- Company number
- 15791401
- Incorporated
- 20 Jun 20242 years trading
- Registered office
- 20-22 Wenlock Road, London, N1 7GU
- Nature of business
- Construction of commercial buildings; Construction of domestic buildings
Calsan Developments Ltd is a 2-year-old private limited company registered in London, company number 15791401, one of 12,075 building contractors in London. Its next accounts are due at Companies House on 31 March 2027, and the CT600 for the period to 30 June 2026 is due at HMRC on 30 June 2027.
Key dates
Worked out from the year end and filing history on the Companies House register.
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Where Calsan Developments Ltd is registered
The registered office is in London (N1), in the Hackney local authority area, London. Show N1 7GU on a map.
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- Get IT Done Builders LtdJoiners and carpenters
- Evolution Products LimitedMotor traders
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- Kenneth Brady LtdElectricians
- UK Import Export LtdBuilders
- Magic Door Services LimitedMachinery repair and installation
Shared registered office
804 companies on our pages use this registered office address. An address shared this widely is usually an accountant's office or a company formation agent's service address, not where the business trades from.
What happens if Calsan Developments 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 March 2027.
| Companies House | Accounts delivered | Penalty |
|---|---|---|
| Up to 1 month late | 1 Apr 2027 to 30 Apr 2027 | £150 |
| 1 to 3 months late | 1 May 2027 to 30 Jun 2027 | £375 |
| 3 to 6 months late | 1 Jul 2027 to 30 Sep 2027 | £750 |
| More than 6 months late | From 1 Oct 2027 | £1,500 |
Penalties double if the accounts were also late the year before.
| HMRC (CT600) | From | Penalty |
|---|---|---|
| 1 day late | 1 Jul 2027 | £200 |
| 3 months late | 30 Sep 2027 | another £200 |
| 6 months late | 30 Dec 2027 | HMRC estimates the tax and adds 10% of the unpaid tax |
| 12 months late | 30 Jun 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
- 15791401
- Status
- Active
- Company type
- Private limited company
- Incorporated
- 20 June 2024 (2 years ago)
- Registered office
- 20-22 Wenlock Road, London, N1 7GU
- Nature of business
- Construction of commercial buildings (SIC 41201)
Construction of domestic buildings (SIC 41202) - Year end
- 30 June (accounting reference date)
- Accounts type
- Total exemption (full)
- Last accounts made up to
- 30 June 2025
- Last confirmation statement
- 2 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 in London
Other active building contractors registered in London.
- Caluxon Group Limited2021
- Cambria Project Management Limited2003
- Cambridge Group Ltd2025
- Camden Projects Ltd2025
- Camel Sree Construction Limited2026
- Cameleon Group Ltd2022
- Camillo Construction Ltd2024
- Campbells Construction Ltd2024
All building contractors in London · All trades in London · Builders across the UK
Frequently asked questions
When are Calsan Developments Ltd's accounts due?
Calsan Developments Ltd's next accounts are due at Companies House by 31 March 2027 (in 170 days), covering the period to 30 June 2026.
When is Calsan Developments Ltd's CT600 due?
The CT600 for the period to 30 June 2026 is due at HMRC by 30 June 2027, 12 months after the period end. The corporation tax itself is payable earlier, by 1 April 2027.
Is Calsan Developments Ltd still trading?
Calsan Developments 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 Calsan Developments Ltd do?
Calsan Developments Ltd is registered under Construction of commercial buildings (SIC 41201); Construction of domestic buildings (SIC 41202).
How old is Calsan Developments Ltd?
Calsan Developments Ltd was incorporated on 20 June 2024, 2 years ago.
What is the penalty if Calsan Developments 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 Calsan Developments 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.