- Companies
- Installers
- Welwyn Garden City
- SJ Systems Ltd
SJ Systems Ltd
- Company number
- 09139781
- Incorporated
- 21 Jul 201412 years trading
- Registered office
- 80 Heronswood Road, Welwyn Garden City, AL7 3ET
- Nature of business
- Other construction installation; Maintenance and repair of motor vehicles
SJ Systems Ltd is a 12-year-old private limited company registered in Welwyn Garden City, company number 09139781, one of 19 installation companies (insulation, lifts, shutters and similar) in Welwyn Garden City. Its next accounts are due at Companies House on 31 March 2027, and the CT600 for the period to 30 June 2026 is due at HMRC on 30 June 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 £400 (-0.8%) on the year before, to £50K.
- Net assets rose in 3 of 9 year-on-year comparisons on record.
- Current assets of £72K against £5,874 owed within a year: more than 10 times cover.
- No employees reported for the latest year (directors are often not counted as employees).
- Balance sheets on record for 10 years, 2016 to 2025.
Net assets by year
| Year end | Net assets | Cash | Current assets | Owed within a year | Employees |
|---|---|---|---|---|---|
| 30 Jun 2025 | £50K | £72K | £5,874 | 0 | |
| 30 Jun 2024 | £50K | £84K | £15K | 2 | |
| 30 Jun 2023 | £50K | £65K | £15K | 2 | |
| 30 Jun 2022 | £50K | £54K | £3,885 | 1 | |
| 30 Jun 2021 | £63K | £76K | £14K | 1 | |
| 30 Jun 2020 | £59K | £66K | £7,888 | 1 | |
| 30 Jun 2019 | -£50K | -£67K | £8,212 | ||
| 30 Jun 2018 | -£50K | -£54K | £2,489 | ||
| 30 Jun 2017 | £48K | £3,554 | |||
| 30 Jun 2016 | £46K |
Where SJ Systems Ltd is registered
The registered office is in Welwyn Garden City (AL7), in the Welwyn Hatfield local authority area, East of England. Show AL7 3ET on a map.
Other trade companies in AL7
- Mechanicalwise LtdInstallers
- Azalea Services LimitedSpecialist contractors
- Malmech and Mannion LimitedMechanics and garages
- T&D Construction Group LtdFinishing trades
- Vertec Roofing and Building LtdRoofers
- Selectlane LtdMotor traders
- Af Pressure Washing LtdCleaning companies
- Jet Professional LtdCleaning companies
What happens if SJ Systems 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 March 2027.
| Companies House | Accounts delivered | Penalty |
|---|---|---|
| Up to 1 month late | 1 Apr 2027 to 30 Apr 2027 | £150 |
| 1 to 3 months late | 1 May 2027 to 30 Jun 2027 | £375 |
| 3 to 6 months late | 1 Jul 2027 to 30 Sep 2027 | £750 |
| More than 6 months late | From 1 Oct 2027 | £1,500 |
Penalties double if the accounts were also late the year before.
| HMRC (CT600) | From | Penalty |
|---|---|---|
| 1 day late | 1 Jul 2027 | £200 |
| 3 months late | 30 Sep 2027 | another £200 |
| 6 months late | 30 Dec 2027 | HMRC estimates the tax and adds 10% of the unpaid tax |
| 12 months late | 30 Jun 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
- 09139781
- Status
- Active
- Company type
- Private limited company
- Incorporated
- 21 July 2014 (12 years ago)
- Registered office
- 80 Heronswood Road, Welwyn Garden City, AL7 3ET
- Nature of business
- Other construction installation (SIC 43290)
Maintenance and repair of motor vehicles (SIC 45200) - Year end
- 30 June (accounting reference date)
- Accounts type
- Micro-entity
- Last accounts made up to
- 30 June 2025
- Last confirmation statement
- 11 May 2026
- Previous names
- SJ Classics Ltd (until 17 May 2021)
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 Welwyn Garden City
Other active installation companies (insulation, lifts, shutters and similar) registered in Welwyn Garden City.
- Smartier Group Ltd2019
- Summit Render Supplies London Limited2021
- Ultra KBB Ltd2020
- Unique Surfaces Plus Limited2017
- Adbrook Fire Protection Ltd2026
- Build on Time Limited2010
- Cdi Drylining Limited2022
- Coletta Doors Solutions Limited2011
All installation companies (insulation, lifts, shutters and similar) in Welwyn Garden City · All trades in Welwyn Garden City · Installers across the UK
Frequently asked questions
When are SJ Systems Ltd's accounts due?
SJ Systems Ltd's next accounts are due at Companies House by 31 March 2027 (in 169 days), covering the period to 30 June 2026.
When is SJ Systems Ltd's CT600 due?
The CT600 for the period to 30 June 2026 is due at HMRC by 30 June 2027, 12 months after the period end. The corporation tax itself is payable earlier, by 1 April 2027.
Is SJ Systems Ltd still trading?
SJ Systems 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 SJ Systems Ltd do?
SJ Systems Ltd is registered under Other construction installation (SIC 43290); Maintenance and repair of motor vehicles (SIC 45200).
How old is SJ Systems Ltd?
SJ Systems Ltd was incorporated on 21 July 2014, 12 years ago.
What is the penalty if SJ Systems 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 SJ Systems 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.