The Twentieth Century Society

Campaigning for outstanding buildings

Looking forward, giving back: Leaving a legacy to C20

Stained glass window by John Piper in the Sanderson Hotel (1979)

Image: John East

For over forty years, C20 Society has successfully campaigned to save some of Britain’s most beloved modern architecture and design. From iconic red phoneboxes, to art deco lidos, brutalist bus stations to pop-art murals, even helping Bankside power station to become the cathedral of art, Tate Modern.

We believe such good design enriches lives and contributes towards thriving communities, yet our shared heritage has never been more under threat.  In a changing world, we must prioritise imaginative reuse and retrofit of our buildings over needless demolition.

C20 receives a small annual grant from Historic England, but the majority of our funding comes directly from membership subscriptions, donations and legacies. If you’re thinking of writing your will, you can make a lasting difference. Together, we can protect the best of twentieth and twenty-first century architecture for future generations.

How your gift will help

As an independent charity, leaving a legacy to the C20 – however large or small – can have a huge impact across the most important areas of our work.

Casework is at the heart of what we do. Our small team tackle thousands of at-risk cases of each year, helping to secure listed status for remarkable buildings, while providing free guidance during the planning process.

Meanwhile our Campaigns lead the debate on the built heritage of the future. Advancing environmentally conscious arguments and championing grassroots community solutions.

Leaving a Legacy

To find out more, please read the FAQ’s below or get in touch:
020 7250 3857 /

Thames Barrier Park (1999)

Image: John East

Inheritance Tax

Tax is charged on estates exceeding a certain level. However, as a charity, legacies to C20 are exempt from inheritance tax if you are a resident of the United Kingdom. This means that even if your estate is liable for tax, none will be paid on any gift you leave us in your will.

Types of Legacy

There are two main types of legacy that you can give:

Specific pecuniary legacies: These consist of a specific amount of money to the Society. The drawback is that, if not reviewed regularly, the value of the cash legacy may fall through the effects of inflation unless it is index-linked.

Residuary legacies: These consist of the balance or part of the balance of your estate, once all your other wishes have been carried out. Many people like to leave a residuary legacy to their favourite good causes because they are express a a fraction of their estate, rather than a cash sum, and therefore retain their value over time.

Wording for a legacy

If you wish to remember the Society in your will, adding in a simple codicil expressing to support our work. As a guideline, we suggest the following wording for inclusion in your will:

‘I bequeath to the Twentieth Century Society (‘The Society’) of 70 Cowcross Street London EC1 6EJ (Registered Charity Number 1110244) the sum of £_________(for a pecuniary legacy), or; the residue of my estate (for a residual bequest) to be used by the Society at its discretion, or : X% of the residue of my estate (for a residual bequest), and I declare that the receipt of the Honorary Treasurer or other authorised officials for the time being shall be a good discharge to my Executors’.

Free will writing

If you wish to remember the Society in your will and would like some assistance, we can arrange a service help to write or amend your will free of charge.
To find out more, please contact us on: 020 7250 3857 or email

Acknowledging your gift

Please let us know if you have remembered C20 in your will – we don’t need proof or details – we’d simply like to thank you. It also means you can tell us if you’d like your gift acknowledged, or would prefer to remain anonymous, and if there are specific areas of our work that you would like to benefit.