How much Security For Expenses should I be asked to deposit?
20 May 2026
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By Agreement
Security for Expenses, both its type and amount, is typically agreed by the two owners.
Party Wall Award
However, if they cannot reach an agreement, the surveyors involved will resolve the matter by issuing an award under section 10 of the Party Wall Act.
Where major works are planned, such as digging out a basement, it makes sense that the adjoining owner should not have to worry about the building owner’s ability (or inability) to cover any potential losses. This concern is particularly relevant if the building owner is a limited company with unknown, minimal or no assets, or is an offshore entity.
Examples
We have seen all sorts of different values, including:
- For a loft conversion in Kent: £1,000
- For a basement excavation in Belgravia: £35,000
- For a basement excavation in Hampstead: £50,000
- For a basement excavation Belgravia: £45,000
- For a basement excavation in Holland Park: £870,000
You can find out more about this in our article, "How Security for Expenses is Determined | Party Wall etc. Act 1996 Guide".