3I PLC
Company details
- Registered name
- 3I PLC
- Company number
- 00397156
- Registered office
- 1 KNIGHTSBRIDGE, LONDON, SW1X 7LX, UNITED KINGDOM · 117 other companies at this postcode
- Company type
- Public Limited Company
- Incorporated on
- 21 July 1945
- Status
- Active
- Age
- 81 years
- Nature of business (SIC)
- 64999 — Financial intermediation not elsewhere classified
- Accounts — next due
- 30 Sept 2027
- Accounts — last made up to
- 31 Mar 2026
- Confirmation statement — next due
- 15 Apr 2027
- Confirmation statement — last
- 01 Apr 2026
What the register says
Facts from the register, with the dates they are filed under. Not a score: what they mean is for you to judge, and every line can be checked against Companies House itself.
- 64 companies are registered at this address — commonly a formation agent or an accountant rather than an office.
- A person with significant control here also controls 62 other companies.
Companies House register snapshot, read 02/09/2026.
People with significant control
Beneficial owners holding over 25% of shares, voting rights or the right to appoint directors
Corporate structure
Who controls this company, and who they control in turn
Connections
Change history
Reconstructed from the dated records Companies House publishes
| Date | Change | Was | Now |
|---|---|---|---|
| 06/04/2016 | Person with significant control added | — | 3i Holdings Plc |
Documents for 3I PLC
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The full registration record as held today — name, number, status, registered office, company type, previous names, officers, PSC and SIC codes, timestamped for your file.
Every figure the company’s own accounts state, across each filed period, with year-on-year movement. Most UK companies file small or micro-entity accounts — a balance sheet and a headcount, no turnover or profit.
Who controls the company: persons with significant control, the nature of that control, the ownership graph and every other company those controllers hold.
Data protection register
Registered with the Information Commissioner's Office as a data protection fee payer.
The ICO publishes no company number, so this is matched on the registered name and confirmed by the postcode. Check the ICO entry before relying on it.
Get this company via API
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GET /v1/company/gb/00397156
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About 3I PLC (00397156)
3I PLC is a public limited company incorporated on 21 July 1945 and registered in the United Kingdom under company number 00397156. Its registered office is at 1 KNIGHTSBRIDGE, LONDON, SW1X 7LX, UNITED KINGDOM. The recorded nature of business is financial intermediation not elsewhere classified (SIC 64999). The company is currently active , with statutory accounts last made up to 31 March 2026. , and the person with significant control is 3i Holdings Plc. This profile is provided by opendata.bot by Noetikos, aggregating official data from Companies House bulk data , last refreshed 2 September 2026.
Companies at the same registered office
Financial intermediation not elsewhere classified across UK registers
The same sector and the same company, seen through every register we hold
Explore by sector
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