- Companies
- Installers
- London
- Key Builders Ltd
Key Builders Ltd
- Company number
- 09918603
- Incorporated
- 16 Dec 201510 years trading
- Registered office
- 4TH Floor Silverstream House, 45 Fitzroy Street, London, W1T 6EB
- Nature of business
- Other construction installation
Key Builders Ltd is a 10-year-old private limited company registered in London, company number 09918603, one of 2,278 installation companies (insulation, lifts, shutters and similar) in London. Its next accounts are due at Companies House on 28 September 2027, and the CT600 for the period to 28 December 2026 is due at HMRC on 28 December 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 up £60K (+100.3%) on the year before, to £173.
- Net assets rose in 5 of 9 year-on-year comparisons on record.
- Current assets of £99K against £75K owed within a year: 1.3 times cover.
- 2 employees on average, up from 1 the year before.
- Balance sheets on record for 10 years, 2018 to 2025.
Net assets by year
| Year end | Net assets | Cash | Current assets | Owed within a year | Employees |
|---|---|---|---|---|---|
| 31 Dec 2025 | £173 | £86K | £99K | £75K | 2 |
| 31 Dec 2024 | -£60K | £6,825 | £22K | £54K | 1 |
| 31 Dec 2023 | -£87K | £5,089 | £29K | £92K | 1 |
| 31 Dec 2022 | -£46K | £81 | £28K | £66K | 3 |
| 31 Dec 2021 | -£35K | £25K | £25K | £57K | 3 |
| 31 Dec 2020 | £2,170 | £63K | £18K | -2 | |
| 31 Dec 2019 | £955 | £45K | £45K | 0 | |
| 29 Dec 2019 | £100 | ||||
| 31 Dec 2018 | £219 | £2,704 | £8,494 | £10K | |
| 29 Dec 2018 | £100 |
Where Key Builders Ltd is registered
The registered office is in London (W1T), in the Camden local authority area, London. Show W1T 6EB on a map.
Other trade companies in W1T
- Preschools Cleaning Company LtdCleaning companies
- Northheat Plumbing & Heating LtdPlumbers and heating engineers
- Leuk Lift Engineering UK LtdMachinery repair and installation
- Az Maintenance Services LimitedFinishing trades
- Braintree Property Service LtdBuilders
- Nona Construction & Retrofit LtdBuilders
- Denvav LimitedBuilders
- Marshall Roofing Services LtdRoofers
Shared registered office
53 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 Key Builders 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 28 September 2027.
| Companies House | Accounts delivered | Penalty |
|---|---|---|
| Up to 1 month late | 29 Sep 2027 to 28 Oct 2027 | £150 |
| 1 to 3 months late | 29 Oct 2027 to 28 Dec 2027 | £375 |
| 3 to 6 months late | 29 Dec 2027 to 28 Mar 2028 | £750 |
| More than 6 months late | From 29 Mar 2028 | £1,500 |
Penalties double if the accounts were also late the year before.
| HMRC (CT600) | From | Penalty |
|---|---|---|
| 1 day late | 29 Dec 2027 | £200 |
| 3 months late | 28 Mar 2028 | another £200 |
| 6 months late | 28 Jun 2028 | HMRC estimates the tax and adds 10% of the unpaid tax |
| 12 months late | 28 Dec 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
- 09918603
- Status
- Active
- Company type
- Private limited company
- Incorporated
- 16 December 2015 (10 years ago)
- Registered office
- 4TH Floor Silverstream House, 45 Fitzroy Street, London, W1T 6EB
- Nature of business
- Other construction installation (SIC 43290)
- Year end
- 28 December (accounting reference date)
- Accounts type
- Total exemption (full)
- Last accounts made up to
- 31 December 2025
- Last confirmation statement
- 14 December 2025
- Previous names
- Keys Builders Ltd (until 4 Jan 2016)
Filing notes for installation companies (insulation, lifts, shutters and similar)
Installation companies (insulation, lifts, shutters, solar and similar) often buy stock and equipment up front, so stock at the year end and capital allowances both affect the tax bill.
Similar companies in London
Other active installation companies (insulation, lifts, shutters and similar) registered in London.
- Key Consulting Ltd2024
- KG Decor Ltd2011
- KGW Rigging Ltd2026
- Khouses Construction Ltd2022
- Kiba Ltd2026
- Kidslux Ltd2025
- Kilnbridge Fire Protection Ltd2025
- Kingfield Services Ltd2025
All installation companies (insulation, lifts, shutters and similar) in London · All trades in London · Installers across the UK
Frequently asked questions
When are Key Builders Ltd's accounts due?
Key Builders Ltd's next accounts are due at Companies House by 28 September 2027 (in 351 days), covering the period to 28 December 2026.
When is Key Builders Ltd's CT600 due?
The CT600 for the period to 28 December 2026 is due at HMRC by 28 December 2027, 12 months after the period end. The corporation tax itself is payable earlier, by 29 September 2027.
Is Key Builders Ltd still trading?
Key Builders 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 Key Builders Ltd do?
Key Builders Ltd is registered under Other construction installation (SIC 43290).
How old is Key Builders Ltd?
Key Builders Ltd was incorporated on 16 December 2015, 10 years ago.
What is the penalty if Key Builders 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 Key Builders 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.