- Companies
- Civil engineering
- Harrow
- John Duffy Ltd
John Duffy Ltd
- Company number
- 14775400
- Incorporated
- 3 Apr 20233 years trading
- Registered office
- 10 College Road, First Floor, Harrow, HA1 1BE
- Nature of business
- Construction of bridges and tunnels; Construction of utility projects for fluids; Construction of other civil engineering projects n.e.c.; Other specialised construction activities n.e.c.
John Duffy Ltd is a 3-year-old private limited company registered in Harrow, company number 14775400, one of 121 civil engineering contractors in Harrow. Its next accounts are due at Companies House on 31 May 2027, and the CT600 for the period to 31 August 2026 is due at HMRC on 31 August 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 £912 (-31%) on the year before, to £2,029.
- Current assets of £4,153 against £2,880 owed within a year: 1.4 times cover.
- No employees reported for the latest year (directors are often not counted as employees).
- Balance sheets on record for 2 years, 2024 to 2025.
Net assets by year
| Year end | Net assets | Cash | Current assets | Owed within a year | Employees |
|---|---|---|---|---|---|
| 31 Aug 2025 | £2,029 | £4,153 | £2,880 | 0 | |
| 30 Apr 2024 | £2,941 | £4,249 | £2,316 | 1 |
Where John Duffy Ltd is registered
The registered office is in Harrow (HA1), in the Harrow local authority area, London. Show HA1 1BE on a map.
Other trade companies in HA1
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- Mia Maria Services LtdCleaning companies
- Ac Operations LtdScaffolders
- Verde Masters LtdLandscapers and gardeners
- Omega Works Group LtdLandscapers and gardeners
- Call 'Em LimitedPlumbers and heating engineers
- Swan Roofing Services LimitedRoofers
- DRV Property Solutions LtdPainters and decorators
Also registered at this address
14 other companies use the same registered office as John Duffy Ltd.
- Advanced Business Equipment Holdings LimitedProperty developers
- DC Roofing and Maintenance LimitedRoofers
- Normandy Roofing Services LimitedRoofers
- Oa Developments London LimitedProperty developers
- Ranex Building Contractors Ltd.Property developers
- Reading Construction Group LtdBuilders
- Ryeland Homes LtdProperty developers
- Skyspace Homes LimitedProperty developers
- Skyspace Properties LimitedProperty developers
- Southall Heights LimitedFinishing trades
- SWP Landscaping LimitedLandscapers and gardeners
- TDS Scaffolding LtdScaffolders
- Tonys Best Hand Car Wash LtdCleaning companies
- Wood Design Solutions LtdProperty developers
What happens if John Duffy 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 May 2027.
| Companies House | Accounts delivered | Penalty |
|---|---|---|
| Up to 1 month late | 1 Jun 2027 to 30 Jun 2027 | £150 |
| 1 to 3 months late | 1 Jul 2027 to 31 Aug 2027 | £375 |
| 3 to 6 months late | 1 Sep 2027 to 30 Nov 2027 | £750 |
| More than 6 months late | From 1 Dec 2027 | £1,500 |
Penalties double if the accounts were also late the year before.
| HMRC (CT600) | From | Penalty |
|---|---|---|
| 1 day late | 1 Sep 2027 | £200 |
| 3 months late | 30 Nov 2027 | another £200 |
| 6 months late | 29 Feb 2028 | HMRC estimates the tax and adds 10% of the unpaid tax |
| 12 months late | 31 Aug 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
- 14775400
- Status
- Active
- Company type
- Private limited company
- Incorporated
- 3 April 2023 (3 years ago)
- Registered office
- 10 College Road, First Floor, Harrow, HA1 1BE
- Nature of business
- Construction of bridges and tunnels (SIC 42130)
Construction of utility projects for fluids (SIC 42210)
Construction of other civil engineering projects n.e.c. (SIC 42990)
Other specialised construction activities n.e.c. (SIC 43999) - Year end
- 31 August (accounting reference date)
- Accounts type
- Micro-entity
- Last accounts made up to
- 31 August 2025
- Last confirmation statement
- 2 April 2026
Filing notes for civil engineering contractors
Civil engineering contractors usually carry plant and machinery, so capital allowances (the annual investment allowance and the main pool) do much of the work in the corporation tax computation.
Similar companies in Harrow
Other active civil engineering contractors registered in Harrow.
- K Engineering Ltd2023
- K. R. Interiors Limited2003
- Kirti Construction Limited2014
- Laar Prime Engineering Ltd2016
- Lexstone Building Limited2012
- Lixus Rail Ltd2018
- M K Comm Limited2016
- M X Construction Limited2014
All civil engineering contractors in Harrow · All trades in Harrow · Civil engineering across the UK
Frequently asked questions
When are John Duffy Ltd's accounts due?
John Duffy Ltd's next accounts are due at Companies House by 31 May 2027 (in 231 days), covering the period to 31 August 2026.
When is John Duffy Ltd's CT600 due?
The CT600 for the period to 31 August 2026 is due at HMRC by 31 August 2027, 12 months after the period end. The corporation tax itself is payable earlier, by 1 June 2027.
Is John Duffy Ltd still trading?
John Duffy 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 John Duffy Ltd do?
John Duffy Ltd is registered under Construction of bridges and tunnels (SIC 42130); Construction of utility projects for fluids (SIC 42210); Construction of other civil engineering projects n.e.c. (SIC 42990); Other specialised construction activities n.e.c. (SIC 43999).
How old is John Duffy Ltd?
John Duffy Ltd was incorporated on 3 April 2023, 3 years ago.
What is the penalty if John Duffy 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 John Duffy 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.