“How much does custom software cost?” is the first question almost every buyer asks, and the one most agencies dodge. Here is a straight answer from how we price our own work. Every project differs, so treat these as ranges, not a quote.
Setup and build
- Proof of value, minimum-spec build: from £15k. The smallest version that proves the idea works.
- Full design spec with a dedicated team: up to about £140k.
- Multi-system platform: £450k and up, where the product has user roles, dashboards, tracking metrics and data licensing across several connected systems.
Every build starts with a discovery phase and a workshop to prioritise features and make design decisions. That is where the budget gets tied to what matters, and where most overspend is avoided.
Ongoing support and maintenance
Software is not finished at launch. Support starts at £1,500 + VAT a month and runs up to £9,000 + VAT a month, depending on support scope and how much continuous improvement you want. Alongside that sit the running costs people forget: user feedback and iteration, AI model tokens and third-party services. If your product uses AI features, token usage scales with how much people use it, so ask for an estimate.
What moves the price
Scope is the biggest factor, followed by integrations (every system your software must talk to adds work), compliance (healthcare and finance need audit trails, security testing and documentation) and how many user types and platforms you support. Design quality and the amount of data to migrate also add up quickly.
Be wary of quotes that are dramatically lower than the rest. They usually leave out discovery, testing, security or support, which return later as change requests.
Does AI make it cheaper?
It makes the build faster, which helps you get more into a first release. It does not remove design, architecture, review or testing. Treat any quote that promises a fraction of normal cost “because of AI” with caution and ask what has been cut.
So what
Insist on a discovery phase before committing to a full build, and make sure support and running costs are quoted separately. If you want to sense-check a number you have been given, we are happy to look. Our custom software development page sets out how projects run, and you can start a project for an honest view.