- Company number
- 17226508
- Incorporated
- 18 May 2026
- Registered office
- 1 Beauchamp Court, 10 Victors Way, Barnet, Hertfordshire, EN5 5TZ
- Nature of business
- Construction of domestic buildings; Plumbing, heat and air-conditioning installation; Other building completion and finishing
Five Nine Mechanical Limited is a newly incorporated private limited company registered in Barnet, company number 17226508, one of 201 building contractors in Barnet. Its next accounts are due at Companies House on 18 February 2028, and its first CT600 is due at HMRC on 17 May 2028.
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.
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Where Five Nine Mechanical Limited is registered
The registered office is in Barnet (EN5), in the Barnet local authority area, London. Show EN5 5TZ on a map.
Other trade companies in EN5
- Paysa Gas LtdPlumbers and heating engineers
- Greatway Business LtdInstallers
- Je Mobile Tyres LtdMechanics and garages
- Barnet Air LtdPlumbers and heating engineers
- Hutch Electrical LtdElectricians
- Nexflow Mechanical LtdSpecialist contractors
- A J Plant LtdMotor traders
- Plumbing365 LtdPlumbers and heating engineers
Shared registered office
72 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 Five Nine Mechanical 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 18 February 2028.
| Companies House | Accounts delivered | Penalty |
|---|---|---|
| Up to 1 month late | 19 Feb 2028 to 18 Mar 2028 | £150 |
| 1 to 3 months late | 19 Mar 2028 to 18 May 2028 | £375 |
| 3 to 6 months late | 19 May 2028 to 18 Aug 2028 | £750 |
| More than 6 months late | From 19 Aug 2028 | £1,500 |
Penalties double if the accounts were also late the year before.
| HMRC (CT600) | From | Penalty |
|---|---|---|
| 1 day late | 1 Jun 2028 | £200 |
| 3 months late | 31 Aug 2028 | another £200 |
| 6 months late | 30 Nov 2028 | HMRC estimates the tax and adds 10% of the unpaid tax |
| 12 months late | 31 May 2029 | 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
- 17226508
- Status
- Active
- Company type
- Private limited company
- Incorporated
- 18 May 2026
- Registered office
- 1 Beauchamp Court, 10 Victors Way, Barnet, Hertfordshire, EN5 5TZ
- Nature of business
- Construction of domestic buildings (SIC 41202)
Plumbing, heat and air-conditioning installation (SIC 43220)
Other building completion and finishing (SIC 43390) - Year end
- 31 May (accounting reference date)
- Accounts type
- No accounts filed yet
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 Barnet
Other active building contractors registered in Barnet.
- Flywall Dryliners Ltd2021
- FRB Builders Ltd2020
- GBK Engineering Limited2008
- Gentian Builder Ltd2020
- Giorgi Contractor Ltd2015
- Gjorllaku Construction Services Limited2025
- Gogo Build Ltd2018
- Goldfinch Services Ltd2026
All building contractors in Barnet · All trades in Barnet · Builders across the UK
Frequently asked questions
When are Five Nine Mechanical Limited's accounts due?
Five Nine Mechanical Limited's next accounts are due at Companies House by 18 February 2028 (in 494 days), covering the period to 31 May 2027.
When is Five Nine Mechanical 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 17 May 2027, due by 17 May 2028, and one for the period to 31 May 2027, due by 31 May 2028. Corporation tax is payable 9 months and 1 day after the end of each.
Is Five Nine Mechanical Limited still trading?
Five Nine Mechanical 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 Five Nine Mechanical Limited do?
Five Nine Mechanical Limited is registered under Construction of domestic buildings (SIC 41202); Plumbing, heat and air-conditioning installation (SIC 43220); Other building completion and finishing (SIC 43390).
How old is Five Nine Mechanical Limited?
Five Nine Mechanical Limited was incorporated on 18 May 2026, less than a year ago.
What is the penalty if Five Nine Mechanical 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 Five Nine Mechanical 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.