A scale-up is a business growing fast and sustainably after proving its model. The ScaleUp Institute, using the OECD definition, describes it as a firm with average annualised growth in employees or turnover above 20% a year over three years, with 10 or more employees at the start of that period.
What it means
A start-up is still searching for a repeatable model. A scale-up has found one and is now expanding headcount, revenue, markets or all three. The 20% threshold is a statistical definition used for policy and research, but in practice founders use the word for any business that is outgrowing its original structure.
Growth at that pace puts pressure on systems, people and cash. Processes that worked for 15 staff often break at 50, and reporting that satisfied the founder rarely satisfies investors or lenders.
How it works in a UK business
UK scale-ups typically need stronger finance, operations and technology leadership before they can justify full-time hires in every seat. Many add fractional directors to build board reporting, forecasting and an operating rhythm, then hire permanently once the role is proven. Leadership Services supports scale-ups from its bench of senior directors, from £1,795 per month.
Frequently asked questions
Is a scale-up the same as a start-up?
No. A start-up is testing whether its product and business model work. A scale-up has already proved demand and is focused on expanding quickly and repeatably. The ScaleUp Institute definition requires 10 or more employees at the start of a three-year period of more than 20% annual growth, which most early start-ups would not meet.
What leadership does a scale-up usually need first?
Most scale-ups first feel the gap in finance, because investors and lenders want reliable forecasts and management accounts. Operations and technology leadership often follow as headcount grows. Fractional directors are a common way to fill these gaps without committing to several full-time executive salaries at once.
Last updated: 5 November 2026