- Companies
- Electricians
- Sidcup
- Si Electrical Limited
Si Electrical Limited
- Company number
- 03479117
- Incorporated
- 11 Dec 199728 years trading
- Registered office
- 12 Hatherley Road, Sidcup, Kent, DA14 4DT
- Nature of business
- Electrical installation
Si Electrical Limited is a 28-year-old private limited company registered in Sidcup, company number 03479117, one of 178 electrical contractors in Sidcup. Its next accounts are due at Companies House on 31 October 2026, and the CT600 for the period to 31 January 2026 is due at HMRC on 31 January 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 £736 (+0%) on the year before, to £2.4M.
- Net assets rose in 8 of 9 year-on-year comparisons on record.
- Current assets of £3.1M against £950K owed within a year: 3.3 times cover.
- 24 employees on average, down from 27 the year before.
- Balance sheets on record for 10 years, 2015 to 2025.
Net assets by year
| Year end | Net assets | Cash | Current assets | Owed within a year | Employees |
|---|---|---|---|---|---|
| 31 Jan 2025 | £2.4M | £647K | £3.1M | £950K | 24 |
| 31 Dec 2023 | £2.4M | £521K | £2.8M | £547K | 27 |
| 31 Dec 2022 | £2.4M | £793K | £3M | £744K | 27 |
| 31 Dec 2021 | £2.4M | £1.4M | £3.3M | £1M | 27 |
| 31 Dec 2020 | £2.4M | £1.7M | £4.1M | £1.7M | 27 |
| 31 Dec 2019 | £2.5M | £2.3M | £6.7M | £4.2M | 27 |
| 31 Dec 2018 | £2.4M | £4.5M | £7.4M | £5M | 27 |
| 31 Dec 2017 | £2.1M | £3.9M | £6.8M | £4.7M | 2 |
| 31 Dec 2016 | £1.5M | £811K | £2.1M | £657K | 2 |
| 31 Dec 2015 | £1.1M | £476K | £1.9M | £819K |
Public contracts won
Si Electrical Limited has one public sector contract award on record; the ones with their own published value total £190K (2025). Source: Contracts Finder and Find a Tender award notices. These were matched by the company's exact name because the notice gave no company number.
| Buyer | Contract | Value | Awarded |
|---|---|---|---|
| National Maritime Museum | Cutty Sark - Lighting Upgrade | £190K | 3 Dec 2025 |
Where Si Electrical Limited is registered
The registered office is in Sidcup (DA14), in the Bexley local authority area, London. Show DA14 4DT on a map.
Other trade companies in DA14
- Evlor LtdElectricians
- Pfe Services LimitedElectricians
- CJM Property Services LimitedFinishing trades
- Top Local Trader LtdBuilders
- Bassett Electrical Group LimitedElectricians
- Flatline Flooring LtdFloor and wall tilers
- LDT Service's LimitedScaffolders
- Old Maidstone Road Hand Car Wash LtdMechanics and garages
Shared registered office
427 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 Si Electrical 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 31 October 2026.
| Companies House | Accounts delivered | Penalty |
|---|---|---|
| Up to 1 month late | 1 Nov 2026 to 30 Nov 2026 | £150 |
| 1 to 3 months late | 1 Dec 2026 to 31 Jan 2027 | £375 |
| 3 to 6 months late | 1 Feb 2027 to 30 Apr 2027 | £750 |
| More than 6 months late | From 1 May 2027 | £1,500 |
Penalties double if the accounts were also late the year before.
| HMRC (CT600) | From | Penalty |
|---|---|---|
| 1 day late | 1 Feb 2027 | £200 |
| 3 months late | 30 Apr 2027 | another £200 |
| 6 months late | 31 Jul 2027 | HMRC estimates the tax and adds 10% of the unpaid tax |
| 12 months late | 31 Jan 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
- 03479117
- Status
- Active
- Company type
- Private limited company
- Incorporated
- 11 December 1997 (28 years ago)
- Registered office
- 12 Hatherley Road, Sidcup, Kent, DA14 4DT
- Nature of business
- Electrical installation (SIC 43210)
- Year end
- 31 January (accounting reference date)
- Accounts type
- Total exemption (full)
- Last accounts made up to
- 31 January 2025
- Last confirmation statement
- 5 November 2025
- Charges (mortgages)
- 0 outstanding of 2 registered
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 Sidcup
Other active electrical contractors registered in Sidcup.
- Simon Webster Electrical Limited2024
- Sjsupplies Limited2015
- SLP Electrical Service London Ltd2021
- Sochin Electronic Systems Limited2016
- Sophia Electrical Limited2024
- Spectrum Electrical & Building Services Limited2021
- Springfield Site Services Limited2007
- Stanton Electrical Ltd2020
All electrical contractors in Sidcup · All trades in Sidcup · Electricians across the UK
Frequently asked questions
When are Si Electrical Limited's accounts due?
Si Electrical Limited's next accounts are due at Companies House by 31 October 2026 (in 19 days), covering the period to 31 January 2026.
When is Si Electrical Limited's CT600 due?
The CT600 for the period to 31 January 2026 is due at HMRC by 31 January 2027, 12 months after the period end. The corporation tax itself is payable earlier, by 1 November 2026.
Is Si Electrical Limited still trading?
Si Electrical 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 Si Electrical Limited do?
Si Electrical Limited is registered under Electrical installation (SIC 43210).
How old is Si Electrical Limited?
Si Electrical Limited was incorporated on 11 December 1997, 28 years ago.
Has Si Electrical Limited won public sector contracts?
Yes. Si Electrical Limited has one contract award from public bodies on Contracts Finder and Find a Tender (those with their own published value total £190K), most recently from National Maritime Museum.
What is the penalty if Si Electrical 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 Si Electrical 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.