The Portman Estate
The Portman Estate comprises 110 acres of Marylebone in London’s West End, including frontages to Oxford Street, Baker Street and Edgware Road, as well as two rural estates in Buckinghamshire and Herefordshire and a portfolio of assets outside London.
The Portman Estate is owned by a series of family trusts under the governance of Trustees and Directors and has invested considerably in refurbishment and upgrading properties to maintain the quality of stock. It exists for the long term and aims to be the destination of choice for residents, businesses, and visitors, where the buildings exceed market demand, the environment is distinctive, varied and vibrant and the level of service offered by the Estate is second to none. A core principle is to provide high quality buildings which are managed in a sustainable way, in order to establish an environmentally sound Estate for the future.
There are approximately 85 employees within The Portman Estate, across its Marylebone office at One Great Cumberland Place and its farm, Burtley in Buckinghamshire.
Modern Slavery and Human Trafficking Statement
The United Kingdom Modern Slavery Act 2015 (the “Act”) requires certain organisations to develop a slavery and human trafficking statement each year. It also sets out which organisations are required to comply.
The current structure of The Portman Estate means that we are not required to comply however we have voluntarily taken the decision to proactively comply with the legislation by setting out the steps we have already taken and those we plan to take, to ensure that there is no modern slavery or human trafficking either within our organisation or our supply chain. We seek to follow the BSI Standard – BS 25700 – to the extent that it is relevant to our business. The Standard provides guidance for addressing the risk of modern slavery, including prevention, identification, response, remediation, mitigation, and reporting. In 2025, we have also noted the updated ‘Transparency in Supply Chains’ statutory guidance on the content of modern slavery statements published pursuant to Section 54 of the Modern Slavery Act 2015.
We are committed to ensure that no one at The Portman Estate should be involved in modern slavery or human trafficking in any way. This applies equally to our trustees, directors, employees, tenants, suppliers and contractors as well as the wider public realm within which the Estate operates over which it has direct control. We already have in place procedures which are designed to embed our values and behaviours in the company, and these form an integral part of the recruitment and appraisal process for our team.
The Portman Estate became a certified B Corp organisation in 2022. B Corps are leaders in the global movement for an inclusive, equitable, and regenerative economy. Enhancing stakeholder value is paramount and preventing modern slavery is integral to this aim. B Corp certification lasts for three years and the Estate has applied for recertification and is expecting to hear in early 2026.
Our Purchasing Policy outlines our aspirations to meet the highest standards of environmental, social and ethical considerations. Many of our suppliers and contractors undergo a detailed appointment process to ensure not only that they have the technical competency to deliver services to us, but also that they share the Estate’s ethos and values.
A Supplier Charter was implemented in autumn 2023 which embeds our values across our supply chain. The Charter asks our suppliers to confirm to us that they hold their own policies and procedures in relation to the Act as well as other key legislative areas of compliance and, if not, we ask them to comply with ours. Currently 60 suppliers are signed up and we plan to roll this out further. Appropriate provisions are included in supplier contracts and enquiries made where necessary to ensure the transparency of supply chains. To complement the requirements we place on our suppliers, we have also produced a Sustainable Purchasing Guide for internal use by our own staff to enhance ethical decision-making on our part.
A risk-based approach is taken on training and awareness with relevant training provided periodically whilst new joiners also receive appropriate induction and training. A training session will be provided to all employees in 2026.
In the event that we discover that any of our employees, tenants, suppliers, contractors or anyone with a connection with The Portman Estate is involved in modern slavery and human trafficking in any way (directly or indirectly) the matter will be escalated to our Board of Directors so that appropriate action can be taken.
The Portman Estate has a Speak Up Policy: any concerns or allegations in connection with modern slavery or human trafficking can be addressed in confidence to the Speak Up Guardian, Tom Knight at The Portman Estate, 4th Floor, One Great Cumberland Place, London, W1H 7AL or via email – Tom.Knight@portmanestate.co.uk.
Approved by the Trustees and Directors of The Portman Estate on 3 December 2025.
