There is no single legal definition of a startup in the UK. A company does not become a startup because it has a particular Companies House code, raises venture capital or has fewer than a fixed number of employees.
For Join a Startup, the useful definition is practical: a startup is a young or growth-oriented company building something new, trying to find or expand a repeatable business model, and operating with more uncertainty than a mature organisation. Some are venture-backed. Some are bootstrapped and profitable. Some stay small; others become large scaleups.
Startup is not the same as small business
A small business can be an excellent place to work without being a startup. A local accountancy practice, established retailer or family-owned manufacturer may be small but have a stable, proven model.
A startup usually has more change built into the job. The product, customer, team structure or priorities may still be evolving. That can mean broader roles and faster learning, but it can also mean less predictability.
Does a startup have to raise investment?
No. Equity finance is one way a business can finance growth: the British Business Bank describes it as raising capital by selling a stake in the business to investors. Companies can also grow from revenue, debt, grants or founder funding.
That is why Join a Startup does not use “venture-backed” as a hard gate.
What about scaleups?
A scaleup is usually a company that has moved beyond the earliest stage and is growing quickly. For statistical work, UK government and ONS material commonly use a high-growth definition based on sustained growth in employment or turnover over a three-year period, starting from at least 10 employees.
That definition is useful for statistics, but everyday startup hiring is messier. A company can operate like a scaleup without neatly meeting a statistical test every year.
Join a Startup therefore covers UK startups and scaleups hiring for themselves, without an arbitrary headcount ceiling.
What a startup job can feel like
Startup roles often come with some combination of:
- a smaller team
- more direct access to decision-makers
- wider ownership
- changing priorities
- fewer established processes
- closer contact with customers
- more visible impact when something works - or does not
None of those is automatically good or bad. The useful question is whether that level of uncertainty and ownership suits you.
The better question to ask
Do not ask only, “Is this technically a startup?”
Ask:
Is this the kind of company where I want to spend the next few years of my career?
Research what it sells, who its customers are, how it is funded, how large the team is, what the job actually owns and what evidence there is that the business is progressing.