- Company number
- NI726244
- Incorporated
- 11 Feb 20251 year trading
- Registered office
- 17 Clarendon Road, Clarendon Dock, Belfast, BT1 3BG
- Nature of business
- Construction of domestic buildings
Thornleigh D Ltd is a 1-year-old private limited company registered in Belfast, company number NI726244, one of 213 building contractors in Belfast. Its next accounts are due at Companies House on 11 November 2026, and its first CT600 is due at HMRC on 10 February 2027.
Key dates
This company has not filed accounts yet. First accounts are due 21 months after incorporation, and the first period can run longer than a year.
Is this your company?
File the first accounts to Companies House and the CT600 to HMRC yourself with A.X.E.L Filing. One set of questions, both filings, £49 flat. No accountant, no subscription.
File for Thornleigh D LtdOr get a reminder before each deadline
Free. We email you 60, 30, 14, 7 and 1 days before the accounts, CT600 and confirmation statement are due. Unsubscribe in one click.
Where Thornleigh D Ltd is registered
The registered office is in Belfast (BT1), in the Belfast local authority area, Northern Ireland. Show BT1 3BG on a map.
Other trade companies in BT1
- Atlas Property and Holdings LtdProperty developers
- Geohac LimitedGroundworks and demolition
- XM Vehicle Solutions LimitedMotor traders
- Shine Renewables NI LimitedElectricians
- The Rathstone Group LtdCleaning companies
- Chenyukeji LtdMotor traders
- Linnexttech Shop LtdMotor traders
- Techright Environmental Ireland LtdCleaning companies
Also registered at this address
19 other companies use the same registered office as Thornleigh D Ltd.
- Ballystrew Properties LtdProperty developers
- Bastide Ventures LtdProperty developers
- Camana Consulting LimitedSpecialist contractors
- D. & D. Flooring LimitedFloor and wall tilers
- Dof Developments LtdProperty developers
- Grass Machinery NI LimitedMachinery repair and installation
- Haley Vehicle Movements LtdMotor traders
- Indevair LtdPlumbers and heating engineers
- K Contracts LimitedMachinery repair and installation
- Larne Coachworks LimitedMechanics and garages
- Lofty Property Investments LtdProperty developers
- M H Motors LimitedMotor traders
- Razorback Properties LtdProperty developers
- Ringsend LimitedProperty developers
- Six-West LtdFinishing trades
- Sona Homes LtdProperty developers
- Sunswift Enterprises LimitedProperty developers
- TMR Electrical LimitedElectricians
- Tonnagh Beg Group LtdCivil engineering
What happens if Thornleigh D 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 11 November 2026.
| Companies House | Accounts delivered | Penalty |
|---|---|---|
| Up to 1 month late | 12 Nov 2026 to 11 Dec 2026 | £150 |
| 1 to 3 months late | 12 Dec 2026 to 11 Feb 2027 | £375 |
| 3 to 6 months late | 12 Feb 2027 to 11 May 2027 | £750 |
| More than 6 months late | From 12 May 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
- NI726244
- Status
- Active
- Company type
- Private limited company
- Incorporated
- 11 February 2025 (1 year ago)
- Registered office
- 17 Clarendon Road, Clarendon Dock, Belfast, BT1 3BG
- Nature of business
- Construction of domestic buildings (SIC 41202)
- Year end
- 31 March (accounting reference date)
- Accounts type
- No accounts filed yet
- Last confirmation statement
- 10 February 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 Belfast
Other active building contractors registered in Belfast.
- Thralcot Homes Limited2014
- Tierra N.I. Ltd2018
- Total UPVC Solutions Limited2019
- Unit Construction Ltd2014
- Valleyside Construction Limited2010
- Valleyside Developments Ltd2021
- Vanon Properties Limited2005
- Visual Construction Ltd2025
All building contractors in Belfast · All trades in Belfast · Builders across the UK
Frequently asked questions
When are Thornleigh D Ltd's accounts due?
Thornleigh D Ltd's next accounts are due at Companies House by 11 November 2026 (in 29 days), covering the period to 31 March 2026.
When is Thornleigh D Ltd's CT600 due?
The first accounts cover more than 12 months, so there are two Company Tax Returns: one for the 12 months to 10 February 2026, due by 10 February 2027, and one for the period to 31 March 2026, due by 31 March 2027. Corporation tax is payable 9 months and 1 day after the end of each.
Is Thornleigh D Ltd still trading?
Thornleigh D 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 Thornleigh D Ltd do?
Thornleigh D Ltd is registered under Construction of domestic buildings (SIC 41202).
How old is Thornleigh D Ltd?
Thornleigh D Ltd was incorporated on 11 February 2025, 1 year ago.
What is the penalty if Thornleigh D 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 Thornleigh D 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.