How much does custom software cost in the UK?

The honest answer is that nobody can tell you from a web page, and this page is not going to pretend otherwise. What it will do is publish the bands the UK market actually quotes, show what the number is made of, and link one real priced job so you can judge the standard before you judge anybody’s quote.

Every market figure below was read from the publisher’s own page on 21 September 2026 and is linked in Sources.

At a glance

• Published UK bands run from about £10,000 to £600,000 and above. Small bespoke tools are commonly quoted at £20,000 to £60,000.
• Our own price is fixed and public: free fit call, £2,000 fourteen-day audit, then a scoped build price. The audit fee is not credited against a build.
• Running costs are commonly published at 15 to 25 per cent of build cost a year, plus hosting.
• Six things move the number, and the number of screens is not one of them.
• One build of ours is open to inspection, priced to the penny: 63 measured lines, £98,214.72.

Why is a number without a scope meaningless?

Two businesses ask for “a quoting system”. One wants a form that emails a finished PDF. The other wants something that reads a measured take-off, applies regional pricing, keeps a version history and syncs to their accounts package. Both describe it in one sentence and both use the same words.

The gap between those two is not a percentage. It is a different piece of software. Any supplier who quotes both from the sentence alone is either guessing high enough to be safe, which you overpay for, or guessing low to win the work, which you pay for later.

Custom software is priced the way an extension is priced. A builder who quotes before seeing the site is quoting for the version in their head, and the difference between that version and yours turns up later as a variation. The same thing happens in software, except the foundations are invisible, so the variations arrive further in and cost more to fix.

What is the difference between bespoke, custom and off-the-shelf?

Suppliers use three words and mean two things, which is worth clearing up before you compare any prices.

Custom and bespoke are the same thing: software written for you, which you own and can change. Bespoke is the more British word and sometimes signals a higher price bracket, but there is no technical distinction, and a supplier who tells you otherwise is describing their pricing rather than the software.

Off-the-shelf is a product you licence alongside other customers. You cannot change it, you cannot stop paying for it while you use it, and in exchange somebody else funds its development, security and support.

There is a third answer that is more common than either: keep the product for the core of the process and build only the part that does not fit. That is covered in the custom software or off-the-shelf guide, which includes a three-year sum at published list prices.

What do we actually charge?

The 30-minute fit call is free and nothing is purchased on it. The AI Constraint Audit is a fixed £2,000 over fourteen days, including three sixty-minute working sessions with the engineers who would scope any build. It produces four documents you own: a constraint map, an opportunity map, economic cases and a ranked next step.

A build is quoted as a fixed price after that, scoped to what the audit found. We do not publish a build band, because a band published without your process behind it would be a made-up number and you would be right to distrust it.

The audit fee is not credited against a build. That is deliberate. If it came off the build price, we would earn more by recommending a build than by recommending a £40 a month subscription, and you should discount any recommendation made under that incentive.

One real priced job you can open right now

We will not price your build from this page. What we will show you is what a piece of software we built actually produces, priced to the penny, so you can judge the standard before you judge the quote.

QSQuoter is a system we built and run. On 14 July 2026 it produced an issued job for Cheadle Construction of Cheadle, Stockport, reference JAY-AA-20260713: a first-floor build-over extension in Heaton Moor, priced across sixty-three measured lines at £98,214.72 including VAT. Preliminaries and site set-up £17,374. Bathrooms and en-suites £15,962. Internal walls and finishes £11,245. Mechanical and electrical £6,290. Six more sections, published in full, with a client copy and a tradesman copy, every line traceable to a dimension somebody can check.

The claim is deliberately narrow. It shows we can build software that produces a priced professional document to an auditable standard and keep it in daily use. It does not prove hours saved, a return on investment, or anything about a different industry, and we do not stretch it into those. What we cannot show you yet is stated plainly on our evidence page.

What are the UK price bands in 2026?

These are other people’s published bands, gathered so you can see the shape of the market rather than one agency’s view of it. They are market commentary, not quotes, and none of them is audited.

Band	Published UK range	What it typically covers	Source
Small bespoke tool	£20,000 to £60,000	Single function, few integrations, small user base	Make IT Simple
Focused custom system	£20,000 to £50,000	One workflow or pipeline, basic reporting, 5 to 15 users, two to four months	Unity Bridge
Mid-range platform	£60,000 to £200,000	Multi-module, third-party integrations, several user types	Make IT Simple
Multi-module system	£50,000 to £100,000	Several pipelines, document generation, permissions, four to eight months	Unity Bridge
Complex or enterprise	£200,000 to £600,000 and above	Multiple teams, extensive integration, compliance surface	Make IT Simple, Unity Bridge
Whole-market range	£10,000 to £500,000 and above	Quoted as the outer bounds by UK agencies	Red Eagle

Two things are true about that table at once. The bands agree with each other more than they disagree, which is a mild signal that they are describing something real. And not one of the agencies publishing them publishes its own price, so every figure is commentary about somebody else’s work.

Where the money goes inside a build is more useful than the headline. Square Root publishes a breakdown by phase: discovery and technical planning at 5 to 10 per cent, QA and compliance testing at 10 to 20 per cent, ongoing maintenance and support at 15 to 25 per cent annually, user interface design at £3,000 to £20,000, and cloud infrastructure at £200 to £2,000 a month. Use those percentages to sanity-check any quote you receive: a proposal with no line for testing or for the year after launch is incomplete rather than cheap.

The six things that actually move the price

1. How many decisions the software has to make

Storing and displaying information is cheap. Deciding something is not. Every rule (“if the job is over this size, route it to a senior estimator”) is a branch that has to be specified, built and tested. Ten rules is not ten times one rule, because the rules interact.

2. How many other systems it has to talk to

This is the one most people underestimate. A standalone tool is a known quantity. The same tool that has to read from your accounts package, write to your calendar and stay in step with a supplier feed is three integrations, and integrations fail in ways you do not control. Each one needs error handling for the day the other end changes something without telling you.

3. What state your existing data is in

If the information the system needs currently lives in one clean spreadsheet, that is a morning. If it lives across a shared inbox, three spreadsheets with different column names and one person’s memory, the software is the easy part. Data migration is routinely the single largest line on a build, and it is almost never in the customer’s original estimate.

4. How many different kinds of user

One person using a tool needs one screen and no permissions. An office team, a field team on phones and a director wanting a weekly view is three interfaces, a permission model and a decision about what each of them is allowed to see and change. That is not three times the work, but it is not one times it either.

5. What it costs when the software is wrong

A tool that suggests a task order can be wrong occasionally without much consequence. A tool that issues priced quotes to customers cannot. The second one needs validation, an audit trail and a way for a human to catch it before it goes out. Correctness is a cost, and it is the right one to pay when money or safety depends on the output.

6. Who owns and maintains it afterwards

Software is not a purchase, it is an asset with running costs. Hosting, updates when the platforms underneath it change, and someone to call. A quote that covers only the build is not wrong, but it is incomplete, and you should ask what year two looks like before you compare it with anything.

Why do day rates tell you less than you think?

A day rate is a real number, which makes it feel like solid ground. It tells you what an hour of someone’s attention costs. It does not tell you how many hours the job takes, and that is the entire question.

Two suppliers with the same day rate can differ several times over on the same brief, because one has built the thing before. Experience shows up as fewer days, not as a lower rate. When you compare quotes, compare the total for a defined outcome, and make sure both are describing the same outcome.

Time and materials is defensible in exactly one situation: genuine research, where nobody can know the shape in advance. If your project is not research, ask why the supplier needs you to carry the estimating risk.

What does a supplier need before a real quote is possible?

You do not need a specification. You need to be able to answer these:

1. What is the process today, step by step, including the awkward parts people work around.
2. How often does it happen, and how long does it take now.
3. Where does the information come from, and where does it need to end up.
4. What has to be true for the result to be correct.
5. Who will use it, and on what.
6. What happens today when it goes wrong.

If a supplier does not ask most of these, the number they give you is not about your business.

What should you never pay for?

Four lines that should not be on an invoice, and it is worth saying so in advance rather than arguing about them later.

Discovery billed twice. If a fixed price was quoted, discovery is how the supplier arrived at it. Being charged separately to define the work that has already been priced means the price was not real.

A licence on code you commissioned. If you paid for a build, you should own it. Paying per seat to use software you funded is the worst of both routes.

Change requests for work inside the original scope. Scope creep is real and chargeable. Re-describing something already written down is not.

Rework caused by the supplier’s own assumption. If they assumed your data was clean without asking, the consequences of that assumption are theirs. The contract should say which of you carries that.

What will the quote not include?

Five things recur, and all five are foreseeable.

Data migration and cleaning, which is usually the largest single omission. Training and the fortnight where the team is slower, not faster. Integration maintenance for the day a third party changes their interface. Hosting and the run rate, published at £200 to £2,000 a month. And the internal time: your people answering questions, testing, and deciding, which is a real cost even though nobody invoices for it.

The cost of getting it badly wrong is worth keeping in view too, and the UK has a public record of it. The National Audit Office reported that the FiReControl project was terminated in December 2010, seven years after it began, with at least £469 million wasted, no IT system delivered and eight of the nine new regional control centres standing empty. That is a public-sector project at a scale no reader of this page will attempt, but the mechanism is the same one at every size: a specification agreed before anyone understood the work.

What does three years cost, build against seats?

The comparison worth doing is not build against nothing. It is build against the subscriptions it would replace, over three years, with real prices.

Jabu Designs publishes a worked version for a fifteen-person business: a SaaS stack at a realistic £1,400 to £1,800 a month, which is £84,000 to £108,000 over five years, against a £25,000 bespoke platform at £120 a month hosting, reaching about £32,000 over the same period, with an optional £400 a month support arrangement adding £19,200. Those are their assumptions and their figures, not ours, and we link them so you can check the seat counts they used.

Run it yourself with three columns: what you pay today, what the build costs to make, and what the build costs to run. The trap is column three. A build does not remove your accounting package or your email, and most builds replace one licence rather than a stack. If your three-year totals land within twenty per cent of each other, cost is not the deciding factor and you should decide on fit, control and rate of change instead.

One line worth checking with your accountant: the part of a build that resolves genuine technological uncertainty may qualify for UK R&D tax relief. Under HMRC’s SME scheme that is an extra 86 per cent deduction on qualifying costs, a total of 186 per cent, with a payable credit for loss-making companies worth up to 10 or 14.5 per cent of the surrenderable loss. Routine development on mainstream frameworks does not qualify, so treat this as a possible reduction rather than a planned one.

Which questions make two quotes comparable?

• What is not included in this figure.
• What happens to the price if the integration turns out to work differently than expected.
• Who owns the code and the data at the end.
• What does it cost to run for a year after launch.
• What is the smallest version of this that would be useful, and what would that cost on its own.

That last one matters most. A supplier who can describe a smaller first version has understood the problem well enough to find its core. One who insists the whole thing must be built at once may simply not know which parts are load bearing.

When should you not build custom?

Being straight about this is part of the job. Do not commission custom software when:

• An off-the-shelf tool already does it and your objection is the subscription cost. Building is almost always the more expensive way to avoid a fee.
• The process changes every few months. You would be paying to set concrete around something still moving.
• Nobody internally owns the process. Custom software makes a defined process faster; it does not create the definition.
• You cannot say what “working” would look like. If success is not measurable, neither is completion.

Why we will not price your project from this page

Because a number produced without your process behind it is a guess, and a guess presented as a quote is the thing this whole page argues against. It would also be the easiest possible way to win an enquiry and the fastest way to lose the argument in month three.

What we do instead is spend half an hour on the process itself: what it costs you now, what a better version looks like, and what the smallest useful first build would be. You leave that call knowing what the problem is and what can and cannot be solved with software, whether or not you go on to work with us. If it turns out you should buy something off the shelf, we will say so. What we build and on what terms is on custom process systems.

What this does not apply to

This page is written for UK businesses turning over roughly £1m to £50m: an operations director at a 40-person distributor, a contracts manager at a construction firm, a finance lead at a clinic group. It assumes a process that repeats and somebody who can describe it.

It does not apply to sole traders or very small teams, where a subscription tool is nearly always the right answer. It does not cover consumer apps or products you intend to sell, which are priced against a market rather than against a process. It does not cover public-sector procurement. It is not tax advice on R&D relief. And every competitor band quoted is that publisher’s own market commentary, unaudited, and not a quote for your work.

When we are the wrong choice

If a product fits and your objection is the invoice, negotiate rather than build. We will say so on the free call and you will not owe us anything.

If you want a fixed price from a one-page brief, we are the wrong supplier, and you should be careful of the ones who will give you one.

If you want the whole thing built at once, we will propose the smallest useful first version, and some buyers find that an underwhelming answer.

If nobody internally owns the process, no supplier can supply that, and a build commissioned into a vacuum becomes an expensive version of the old confusion.

Sources

Read on 21 September 2026.

• Make IT Simple, how much does bespoke software cost. £20,000 to £600,000 and above; small bespoke tool £20,000 to £60,000; mid-range platform £60,000 to £200,000; complex enterprise £200,000 to £600,000 and above.
• Unity Bridge Solutions, custom CRM development UK. Focused system £20,000 to £50,000 over two to four months; multi-module £50,000 to £100,000 over four to eight months; enterprise £100,000 to £250,000 and above.
• Red Eagle, bespoke software cost UK. The £10,000 to £500,000 and above outer range, stated in the page title.
• Square Root, cost to develop software in the UK. Discovery and technical planning 5 to 10 per cent; QA and compliance 10 to 20 per cent; maintenance and support 15 to 25 per cent annually; interface design £3,000 to £20,000; cloud infrastructure £200 to £2,000 a month.
• Jabu Designs, how much does bespoke software cost. The five-year comparison: a SaaS stack at £1,400 to £1,800 a month reaching £84,000 to £108,000, against a £25,000 build reaching about £32,000, with £400 a month support adding £19,200.
• National Audit Office, the failure of the FiReControl project. Contract terminated December 2010, seven years after it began, at least £469 million wasted, no IT system delivered, eight of nine regional control centres empty.
• HMRC, R&D tax relief for small and medium-sized enterprises. The extra 86 per cent deduction giving 186 per cent in total, and the payable credit worth up to 10 or 14.5 per cent of the surrenderable loss.
• QSQuoter. Reference JAY-AA-20260713, 14 July 2026, 63 measured lines, £98,214.72.

Related reading

• Custom software or off-the-shelf: how to decide
• Outgrown your CRM: rebuild, replace or extend?
• How much does AI implementation cost in the UK?