- Company number
- 15433017
- Incorporated
- 22 Jan 20242 years trading
- Registered office
- 142 Kings Road, Harrow, HA2 9JH
- Nature of business
- Construction of commercial buildings; Construction of domestic buildings
Costy Building Ltd is a 2-year-old private limited company registered in Harrow, company number 15433017, one of 793 building contractors in Harrow. Its next accounts are due at Companies House on 31 October 2026, and the CT600 for the period to 31 January 2026 is due at HMRC on 31 January 2027.
Key dates
Worked out from the year end and filing history on the Companies House register.
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Financial snapshot, 2025
From the balance sheet at 31 January 2025, as filed at Companies House.
Where Costy Building Ltd is registered
The registered office is in Harrow (HA2), in the Harrow local authority area, London. Show HA2 9JH on a map.
Other trade companies in HA2
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- JNJ Engineering LimitedCivil engineering
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- Grandwellautos LtdMotor traders
- Multisteel Powdercoating LtdPainters and decorators
- Neon Systems LtdElectricians
- Firstclass Facilities LtdCleaning companies
- PMD Construct LtdBuilders
What happens if Costy Building 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 October 2026.
| Companies House | Accounts delivered | Penalty |
|---|---|---|
| Up to 1 month late | 1 Nov 2026 to 30 Nov 2026 | £150 |
| 1 to 3 months late | 1 Dec 2026 to 31 Jan 2027 | £375 |
| 3 to 6 months late | 1 Feb 2027 to 30 Apr 2027 | £750 |
| More than 6 months late | From 1 May 2027 | £1,500 |
Penalties double if the accounts were also late the year before.
| HMRC (CT600) | From | Penalty |
|---|---|---|
| 1 day late | 1 Feb 2027 | £200 |
| 3 months late | 30 Apr 2027 | another £200 |
| 6 months late | 31 Jul 2027 | HMRC estimates the tax and adds 10% of the unpaid tax |
| 12 months late | 31 Jan 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
- 15433017
- Status
- Active
- Company type
- Private limited company
- Incorporated
- 22 January 2024 (2 years ago)
- Registered office
- 142 Kings Road, Harrow, HA2 9JH
- Nature of business
- Construction of commercial buildings (SIC 41201)
Construction of domestic buildings (SIC 41202) - Year end
- 31 January (accounting reference date)
- Accounts type
- Total exemption (full)
- Last accounts made up to
- 31 January 2025
- Last confirmation statement
- 21 January 2026
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 Harrow
Other active building contractors registered in Harrow.
- CPFM Construction Ltd2019
- CPS Prime Contractors Limited2022
- Cptel Ltd2025
- Crestcon Ltd2025
- Crisden Services Ltd2020
- Crislo Construction Ltd2021
- CRMM Ltd2025
- Crystal Core Ltd2026
All building contractors in Harrow · All trades in Harrow · Builders across the UK
Frequently asked questions
When are Costy Building Ltd's accounts due?
Costy Building Ltd's next accounts are due at Companies House by 31 October 2026 (in 18 days), covering the period to 31 January 2026.
When is Costy Building Ltd's CT600 due?
The CT600 for the period to 31 January 2026 is due at HMRC by 31 January 2027, 12 months after the period end. The corporation tax itself is payable earlier, by 1 November 2026.
Is Costy Building Ltd still trading?
Costy Building 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 Costy Building Ltd do?
Costy Building Ltd is registered under Construction of commercial buildings (SIC 41201); Construction of domestic buildings (SIC 41202).
How old is Costy Building Ltd?
Costy Building Ltd was incorporated on 22 January 2024, 2 years ago.
What is the penalty if Costy Building 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 Costy Building 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.