Hire an individual developer when the work is small, clearly defined, and you have someone in your business who can judge whether it is being done well. Hire a firm when the software matters to how the business runs, has to be maintained for years, or nobody internal can tell good work from bad.
That is the short answer, and it is roughly what you will read everywhere. It is also less useful than it sounds, because both labels describe how a supplier is packaged rather than how your software will actually get built. What decides that is who writes the code, whether you get to speak to them, and what happens when they are not there.
Key takeaways
- Without anyone on your side who can judge the work, you are not buying software so much as a claim that software has been written.
- The point where one developer stops being enough is usually about consequence, not complexity. One person is a single point of failure with no cover.
- The word "agency" tells you nothing about who writes your code. It covers two senior developers and a two hundred person shop equally.
- Paying agency rates and getting one junior developer working alone is the worst of both, and it is more common than it should be.
- If software is going to be central to your business for years, the honest answer may be an employee rather than any supplier.
When hiring one developer is the right answer
Plenty of work does not need a team, and paying for one is waste. A single good developer is the right call when the job is contained and you can describe it, when it will take weeks rather than quarters, and when the business will survive comfortably if it stops for a fortnight.
The condition people skip is the third one: someone on your side has to be able to judge the work. A developer working alone with no technical oversight is being asked to mark their own homework. If you have a technical founder, an internal lead, or anyone who can read the code and push back, a freelancer is often the most cost-effective route there is. If you do not, you are not buying software. You are buying a claim that software has been written.
When one person is not enough
The moment to stop is usually not about complexity. It is about consequence.
If the software runs something your business depends on, one person is a single point of failure with no backup. They get ill, they take a better offer, they lose interest halfway through. Your project does not pause politely, it stops. The same applies over the longer term: software you rely on needs maintaining for years, and an individual is under no obligation to still be available, or even still be a developer, in three years' time.
There is a quieter version of the same risk. One person building alone develops habits nobody checks. Decisions get made that only they understand, in a codebase only they can navigate. That is fine while they are there and expensive the day they are not. It is the same trap people fall into with an AI-built app they cannot maintain, arrived at by a different route.
What "agency" actually means
Most comparisons treat "agency" as one thing with a fixed set of trade-offs: more expensive, more capable, more distant. In practice the word covers a range so wide it is close to useless.
At one end, a small senior-led firm where the people who quote the work are the people who write it. At the other, a large agency where you meet an account manager and a sales engineer, sign, and then the build goes to whichever developers are free, sometimes in another company entirely. Both call themselves agencies. Both quote in the same range. You will not tell them apart from the website.
You will be told agencies cost more and give you less contact with the people building your software. That is true of some and not others. It is not a property of the category, it is a property of how a particular firm is set up. It is entirely possible to pay a full agency rate and end up with one junior developer working alone, which is the arrangement with the fewest advantages of any on this page.
The questions that cut through the label
Ask these of anyone, individual or firm, and the answers will tell you more than the category ever could.
- Who will actually write this, and will I be speaking to them? Not the account manager, not the lead who joins the first call. The person typing.
- What happens if that person is unavailable for a month? A good answer is specific. A vague one means the honest answer is "your project stops".
- Who is accountable if this goes wrong, and what can I do about it? Contracts, insurance and continuity are the real difference between a supplier and an individual, and they only matter on the day something fails.
- Can you tell me I am wrong? Someone whose income depends entirely on your next instruction will struggle to push back. Being told your idea has a problem is worth more than being told yes quickly.
We are a small senior-led firm, so our answers to these are easy: you work directly with the people writing your software, because there is nobody else for it to be handed to. We would rather you asked the questions than took our word for it.
When neither is the right answer
Sometimes the honest answer is that you need an employee, not a supplier.
If software is going to be central to what your business does, and you expect to be changing it continuously for years, at some point you want that capability inside the building. Suppliers are good at getting you there and good at work with a shape and an end. They are a poor substitute for owning the thing outright when the software is the business. If that is where you are heading, the useful question is not which supplier, it is what to build in-house and when to start.
And if you cannot yet describe what you want clearly enough for anyone to quote it, neither option will go well. That is not a hiring problem, it is a scoping one, and no amount of team depth fixes it. Our guide to what bespoke software costs in the UK covers what has to be pinned down before a number means anything.
What to do next
Work out which situation you are actually in before you start looking. Small and contained with technical judgement in-house points to an individual. Business-critical, long-lived, or beyond your ability to assess points to a firm. Then ignore the label and ask the four questions above, of everyone, including us.
If you are not sure which side of that line your project sits on, tell us what you are trying to build and roughly what it needs to do. We will give you an honest view, including telling you if you would be better off with one good developer than with us.
FAQs
What are the key differences between a freelancer and an agency?
Cost is the difference people expect, and it is the least reliable one. Day rates overlap far more than the labels suggest, and the cheaper rate is not the cheaper project if the work has to be redone later or nobody can maintain it. What genuinely differs is cover when your developer is unavailable, and whether there is a company carrying contractual obligations when something goes wrong. Our guide to what bespoke software costs in the UK covers the money side properly.
How do you hire the right developer?
Look at software they have built that is still running and still being changed, rather than a portfolio of launches. Ask what they would do differently if they started it again today. Then buy a small, paid piece of work before committing to the whole thing, because how someone handles a contained job tells you more than any interview will. If they will not take a small piece first, that is worth knowing early.