Software House vs Agency vs Consultancy: What's the Difference?

Software house vs agency vs consultancy comes down to one question: what does the company actually make money from? An agency sells projects, a software house sells software (its own product, or custom systems it builds and runs), and an IT consultancy sells hours. That business model decides how you pay, who owns the code and who runs the work day to day.

The labels shift between markets: "software house" is common in the UK and much of Europe, while US buyers tend to say "dev shop" or "custom software development company". I'm a freelance developer based in Denmark. That makes me none of the three, but I compete with all of them for some projects, so read with that in mind.

The short answer: three business models

My rule of thumb: if something needs to launch and then mostly be maintained, look at an agency. If the system is the business, or an existing product already covers most of what you need, look at a software house. If you already have people who can lead development and you're short on hands or specialist skills, a consultancy is built for exactly that.

The lines blur in practice, so treat the table as a starting point. If you're not yet sure what kind of developer your project needs in the first place, start with my overview of the different types of developers.

The agency: projects with a launch date

A web or digital agency is set up to take a project from idea to launch. It usually brings strategy, design, copywriting and development under one roof, and that combination is what you pay for.

The agency earns money when a project is sold, delivered and closed on budget, and afterwards from recurring work: hosting, updates, support and a monthly block of hours. Three consequences follow:

• The agency has a strong incentive to finish. That's good for deadlines, but the fastest route to launch isn't always best for the system five years out.
• Many agencies standardize on one stack, such as a particular CMS (content management system) or e-commerce platform, because it makes projects faster to deliver. That works well when your project resembles their others, and less well when it doesn't.
• Recurring revenue often comes from hosting and support plans, so ask what it costs to move to another supplier before you sign.

For a website or online store, an agency is often the right call, especially when design and content matter as much as code. For a pure development job it can get expensive, because you pay for disciplines you don't use. I've weighed that trade-off in freelancer vs agency: cost, risk and quality.

The software house: software built to last

"Software house" covers two quite different businesses. Find out which one you're talking to.

The product company: an existing product, adapted to you

Some software houses sell their own product, for example a booking, membership or ERP system for a specific industry. They earn money from licenses or subscriptions and from configuring and integrating the product for each client.

For you, that means getting something that already works for others in your industry, often much faster and cheaper than building from scratch. The trade-off is that you usually get a right to use it, not the code. The roadmap is set by the supplier and its whole customer base, not by you alone.

The custom development house: bespoke software plus long-term support

Other software houses make their living building systems for individual clients: customer portals, internal tools, integrations and apps. They tend to have fixed teams of developers, testers and project managers, established processes, and a support contract that runs for years after launch.

Their revenue comes from development and from the long relationship, so the business is built to stay with you. That's a real strength for business-critical systems, but the organization and the price can be oversized for a smaller project.

The IT consultancy: you rent hours and expertise

An IT consultancy sells people's time. That means developers, architects, testers or project managers working on-site or remotely as part of your team, for months or years. You'll also see this called staff augmentation or, in parts of Europe, body leasing. Some consultancies sell strategy, architecture or procurement advice too, but the core model is the same: hours.

The key metric in a consultancy is utilization, the share of consultant time that can be billed. That shapes what you get:

• You pay for effort, not for an outcome. If the work takes longer than expected, you're usually the one paying for the extra hours.
• You have to lead the work yourself. Consultants follow your priorities, work in your systems and often use your tools. Without someone to set direction, you've bought skilled hands without a head.
• People rotate. When a contract ends, consultants move on, and knowledge leaves with them unless it's written down.

The model fits larger organizations with an in-house engineering team that needs extra capacity or specialist skills for a while. If what you're missing is the strategic role rather than more hands, a part-time fractional CTO may be a better fit than a full-time consultant.

A lot of Nordic and Western European companies buy this kind of capacity from nearshore consultancies in Poland, the Baltics or Portugal, or from offshore teams further away. Rates can be lower, and I've covered what that means for communication, time zones and control in the pros and cons of offshore software development.

When each model is the wrong choice

Every model has a type of project it handles badly, and suppliers rarely volunteer which.

Skip the agency if

• You need a business-critical system with lots of rules and integrations that has to evolve for years.
• You need development and nothing else: no design, copy or marketing.
• Your project doesn't fit the agency's standard platform, and they recommend it anyway.

Skip the software house if

• You need a first version to test an idea. A large team with heavy process is expensive while you're still working out what to build.
• You pick an off-the-shelf product but have needs none of its other customers share. You'll end up paying to fight the product.
• The job is small, like a single integration or one new feature, and the firm's minimum engagement is bigger than your project.

Skip the consultancy if

• Nobody on your side can lead development and make technical decisions.
• You want a fixed price for a finished result.
• The work has a clear start and end and can be specified up front. A fixed-price project is usually more predictable than open-ended time and materials.

Where a freelance developer fits

A freelance developer is none of the three, but borrows a little from each. Like a custom development house, I build bespoke software and can stay on afterwards for maintenance and new features. Like a consultancy, I can work inside your team and your systems. The difference is that you talk directly to the person writing the code, and there's no organization whose utilization targets or license revenue you're paying for.

Before larger builds, I run a paid fixed-price discovery phase so we both know what's being built before any code is written. The code sits in your repository from day one, so you're not tied to me if you ever want to switch.

There are also projects where I'm the wrong choice. If you need five full-time developers starting next month, that's a software house or a consultancy. If you need a new brand identity, copy and a campaign alongside the website, an agency is better equipped. And if an off-the-shelf product already does what you need, buy it rather than paying me to build it again.

How to tell what a supplier really is

Labels tell you less than you'd expect. Some agencies call themselves software houses because it sounds more technical, and some software houses rent out consultants when projects are thin. Ask about the model instead.

The ownership question matters most with software houses that build "custom" software on top of their own proprietary platform or framework. You may own what was built for you, but not the foundation it sits on. I go deeper on that in who owns the code when a developer builds it for you.

The answers also reveal whether the supplier will think alongside you or just deliver what you ordered, a difference I cover in technical partner vs vendor.

Next steps: pick the model before the supplier

Many buyers start by collecting suppliers and end up comparing quotes that aren't comparable. Flip the order:

1. Describe the project on one page: what needs building, who will use it and what should happen after launch.
2. Decide whether you need an outcome or capacity. An outcome points to an agency, a software house or a freelancer. Capacity points to a consultancy.
3. Check whether an existing product covers most of the need before you pay for custom development.
4. Get two or three quotes on the same brief, ideally from different types of supplier, and ask the five questions above.

If you want to see which projects I take on and how working with me goes, have a look at my services as a freelance full-stack developer.

Frequently asked questions

Is a software house more expensive than an agency?+

It depends more on the project than on the type of firm. An existing product can be far cheaper than a custom build, because other customers have already paid for the development. A from-scratch build with a dedicated team and a long support contract often costs more than a typical agency project, because the system is larger and has to last longer. Compare total cost over three to five years.

Is staff augmentation the same as hiring a consultancy?+

Mostly, yes. Staff augmentation is the consultancy model in its purest form: you add external developers to your own team and manage them yourself, usually on hourly or day rates. Some consultancies also offer managed teams that take more responsibility for delivery. Ask which one you're getting, because it decides who is accountable when deadlines slip.

What can I do if I'm locked into a software house's platform?+

Start by mapping what you actually own and control: data, code, domain and accounts. Request a full export of your data and check the contract for notice periods and exit assistance. Moving in stages, such as building new parts outside the platform first, is often cheaper than switching everything at once. Get an independent developer to assess it before you decide.

Which type of supplier is best for an MVP?+

Usually a small team or a freelance developer rather than a large software house or a consultancy. An MVP (a first version built to test an idea) needs fast decisions, few people and room to change direction. An agency can work well if design and launch matter a lot. What matters most is a clearly defined first version with a fixed price.