡ do not state a company number and were linked by an exact match on the registered name. Contracts below the publication thresholds and those of devolved buyers that publish elsewhere are not included.

Government grants

4 grants

AMENTUM CLEAN ENERGY LIMITED is recorded as the recipient of 4 central government grants since 2020, together worth £237.7k.

Funders
Department for Business, Energy and Industrial Strategy
3 grants · £134.7k
Department for Science, Innovation and Technology
1 grant · £103k
Grants
  1. Development of Very Low Head Tidal TurbineDepartment for Science, Innovation and Technology · £103,001 · UKRI - Innovate UK - Scheme
  2. Low Cost Nuclear Phase 1Department for Business, Energy and Industrial Strategy · −£763 · UKRI - ISCF - Scheme 22/23
  3. SegwaysteDepartment for Business, Energy and Industrial Strategy · £59,711 · ALB - UKRI - Innovate UK grant awards in 20-21
  4. Social Distancing for IndustryDepartment for Business, Energy and Industrial Strategy · £74,980 · ALB - UKRI - Innovate UK grant awards in 20-21

From the Government Grants Register published by the Cabinet Office (financial years 2016/17 onwards, Open Government Licence v3.0). It covers grants from central government departments and their agencies where the register states the recipient's company number and the recipient name matches this company; grants from local authorities, lottery distributors and devolved governments are not included.

Statutory reporting

Payment practices1 Oct 2024 – 31 Mar 2025
Average time taken to pay invoices
27 days
Invoices not paid within agreed terms
18%
Standard payment terms
7–60 days
Member of a payment code
No
  • Within 30 days 82%
  • 31 to 60 days 13%
  • After 60 days 5%
Earlier periods (7)
Period ending
Days to pay
Within 30 days
Late
30 Sep 2024
26
86%
13%
31 Mar 2024
28
87%
13%
30 Sep 2023
27
83%
34%
31 Mar 2023
35
77%
36%
30 Sep 2022
28
78%
34%
31 Mar 2022
37
69%
45%
30 Sep 2021
48
58%
51%

View the latest report on GOV.UK

Gender pay gap2025/26
Median hourly pay
women 22.1% lower
Mean hourly pay
women 17.5% lower
Median bonus pay
women 44.4% lower
Employer size
1000 to 4999 employees
Lower pay quarter37.8% womenLower middle28.8% womenUpper middle20.7% womenUpper pay quarter14.8% women
Earlier years (8)
Year
Median hourly pay
Mean hourly pay
2024/25
women 21.9% lower
women 18.8% lower
2023/24
women 18.6% lower
women 13.5% lower
2022/23
women 22.6% lower
women 16.5% lower
2021/22
women 24.5% lower
women 18.8% lower
2020/21
women 21.5% lower
women 20.4% lower
2019/20
women 15.6% lower
women 19.1% lower
2018/19
women 25.4% lower
women 25.8% lower
2017/18
women 31.3% lower
women 24.8% lower

A positive gap means women's average hourly pay is lower than men's across the whole employer; it is not a comparison of pay for the same work. View on the Gender pay gap service

Modern slavery statements4
2024
Statement · summary on GOV.UK · group statement (JACOBS U.K. LIMITED)
2023
Statement · summary on GOV.UK · group statement (JACOBS U.K. LIMITED)
2022
Statement · summary on GOV.UK · group statement (JACOBS U.K. LIMITED)
Earlier years (1)
2021
Statement · summary on GOV.UK · group statement (JACOBS U.K. LIMITED)

Figures the company reported itself to the government's Check payment practices service, Gender pay gap service and Modern slavery statement registry (Open Government Licence v3.0). Only large companies and employers with 250 or more staff have to report, so most companies have nothing here.

Registers and licences

International trade‡

Listed by HMRC as an importer of goods in 9 of the last 12 months on record, most recently August 2026. Main goods: machinery, electrical equipment, optical, medical and measuring instruments, inorganic chemicals and rubber.

Listed by HMRC as an exporter of goods in 2 of the last 12 months on record, most recently July 2026. Main goods: machinery and electrical equipment.

From HMRC's monthly lists of importers and exporters. Traders can ask to be left off the lists, so absence does not mean a company does not trade.

Sources: Charity Commission for England and Wales, Care Quality Commission, Home Office and HM Revenue & Customs, under the Open Government Licence v3.0. Entries marked ‡ come from lists that do not state a company number and were linked by an exact match on the registered name.

History

13 events
  1. Name changed to AMENTUM CLEAN ENERGY LIMITEDPreviously JACOBS CLEAN ENERGY LIMITED
  2. Financial year 2023/24 endedAccounts: turnover £554.4m, net assets £80.6m, 2,519 employees
  3. Energy, Security And Technology Uk Limited registered as a person with significant control
  4. Jacobs U.K. Limited ceased to be a person with significant control
  5. Financial year 2022/23 endedAccounts: turnover £303.7m, net assets £24.8m, 1,412 employees
  6. Name changed to JACOBS CLEAN ENERGY LIMITEDPreviously WOOD NUCLEAR LIMITED
  7. Jacobs U.K. Limited registered as a person with significant control
  8. Wood Nuclear Holdings Limited ceased to be a person with significant control
Earlier events (5)
  1. Name changed to WOOD NUCLEAR LIMITEDPreviously AMEC FOSTER WHEELER NUCLEAR UK LIMITED
  2. Wood Nuclear Holdings Limited registered as a person with significant control
  3. Name changed to AMEC FOSTER WHEELER NUCLEAR UK LIMITEDPreviously AMEC NUCLEAR UK LIMITED
  4. Name changed to AMEC NUCLEAR UK LIMITEDPreviously AMEC NNC LIMITED
  5. Company incorporatedPrivate limited company

Dates as recorded at Companies House: incorporation, name changes, officer appointments and resignations, current and former persons with significant control, and the end of each financial year with figures in the database.