Company number

SC388838

WASHINGTON CONSULTING INTERNATIONAL, PLC

Active

Filing history Order extract (PDF) Monitor

✓ Active company on the official register. Next accounts due 31 March 2027.

Company details

Scotland, Scotland Contains OS data © Crown copyright and database right. Contains Royal Mail data © Royal Mail copyright and database right. Source: Office for National Statistics licensed under the Open Government Licence v.3.0.

Registered name: WASHINGTON CONSULTING INTERNATIONAL, PLC
Company number: SC388838
Registered office: 8 ALBANY STREET, EDINBURGH, EH1 3QB, SCOTLAND · 184 other companies at this postcode
Company type: Public Limited Company
Incorporated on: 15 November 2010
Status: Active
Age: 15 years
Nature of business (SIC): 70100 — Activities of head offices
Accounts — next due: 31 Mar 2027
Accounts — last made up to: 30 Sept 2025
Confirmation statement — next due: 14 Oct 2026
Confirmation statement — last: 30 Sept 2025

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.

A person with significant control here also controls 2 other companies.
The last accounts filed were dormant accounts — the company reported no trading. 30/09/2025

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

Mark Curtis Williamson Service Group (Cayman Islands) Trust

owns 25–50% of shares (through a trust) · holds 25–50% of voting rights · can appoint and remove directors (through a trust) · has significant influence or control (through a trust)

Notified 30/09/2016

Mark Curtis Williamson Service Group (Switzerland) Trust

owns 25–50% of shares (through a trust) · holds 25–50% of voting rights (through a trust) · can appoint and remove directors (through a trust) · has significant influence or control (through a trust)

Notified 30/09/2016

Mr Mark Curtis Williamson

owns 50–75% of shares (through a trust) · holds 50–75% of voting rights (through a trust) · can appoint and remove directors (through a trust) · has significant influence or control (through a trust)

Notified 04/04/2022

Corporate structure

Who controls this company, and who they control in turn

3 controllers Drag to move · scroll to zoom · double-click to expand

Company Person Current control Ended

Connections

Mark Curtis Williamson Service Group (Switzerland) Trust name only

owns 25–50% of shares · holds 25–50% of votes · can appoint and remove directors · has significant influence or control Notified 30/09/2016 Controls 2 companies

Mr Mark Curtis Williamson

born 10/1961 · United States owns 50–75% of shares · holds 50–75% of votes · can appoint and remove directors · has significant influence or control Notified 04/04/2022 Controls 3 companies

Mark Curtis Williamson Service Group (Cayman Islands) Trust name only

owns 25–50% of shares · holds 25–50% of votes · can appoint and remove directors · has significant influence or control Control ended 04/04/2022 Controls 2 companies

Change history

Reconstructed from the dated records Companies House publishes

Date	Change	Was	Now
04/04/2022	Person with significant control ceased	Mark Curtis Williamson Service Group (Cayman Islands) Trust	—
04/04/2022	Person with significant control added	—	Mr Mark Curtis Williamson
30/09/2016	Person with significant control added	—	Mark Curtis Williamson Service Group (Switzerland) Trust
30/09/2016	Person with significant control added	—	Mark Curtis Williamson Service Group (Cayman Islands) Trust

Documents for WASHINGTON CONSULTING INTERNATIONAL, PLC

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Company extract£1.99

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.

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Financial statements£3.99

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.

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Ownership report£3.99

Who controls the company: persons with significant control, the nature of that control, the ownership graph and every other company those controllers hold.

PDF Order

Data protection register

No entry found on the ICO register of fee payers under this name.

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Get this company via API

Every field on this page is available as structured JSON behind one endpoint and one API key.

GET /v1/company/gb/SC388838
X-Api-Key: $OPENDATA_KEY

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Frequently asked questions

What is the company number of WASHINGTON CONSULTING INTERNATIONAL, PLC?▾

According to the official registry, the company number of WASHINGTON CONSULTING INTERNATIONAL, PLC is SC388838.

Where is WASHINGTON CONSULTING INTERNATIONAL, PLC registered?▾

The registered office is 8 ALBANY STREET, EDINBURGH, EH1 3QB, SCOTLAND.

What is the SIC code of WASHINGTON CONSULTING INTERNATIONAL, PLC?▾

The nature of business is recorded under SIC code 70100 — Activities of head offices.

Who controls WASHINGTON CONSULTING INTERNATIONAL, PLC?▾

Mark Curtis Williamson Service Group (Cayman Islands) Trust is recorded as a person with significant control, and owns 25–50% of shares (through a trust), holds 25–50% of voting rights, can appoint and remove directors (through a trust), has significant influence or control (through a trust).

When are the next accounts of WASHINGTON CONSULTING INTERNATIONAL, PLC due?▾

The next annual accounts are due by 31 March 2027, and the last accounts were made up to 30 September 2025.

About WASHINGTON CONSULTING INTERNATIONAL, PLC (SC388838)

WASHINGTON CONSULTING INTERNATIONAL, PLC is a public limited company incorporated on 15 November 2010 and registered in the United Kingdom under company number SC388838. Its registered office is at 8 ALBANY STREET, EDINBURGH, EH1 3QB, SCOTLAND. The recorded nature of business is activities of head offices (SIC 70100). The company is currently active , with statutory accounts last made up to 30 September 2025. , and the person with significant control is Mark Curtis Williamson Service Group (Cayman Islands) Trust. This profile is provided by opendata.bot by Noetikos, aggregating official data from Companies House bulk data , last refreshed 2 September 2026.