Capital expenditure describes spending on acquiring, improving or extending the useful life of fixed assets (for example, land, buildings, plant, equipment or significant IT systems), as opposed to day‑to‑day operating or revenue expenditure. In legal practice, it is a core concept in corporate, finance, tax, commercial property and public sector documentation.The term is not defined in a single overarching statute; instead, its meaning is derived from accounting principles and specific legislation, particularly tax legislation (for example, rules on capital allowances and deductions). Courts in the UK and Ireland have developed case law distinguishing capital from revenue expenditure, focussing on the nature and enduring benefit of the asset or enhancement.Capital expenditure provisions frequently appear in: financial covenants and baskets in loan agreements; restrictions and consent requirements in shareholders’ agreements and joint venture agreements; landlord and tenant clauses on service charge and repairs; project finance budgets; and corporate governance and approval matrices.Usage and underlying principles are broadly consistent across England and Wales, Scotland, Northern Ireland and Ireland, though practitioners must apply the term by reference to the relevant jurisdiction’s company, tax and accounting rules and any defined term in the particular contract or statute.