- Companies
- Specialist contractors
- Derby
- Alrock Mechanical Ltd
Alrock Mechanical Ltd
- Company number
- 10959854
- Incorporated
- 13 Sep 20179 years trading
- Registered office
- Riverside House Folly Road, Darley Abbey, Derby, DE22 1ED
- Nature of business
- Other specialised construction activities n.e.c.
Alrock Mechanical Ltd is a 9-year-old private limited company registered in Derby, company number 10959854, one of 161 specialist construction companies in Derby. Its next accounts are due at Companies House on 31 December 2026, and the CT600 for the period to 31 March 2026 is due at HMRC on 31 March 2027.
Key dates
Worked out from the year end and filing history on the Companies House register.
Is this your company?
File the accounts to Companies House and the CT600 to HMRC yourself with A.X.E.L Filing. One set of questions, both filings, £49 flat. No accountant, no subscription.
File for Alrock Mechanical LtdOr get a reminder before each deadline
Free. We email you 60, 30, 14, 7 and 1 days before the accounts, CT600 and confirmation statement are due. Unsubscribe in one click.
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 £223K (+22%) on the year before, to £1.2M.
- Net assets rose in 7 of 7 year-on-year comparisons on record.
- Current assets of £1.5M against £275K owed within a year: 5.4 times cover.
- 2 employees on average, up from 1 the year before.
- Balance sheets on record for 8 years, 2018 to 2025.
Net assets by year
| Year end | Net assets | Cash | Current assets | Owed within a year | Employees |
|---|---|---|---|---|---|
| 31 Mar 2025 | £1.2M | £818K | £1.5M | £275K | 2 |
| 31 Mar 2024 | £1M | £596K | £1.1M | £107K | 1 |
| 31 Mar 2023 | £999K | £456K | £1.1M | £167K | 1 |
| 31 Mar 2022 | £813K | £560K | £885K | £130K | 1 |
| 31 Mar 2021 | £402K | £348K | £529K | £152K | 1 |
| 31 Mar 2020 | £203K | £119K | £243K | £61K | 1 |
| 31 Mar 2019 | £33K | £52K | £57K | £32K | 1 |
| 31 Mar 2018 | £12K | £6,961 | £4,239 |
Where Alrock Mechanical Ltd is registered
The registered office is in Derby (DE22), in the Derby local authority area, East Midlands. Show DE22 1ED on a map.
Other trade companies in DE22
- Pulse Repairs LtdRepair services
- Liberty Autos Export LimitedMotor traders
- The Motor Bloke LimitedMechanics and garages
- JK Rapid Recovey LtdMachinery repair and installation
- Premier Rail Projects LtdMachinery repair and installation
- DWT and Sons LtdBuilders
- Hadi Auto Restore LtdMechanics and garages
- S8 Elec LtdElectricians
What happens if Alrock Mechanical 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 December 2026.
| Companies House | Accounts delivered | Penalty |
|---|---|---|
| Up to 1 month late | 1 Jan 2027 to 31 Jan 2027 | £150 |
| 1 to 3 months late | 1 Feb 2027 to 31 Mar 2027 | £375 |
| 3 to 6 months late | 1 Apr 2027 to 30 Jun 2027 | £750 |
| More than 6 months late | From 1 Jul 2027 | £1,500 |
Penalties double if the accounts were also late the year before.
| HMRC (CT600) | From | Penalty |
|---|---|---|
| 1 day late | 1 Apr 2027 | £200 |
| 3 months late | 30 Jun 2027 | another £200 |
| 6 months late | 30 Sep 2027 | HMRC estimates the tax and adds 10% of the unpaid tax |
| 12 months late | 31 Mar 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
- 10959854
- Status
- Active
- Company type
- Private limited company
- Incorporated
- 13 September 2017 (9 years ago)
- Registered office
- Riverside House Folly Road, Darley Abbey, Derby, DE22 1ED
- Nature of business
- Other specialised construction activities n.e.c. (SIC 43999)
- Year end
- 31 March (accounting reference date)
- Accounts type
- Total exemption (full)
- Last accounts made up to
- 31 March 2025
- Last confirmation statement
- 12 September 2026
- Previous names
- Rocks Mechanical Ltd (until 26 Jul 2019)
Filing notes for specialist construction companies
Specialist contractors often work under CIS for main contractors. Retentions held back by the customer still count towards turnover once the work is done.
Similar companies in Derby
Other active specialist construction companies registered in Derby.
- Andrews Construction Solutions Ltd2023
- Angry Beaver Properties Limited2025
- Apex Driveways and Patios Ltd2026
- Approved Building Control Ltd2017
- Ashbourne Building Consultancy Ltd2018
- Astor Industrial Pipework Services (Derby) Limited1998
- Atlas FS Ltd2025
- Bailey Earthmoving & Logistics Limited2021
All specialist construction companies in Derby · All trades in Derby · Specialist contractors across the UK
Frequently asked questions
When are Alrock Mechanical Ltd's accounts due?
Alrock Mechanical Ltd's next accounts are due at Companies House by 31 December 2026 (in 79 days), covering the period to 31 March 2026.
When is Alrock Mechanical Ltd's CT600 due?
The CT600 for the period to 31 March 2026 is due at HMRC by 31 March 2027, 12 months after the period end. The corporation tax itself is payable earlier, by 1 January 2027.
Is Alrock Mechanical Ltd still trading?
Alrock Mechanical 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 Alrock Mechanical Ltd do?
Alrock Mechanical Ltd is registered under Other specialised construction activities n.e.c. (SIC 43999).
How old is Alrock Mechanical Ltd?
Alrock Mechanical Ltd was incorporated on 13 September 2017, 9 years ago.
What is the penalty if Alrock Mechanical 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 Alrock Mechanical 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.