- Companies
- Specialist contractors
- Slough
- Alter Construction Limited
Alter Construction Limited
- Company number
- 09259137
- Incorporated
- 10 Oct 201412 years trading
- Registered office
- 346A Farnham Road, Slough, Berkshire, SL2 1BT
- Nature of business
- Other specialised construction activities n.e.c.
Alter Construction Limited is a 12-year-old private limited company registered in Slough, company number 09259137, one of 110 specialist construction companies in Slough. Its next accounts are due at Companies House on 31 December 2026, and the CT600 for the period to 31 March 2026 is due at HMRC on 31 March 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 £543 (-153%) on the year before, to -£188.
- Net assets rose in 2 of 8 year-on-year comparisons on record.
- Current assets of £662 against £850 owed within a year: 0.8 times cover.
- 1 employee on average during the year.
- Balance sheets on record for 9 years, 2016 to 2025.
Net assets by year
| Year end | Net assets | Cash | Current assets | Owed within a year | Employees |
|---|---|---|---|---|---|
| 31 Mar 2025 | -£188 | £662 | £850 | 1 | |
| 31 Mar 2024 | £355 | £9,724 | £9,369 | 1 | |
| 31 Mar 2023 | -£520 | £700 | £1,220 | 2 | |
| 31 Mar 2022 | £69 | £5,152 | £5,083 | 2 | |
| 31 Mar 2021 | £667 | £14K | £14K | 2 | |
| 31 Mar 2020 | £1,172 | £8,672 | £7,500 | 2 | |
| 31 Mar 2019 | £661 | £12K | £12K | ||
| 31 Mar 2018 | £1,051 | £8,353 | £7,302 | ||
| 31 Oct 2016 | £1,690 | £2,922 | £1,232 |
Where Alter Construction Limited is registered
The registered office is in Slough (SL2), in the Slough local authority area, South East. Show SL2 1BT on a map.
Other trade companies in SL2
- Selmani&Aj Developments LimitedBuilders
- SMKD LimitedMotor traders
- Sloughcleanings LtdCleaning companies
- Neal LtdBuilders
- J Nomah LtdBuilders
- Eton Motor Group LtdMotor traders
- All Perfect Services LtdBuilders
- Datchet Car Body Shop LtdMechanics and garages
Also registered at this address
8 other companies use the same registered office as Alter Construction Limited.
- Alinmead LimitedMachinery repair and installation
- Barley Close Developments LimitedProperty developers
- E.M.E. Services and Maintenance LimitedMachinery repair and installation
- Far-GB LimitedCleaning companies
- JM Groundworks LimitedLandscapers and gardeners
- L Pipe Services LtdSpecialist contractors
- Roll Cage Maintenance LimitedMachinery repair and installation
- W & M Plumbing and Heating LimitedPlumbers and heating engineers
What happens if Alter Construction Limited 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 December 2026.
| Companies House | Accounts delivered | Penalty |
|---|---|---|
| Up to 1 month late | 1 Jan 2027 to 31 Jan 2027 | £150 |
| 1 to 3 months late | 1 Feb 2027 to 31 Mar 2027 | £375 |
| 3 to 6 months late | 1 Apr 2027 to 30 Jun 2027 | £750 |
| More than 6 months late | From 1 Jul 2027 | £1,500 |
Penalties double if the accounts were also late the year before.
| HMRC (CT600) | From | Penalty |
|---|---|---|
| 1 day late | 1 Apr 2027 | £200 |
| 3 months late | 30 Jun 2027 | another £200 |
| 6 months late | 30 Sep 2027 | HMRC estimates the tax and adds 10% of the unpaid tax |
| 12 months late | 31 Mar 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
- 09259137
- Status
- Active
- Company type
- Private limited company
- Incorporated
- 10 October 2014 (12 years ago)
- Registered office
- 346A Farnham Road, Slough, Berkshire, SL2 1BT
- Nature of business
- Other specialised construction activities n.e.c. (SIC 43999)
- Year end
- 31 March (accounting reference date)
- Accounts type
- Micro-entity
- Last accounts made up to
- 31 March 2025
- Last confirmation statement
- 10 October 2025
Filing notes for specialist construction companies
Specialist contractors often work under CIS for main contractors. Retentions held back by the customer still count towards turnover once the work is done.
Similar companies in Slough
Other active specialist construction companies registered in Slough.
- An Eco Workers Ltd2023
- Ando Screeding Ltd2022
- Avib City Construction Ltd2020
- Ben Clifford Ltd2025
- Bestwood Construction Ltd2021
- Beyond the Basics Limited2003
- BK Site Solutions Ltd2026
- Bobo (Slough) Limited2015
All specialist construction companies in Slough · All trades in Slough · Specialist contractors across the UK
Frequently asked questions
When are Alter Construction Limited's accounts due?
Alter Construction Limited's next accounts are due at Companies House by 31 December 2026 (in 80 days), covering the period to 31 March 2026.
When is Alter Construction Limited's CT600 due?
The CT600 for the period to 31 March 2026 is due at HMRC by 31 March 2027, 12 months after the period end. The corporation tax itself is payable earlier, by 1 January 2027.
Is Alter Construction Limited still trading?
Alter Construction Limited 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 Alter Construction Limited do?
Alter Construction Limited is registered under Other specialised construction activities n.e.c. (SIC 43999).
How old is Alter Construction Limited?
Alter Construction Limited was incorporated on 10 October 2014, 12 years ago.
What is the penalty if Alter Construction Limited 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 Alter Construction Limited 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.