Isolated Systems Limited
Registered name: ISOLATED SYSTEMS LIMITED
Isolated Systems Limited made £6.3m revenue and £559k profit in the year to 31 May 2025.
Isolated Systems Limited’s revenue grew 3% to £6.3m in the year to 31 May 2025, with £559k profit and 53 employees. The company is classified under “other engineering activities” and is based in Heanor; we hold 4 years of its filed accounts.
- Status
- Active
- Location
- Heanor, East Midlands
- Age
- 56 yrs · since 1970
- Type
- Private Limited Company
Key figures
Badges are automated estimates derived from the filed figures — not statements of fact about the company.
Financial history
| Year to | 31 May 2022 | 31 May 2023 | 31 May 2024 | 31 May 2025 |
|---|---|---|---|---|
| Disclosure | Profit only | Full P&L | Full P&L | Full P&L |
| Profit & loss | ||||
| Revenue (turnover) | — | £7.1m | £6.1m | £6.3m |
| Cost of sales | — | £3.6m | £3m | £3.2m |
| Gross profit | — | £3.5m | £3.1m | £3.1m |
| Operating profit | — | £828k | £640k | £637k |
| Profit before tax | — | £839k | £712k | £763k |
| Profit after tax | £972k | £524k | £717k | £559k |
| Profit (best available) | £972k | £524k | £717k | £559k |
| Employees (average) | 60 | 61 | 52 | 53 |
| Ratios | ||||
| Profit margin | — | 7.4% | 11.7% | 8.9% |
| Gross margin | — | 49.9% | 50.9% | 49.4% |
| Revenue per employee | — | £116k | £117k | £118k |
| Profit per employee | £16.2k | £8.6k | £13.8k | £10.6k |
| Growth (year on year) | ||||
| Revenue growth | — | — | ▼14% | ▲2.7% |
| Profit growth | — | ▼46.1% | ▲36.8% | ▼22% |
| Headcount growth | — | ▲1.7% | ▼14.8% | ▲1.9% |
| Balance sheet — indirect signals, not revenue | ||||
| Cash at bank | £2.4m | £2.2m | — | — |
| Net assets | £3.6m | £3.9m | — | — |
| Fixed assets | £681k | £718k | — | — |
| Current assets | £4.7m | £4.5m | — | — |
| Debtors | £1.1m | £1m | — | — |
| Deferred income | £942k | £639k | — | — |
| Source | FullAccounts · bulk data Feb 2024 | FullAccounts · bulk data Feb 2024 | Accounts · bulk data Mar 2025 | Accounts · bulk data Mar 2026 |
How the business works
- Profit margin
- 8.9%
- Profit ÷ revenue.
- Gross margin
- 49.4%
- Gross profit ÷ revenue. High for software and services.
- Revenue per employee
- £118k
- Revenue ÷ average employees.
- Profit per employee
- £10.6k
- Profit ÷ average employees.
- Cash conversion
- —
- Cash generated from operations ÷ operating profit. Needs a cash-flow statement.
- Fixed assets ÷ revenue
- —
- Capital intensity. Low = capital-light, cheaper to start.
- Deferred income ÷ revenue
- —
- Customers paying upfront (subscriptions, deposits). Approximate when combined with accruals.
- Debtors ÷ revenue
- —
- Money owed by customers. Low = customers pay quickly.
Balance-sheet signals
Year-on-year changes in filed balance-sheet items. They can hint at momentum (or investment) but are not revenue or profit and must not be read as such.
- Net assets
- —
- Now —
- Cash at bank
- —
- Now —
- Headcount
- ▲2%
- Now 53
- Deferred income
- —
- Now —
- Fixed assets
- —
- Now —
Group structure
Subsidiaries (1)
- MCL Unitex LimitedFigures not disclosed
From the Persons with Significant Control register (corporate controllers only).
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Sources
Latest figures from accounts for the year to 31 May 2025 (profit £559k), from the Companies House accounts bulk data published Mar 2026. Spotted an error? Request a correction.
Updated from Companies House on 15 Oct 2026
Contains public sector information from Companies House licensed under the Open Government Licence v3.0. Data from Companies House, © Crown copyright. View the licence.