- Companies
- Electricians
- Windsor
- Marks Sparks Limited
Marks Sparks Limited
- Company number
- 14370121
- Incorporated
- 22 Sep 20224 years trading
- Registered office
- ST Stephens House, Arthur Road, Windsor, Berkshire, SL4 1RU
- Nature of business
- Electrical installation
Marks Sparks Limited is a 4-year-old private limited company registered in Windsor, company number 14370121, one of 22 electrical contractors in Windsor. Companies House shows its accounts as overdue: they were due on 30 September 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 £6,939 (+103.6%) on the year before, to £238.
- Current assets of £27K against £27K owed within a year: 1.0 times cover.
- 1 employee on average during the year.
- Balance sheets on record for 2 years, 2023 to 2024.
Net assets by year
| Year end | Net assets | Cash | Current assets | Owed within a year | Employees |
|---|---|---|---|---|---|
| 30 Sep 2024 | £238 | £10K | £27K | £27K | 1 |
| 30 Sep 2023 | -£6,701 | £19K | £23K | £30K | 1 |
Where Marks Sparks Limited is registered
The registered office is in Windsor (SL4), in the Windsor and Maidenhead local authority area, South East. Show SL4 1RU on a map.
Other trade companies in SL4
- A3 Hand Car Wash and Valeting Center LimitedCleaning companies
- Time Watch Repair Watford LtdRepair services
- Mobile Tyre Services 24/7 LtdMechanics and garages
- Hullscrub Thames LtdCleaning companies
- Black Rose Automotive Group LtdMotor traders
- Maldec Hatchet Farm LimitedProperty developers
- Pinehill Homes Partnerships LtdProperty developers
- Heatsense Renewables LtdElectricians
Also registered at this address
16 other companies use the same registered office as Marks Sparks Limited.
- Cladbrook LtdProperty developers
- Dedicated Circuits LimitedElectricians
- GP Property MDX LtdProperty developers
- Heatsense Services LimitedPlumbers and heating engineers
- Lighting Logistics LimitedElectricians
- M T Manganelli LimitedSpecialist contractors
- Oduco LimitedFinishing trades
- Pro Landscapes MDX LtdLandscapers and gardeners
- Sam Residential LimitedProperty developers
- SB Fleet Assistance LimitedMechanics and garages
- Shades of Light LimitedElectricians
- The Marlow Land Company LimitedProperty developers
- Thomas Smith Heating and Gas LimitedPlumbers and heating engineers
- Trimidal LimitedRepair services
- Urban Designs & Developments (Wokingham) LimitedBuilders
- Walton and Green Electrical Services LtdElectricians
What happens if Marks Sparks Limited files late
If the accounts reach Companies House today, the late filing penalty is £150 (£300 if last year's accounts were also late). It rises at each step below.
| Companies House | Accounts delivered | Penalty |
|---|---|---|
| Up to 1 month late | 1 Oct 2026 to 31 Oct 2026 | £150 |
| 1 to 3 months late | 1 Nov 2026 to 31 Dec 2026 | £375 |
| 3 to 6 months late | 1 Jan 2027 to 31 Mar 2027 | £750 |
| More than 6 months late | From 1 Apr 2027 | £1,500 |
Penalties double if the accounts were also late the year before.
| HMRC (CT600) | From | Penalty |
|---|---|---|
| 1 day late | 1 Jan 2027 | £200 |
| 3 months late | 31 Mar 2027 | another £200 |
| 6 months late | 30 Jun 2027 | HMRC estimates the tax and adds 10% of the unpaid tax |
| 12 months late | 31 Dec 2027 | 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
- 14370121
- Status
- Active
- Company type
- Private limited company
- Incorporated
- 22 September 2022 (4 years ago)
- Registered office
- ST Stephens House, Arthur Road, Windsor, Berkshire, SL4 1RU
- Nature of business
- Electrical installation (SIC 43210)
- Year end
- 30 September (accounting reference date)
- Accounts type
- Total exemption (full)
- Last accounts made up to
- 30 September 2024
- Last confirmation statement
- 21 September 2026
Filing notes for electrical contractors
Electrical contracting companies are often a director plus a van and tools. Most fall within the micro-entity rules, so the accounts filed at Companies House are short, and the CT600 carries the tax detail.
Similar companies in Windsor
Other active electrical contractors registered in Windsor.
- Nova Electrical Group Ltd2020
- Sandford Electrical Services Limited1989
- Shades of Light Limited2009
- SL Fire & Electrical Services Limited2012
- Solar Warrior Ltd2010
- Spot on Electrics Ltd.2016
- ST Hanson Homes Limited2004
- Voltcrest Electrical Solutions Limited2025
All electrical contractors in Windsor · All trades in Windsor · Electricians across the UK
Frequently asked questions
When are Marks Sparks Limited's accounts due?
Marks Sparks Limited's accounts were due at Companies House on 30 September 2026 and the register shows them as overdue.
When is Marks Sparks 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 30 September 2025, due by 30 September 2026, and one for the period to 31 December 2025, due by 31 December 2026. Corporation tax is payable 9 months and 1 day after the end of each.
Is Marks Sparks Limited still trading?
Marks Sparks Limited is listed as active on the Companies House register (checked 12 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 Marks Sparks Limited do?
Marks Sparks Limited is registered under Electrical installation (SIC 43210).
How old is Marks Sparks Limited?
Marks Sparks Limited was incorporated on 22 September 2022, 4 years ago.
What is the penalty if Marks Sparks 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 Marks Sparks Limited on Companies House for filed documents, officers and the full history.
Based on the Companies House register (snapshot 1 Oct 2026, rechecked 12 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.