- Companies
- Builders
- Downpatrick
- Cosyinsulation Limited
Cosyinsulation Limited
- Company number
- NI643491
- Incorporated
- 30 Jan 20179 years trading
- Registered office
- 38 Ballyhornan Road, Downpatrick, BT30 6RH
- Nature of business
- Construction of commercial buildings; Construction of domestic buildings
Cosyinsulation Limited is a 9-year-old private limited company registered in Downpatrick, company number NI643491, one of 28 building contractors in Downpatrick. Its next accounts are due at Companies House on 30 November 2026, and its first CT600 is due at HMRC on 31 August 2026.
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 up £113K (+117.1%) on the year before, to £210K.
- Net assets rose in 4 of 7 year-on-year comparisons on record.
- Current assets of £625K against £488K owed within a year: 1.3 times cover.
- 4 employees on average during the year.
- Balance sheets on record for 8 years, 2017 to 2024.
Net assets by year
| Year end | Net assets | Cash | Current assets | Owed within a year | Employees |
|---|---|---|---|---|---|
| 31 Aug 2024 | £210K | £256K | £625K | £488K | 4 |
| 31 Aug 2023 | £97K | £207K | £556K | £481K | 4 |
| 31 Aug 2022 | £130K | £325K | £513K | £393K | 4 |
| 31 Aug 2021 | £64K | £304K | £445K | £369K | 4 |
| 31 Aug 2020 | -£77K | £80K | £161K | £206K | 3 |
| 31 Aug 2019 | -£107K | £11K | £48K | £172K | |
| 31 Aug 2018 | -£85K | £20K | £32K | £129K | |
| 31 Aug 2017 | -£32K | £14K | £24K | £64K |
Where Cosyinsulation Limited is registered
The registered office is in Downpatrick (BT30), in the Newry, Mourne and Down local authority area, Northern Ireland. Show BT30 6RH on a map.
Other trade companies in BT30
- Ajc GRP LtdElectricians
- S J B Painting LtdPainters and decorators
- Corinas Cleaning LtdCleaning companies
- I P Recovery LimitedMechanics and garages
- Loughview Trading Co LimitedInstallers
- Titan Fabric and Surface LtdCleaning companies
- MCC&R LtdProperty developers
- Willow Cove Contracts LtdGroundworks and demolition
Also registered at this address
10 other companies use the same registered office as Cosyinsulation Limited.
- Ballyhornan Property 1 LimitedProperty developers
- Ballyhornan Property 2 LimitedProperty developers
- Cosy (Hampton) LimitedProperty developers
- Cosy Roof (UK) LtdRoofers
- Cosy Roof Developments LimitedProperty developers
- Cosysolar LimitedFinishing trades
- Kap Properties (Ardglass) LimitedProperty developers
- Kap Properties LtdProperty developers
- Lesley Holywood Properties LimitedProperty developers
- Ppco No.0 LimitedRoofers
What happens if Cosyinsulation 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 30 November 2026.
| Companies House | Accounts delivered | Penalty |
|---|---|---|
| Up to 1 month late | 1 Dec 2026 to 31 Dec 2026 | £150 |
| 1 to 3 months late | 1 Jan 2027 to 28 Feb 2027 | £375 |
| 3 to 6 months late | 1 Mar 2027 to 31 May 2027 | £750 |
| More than 6 months late | From 1 Jun 2027 | £1,500 |
Penalties double if the accounts were also late the year before.
| HMRC (CT600) | From | Penalty |
|---|---|---|
| 1 day late | 1 Mar 2027 | £200 |
| 3 months late | 28 May 2027 | another £200 |
| 6 months late | 28 Aug 2027 | HMRC estimates the tax and adds 10% of the unpaid tax |
| 12 months late | 28 Feb 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
- NI643491
- Status
- Active
- Company type
- Private limited company
- Incorporated
- 30 January 2017 (9 years ago)
- Registered office
- 38 Ballyhornan Road, Downpatrick, BT30 6RH
- Nature of business
- Construction of commercial buildings (SIC 41201)
Construction of domestic buildings (SIC 41202) - Year end
- 28 February (accounting reference date)
- Accounts type
- Total exemption (full)
- Last accounts made up to
- 31 August 2024
- Last confirmation statement
- 29 January 2026
- Charges (mortgages)
- 1 outstanding of 1 registered
- Previous names
- Cosy Roof Insulation Limited (until 27 Mar 2017)
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 Downpatrick
Other active building contractors registered in Downpatrick.
- DK Bricklaying Ltd2025
- DPH Construction Ltd1997
- Edgewater Limited1999
- G Macauley Plastering Ltd2025
- Grant Bros Developments Ltd2014
- Hanna & Smyth Contracts Ltd2015
- Horizon Design & Build Ltd2026
- Intire Fitout Ltd2024
All building contractors in Downpatrick · All trades in Downpatrick · Builders across the UK
Frequently asked questions
When are Cosyinsulation Limited's accounts due?
Cosyinsulation Limited's next accounts are due at Companies House by 30 November 2026 (in 48 days), covering the period to 28 February 2026.
When is Cosyinsulation Limited's CT600 due?
The first accounts cover more than 12 months, so there are two Company Tax Returns: one for the 12 months to 31 August 2025, due by 31 August 2026, and one for the period to 28 February 2026, due by 28 February 2027. Corporation tax is payable 9 months and 1 day after the end of each.
Is Cosyinsulation Limited still trading?
Cosyinsulation 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 Cosyinsulation Limited do?
Cosyinsulation Limited is registered under Construction of commercial buildings (SIC 41201); Construction of domestic buildings (SIC 41202).
How old is Cosyinsulation Limited?
Cosyinsulation Limited was incorporated on 30 January 2017, 9 years ago.
What is the penalty if Cosyinsulation 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 Cosyinsulation 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.