Prolux Systems Ltd
- Company number
- 11643153
- Incorporated
- 25 Oct 20187 years trading
- Registered office
- Herniss Business Park, Halvasso, Longdowns, Cornwall, TR10 9BZ
- Nature of business
- Construction of domestic buildings; Other building completion and finishing
Prolux Systems Ltd is a 7-year-old private limited company registered in Longdowns, company number 11643153, one of the UK's building contractors. Its next accounts are due at Companies House on 31 July 2027, and the CT600 for the period to 31 October 2026 is due at HMRC on 31 October 2027.
Key dates
Worked out from the year end and filing history on the Companies House register.
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Finances
From each year's balance sheet filed at Companies House. Small companies do not have to publish turnover or profit, so these are balance sheet figures.
- Net assets down £62K (-81.6%) on the year before, to -£139K.
- Net assets rose in 2 of 6 year-on-year comparisons on record.
- Current assets of £367K against £472K owed within a year: 0.8 times cover.
- 20 employees on average, up from 14 the year before.
- Balance sheets on record for 7 years, 2019 to 2025.
Net assets by year
| Year end | Net assets | Cash | Current assets | Owed within a year | Employees |
|---|---|---|---|---|---|
| 31 Oct 2025 | -£139K | £162K | £367K | £472K | 20 |
| 31 Oct 2024 | -£76K | £211K | £367K | £363K | 14 |
| 31 Oct 2023 | -£172K | £88K | £258K | 11 | |
| 31 Oct 2022 | -£192K | £29K | £214K | 10 | |
| 31 Oct 2021 | -£52K | £35K | £50K | 6 | |
| 31 Oct 2020 | -£35K | £37K | £24K | 4 | |
| 31 Oct 2019 | -£14K | -£24K | £12K |
Where Prolux Systems Ltd is registered
The registered office is in Longdowns (TR10), in the Cornwall local authority area, South West. Show TR10 9BZ on a map.
Other trade companies in TR10
- Morva Properties LtdProperty developers
- Cornwall Exterior Cleaning LtdCleaning companies
- Granite Coast Property Group LimitedProperty developers
- Saltwater Services and Fabrication LtdMachinery repair and installation
- Salt & Stone Decorating LtdPainters and decorators
- National Charging Solutions LtdElectricians
- SP (Cornwall) LtdProperty developers
- Ironclad Roofing LimitedInstallers
Also registered at this address
4 other companies use the same registered office as Prolux Systems Ltd.
- Ironclad Roofing LimitedInstallers
- NTK Developments (SPV3) LtdProperty developers
- NTK Developments LtdProperty developers
- VR 1844 LimitedProperty developers
What happens if Prolux Systems Ltd files late
Companies House charges an automatic penalty the day after the deadline, and it rises the longer the accounts are late. These are the dates for this company's accounts due on 31 July 2027.
| Companies House | Accounts delivered | Penalty |
|---|---|---|
| Up to 1 month late | 1 Aug 2027 to 31 Aug 2027 | £150 |
| 1 to 3 months late | 1 Sep 2027 to 31 Oct 2027 | £375 |
| 3 to 6 months late | 1 Nov 2027 to 31 Jan 2028 | £750 |
| More than 6 months late | From 1 Feb 2028 | £1,500 |
Penalties double if the accounts were also late the year before.
| HMRC (CT600) | From | Penalty |
|---|---|---|
| 1 day late | 1 Nov 2027 | £200 |
| 3 months late | 31 Jan 2028 | another £200 |
| 6 months late | 30 Apr 2028 | HMRC estimates the tax and adds 10% of the unpaid tax |
| 12 months late | 31 Oct 2028 | another 10% of any unpaid tax |
For returns filed on or after 1 April 2026. Late three times in a row and the £200 penalties become £1,000 each.
Company details
As held on the Companies House register.
- Company number
- 11643153
- Status
- Active
- Company type
- Private limited company
- Incorporated
- 25 October 2018 (7 years ago)
- Registered office
- Herniss Business Park, Halvasso, Longdowns, Cornwall, TR10 9BZ
- Nature of business
- Construction of domestic buildings (SIC 41202)
Other building completion and finishing (SIC 43390) - Year end
- 31 October (accounting reference date)
- Accounts type
- Unaudited abridged
- Last accounts made up to
- 31 October 2025
- Last confirmation statement
- 24 October 2025
Filing notes for building contractors
Building companies often run the Construction Industry Scheme as a contractor, a subcontractor or both. CIS deductions suffered during the year are set against the PAYE bill, and any unrecovered balance at the year end matters when the accounts are drawn up.
Similar companies
Other active building contractors.
Frequently asked questions
When are Prolux Systems Ltd's accounts due?
Prolux Systems Ltd's next accounts are due at Companies House by 31 July 2027 (in 291 days), covering the period to 31 October 2026.
When is Prolux Systems Ltd's CT600 due?
The CT600 for the period to 31 October 2026 is due at HMRC by 31 October 2027, 12 months after the period end. The corporation tax itself is payable earlier, by 1 August 2027.
Is Prolux Systems Ltd still trading?
Prolux Systems Ltd is listed as active on the Companies House register as of 1 Oct 2026. Active means it has not been dissolved or entered insolvency; it does not show whether it is currently taking on work.
What does Prolux Systems Ltd do?
Prolux Systems Ltd is registered under Construction of domestic buildings (SIC 41202); Other building completion and finishing (SIC 43390).
How old is Prolux Systems Ltd?
Prolux Systems Ltd was incorporated on 25 October 2018, 7 years ago.
What is the penalty if Prolux Systems Ltd files its accounts late?
Companies House charges £150 if the accounts are up to 1 month late, £375 up to 3 months, £750 up to 6 months and £1,500 after that, doubled if the previous year's accounts were also late. HMRC charges £200 for a CT600 filed a day late and another £200 at 3 months.
Official records
View Prolux Systems Ltd on Companies House for filed documents, officers and the full history.
Based on the Companies House register (snapshot 1 Oct 2026). Deadlines are worked out from the register and assume a standard accounting period; a change of year end or a short period moves them. This page is general information, not tax or accountancy advice.