How much does a web app cost in the UK?
From about £1,500 for a single-purpose internal tool to £35,000 and beyond for a multi-team platform. Most business web apps, the portals and dashboards people actually log into, land between £4,000 and £12,000.
Below: the four bands and what separates them, the six things that genuinely move the number, what it costs to run once it is live, and how to make two very different quotes comparable.
By Lucas Reddington, full-stack developer and AI engineer, Northbytes. Last updated .
First, check you want a web app
A website is read. Pages that inform, persuade and get found, with nobody logging in. A web app is used: people sign in and do work, whether that is managing a booking, submitting a record or running a report. The two cost very different amounts, and the most expensive mistake on this page is paying web-app money for something a website would have done.
The test is simple. If nobody needs an account, you want a website. If people log in and change things, you want a web app. If the whole point is push notifications, working offline, or the camera and sensors in a phone, you want a mobile app, and that is a different budget again.
Plenty of businesses need a website in front and an application behind a login. Quoting them as one project is where confused numbers come from.
The four bands
Grouped by what the application has to do, because that is what the work follows. Not by industry, which barely matters.
Single-purpose internal tool
£1,500 - £4,000
One kind of user, one job: a booking log, a stock tracker, a form-and-records tool.
Everybody who logs in can do the same things, there is one data model, no payments and nothing to migrate. This is the band a spreadsheet usually graduates into, and it is where our entry price sits.
Customer portal or dashboard
£4,000 - £12,000
Your customers or staff sign in and see only their own records.
Two or more kinds of user with real differences in what they may see, which means permissions enforced on the server, an account system, and usually a migration of records you already hold somewhere else.
Multi-tenant SaaS product
£12,000 - £35,000
Something you sell: organisations sign up, subscribe and invite their own people.
Tenancy separation, subscriptions and billing, onboarding, an admin side and the analytics to know whether any of it works. Money changing hands is the single biggest step up in scope, because it drags in tax, refunds, failed payments and dunning.
Platform with deep integration
£35,000+
Several teams, several systems, and an audit trail somebody will be inspected on.
Real-time sync with systems you do not control, complex approval routing, regulated record-keeping. Delivered in phases so something useful is live early rather than everything arriving at once.
How we estimated these ranges
- The bands are our read of publicly advertised UK studio and agency pricing plus the quotes we write ourselves, grouped by scope rather than sector. They are a planning aid, not survey data, and they assume a UK-based team and no regulated-sector requirements.
- Northbytes prices - £1,500 to start a web app, £90 a month to host and maintain one with a database - are our published rates, not market averages. Every project is a fixed quote agreed before any code is written.
- Third-party fees such as payment processing come from the providers' own published pricing, listed under Sources and checked on the date shown there.
What actually moves the number
Six things, in roughly the order they matter. Notably absent: how many screens it has, which is what most people describe first.
How many kinds of user it serves
Not how many people, how many roles. One role is a form over a database. Three roles with different permissions is a permission model, and every screen then has to be right for each of them.
Whether money changes hands
Taking payments adds a payment provider, subscription states, failed-payment handling, refunds, invoices and VAT. It is the most reliably underestimated line in any web app quote.
How much data has to move
Migrating five years of records out of a spreadsheet or an old system is real work: mapped, cleaned as it moves, and reconciled against the original before anyone relies on it. Starting from empty is materially cheaper.
How many other systems it talks to
Each integration is its own small project, and the cost is dominated by the other end. A documented modern API is a day or two. A system with no API, or an export you have to schedule, is a fortnight.
Who the users are
Anything the public or a public-sector body uses has to meet accessibility obligations properly rather than nominally. We build to that standard either way, but it constrains design choices that a purely internal tool can make freely.
What happens when it is wrong
An internal tool that shows a stale number is an annoyance. A system whose output someone is audited on needs an audit trail, versioning and tested restores. That difference is scope, not polish.
A worked example, with the assumptions stated
A maintenance company with forty commercial clients wants to stop emailing job sheets. Clients should log in, see their own sites, raise a job, watch its progress and download the certificate at the end. Engineers should update jobs from a phone. The office should see everything.
That is three roles, so permissions are real. There is no payment inside the app, which keeps a whole category of work out. There are four years of jobs in a shared workbook, so there is a migration. It needs to send email when a job changes state, and nothing else integrates. Engineers are on phones, so it has to work properly on a small screen, but it does not need to work offline in a basement, which would push it towards a mobile app.
That lands in the portal band: roughly £6,000 to £9,000 for the first version, six to eight weeks, then £90 a month to run. If the same company later wanted clients to pay invoices inside it, that is not a small addition; it moves the project up a band.
The assumptions are the useful part of that example. When you get a quote, ask which of them the supplier has made.
What it costs after launch
The build is the number people compare. The running cost is the one that decides whether the thing is still alive in three years.
Hosting and maintenance
Ours is £90 a month for an app with a database, covering hosting in London, monitoring, backups, dependency and security updates and bug fixes. Elsewhere, application support is usually a retainer rather than a plan off a menu.
Third-party services
Payment processing fees, transactional email, SMS, mapping or whatever else the app calls. You pay these directly on your own accounts so you can see exactly what is being spent.
Changes and new features
Development work, quoted separately from maintenance. A useful planning figure is that a live app people rely on generates a steady trickle of small changes in its first year.
The domain and the certificates
A few pounds a year for the domain. TLS certificates should cost nothing and renew automatically; if a provider is charging you for them, ask why.
An application left unmaintained for two years does not stay still; its dependencies go out of support and the upgrade arrives later as a rebuild. The maintenance cost guide covers what a plan should actually include and where fees hide.
Seven questions to ask any quote
- How many user roles have you scoped, and what can each of them see?
- Are payments in or out? If in, whose problem are refunds and failed payments?
- How many records are you migrating, from what, and who checks the result?
- Which integrations are included, and what happens if the other system has no API?
- Who owns the source code, the designs, the data and the hosting accounts?
- What is the monthly cost afterwards, and is a bug fix included or quoted?
- When do I first see something clickable, and how often after that?
If you want the same treatment applied to your own idea, our web app development page sets out how a build runs, and planning an MVP covers how to get a first version in front of real users without building the whole thing.
Rough it out in thirty seconds
Answer four questions and see a range, plus which answers moved it. It is a planning aid built from our published prices, not a quote - the real number is fixed and agreed before anything starts.
Likely range for this shape of project
£1,500 – £2,400
Then £90 a month: hosting and maintenance for an app with a database.
What moved the number
Nothing yet - this is our published starting point. Our published starting point for a focused first version.
Assumes a UK-based team, no regulated-sector requirements, and that you own the result. The spread is real: the same brief lands differently once we have seen the actual data and the actual systems. Anything genuinely unusual we would rather scope properly than guess at.
Get the fixed numberCommon questions
How much does a web app cost in the UK?
A focused first version starts around £1,500 for a single-purpose internal tool. A customer portal or dashboard with two or more user roles typically lands between £4,000 and £12,000, a multi-tenant SaaS product with subscriptions between £12,000 and £35,000, and a multi-team platform with deep integrations above that. Our own entry point is £1,500 on a fixed quote agreed before any code is written, and you own the result.
Why is a web app cheaper than a mobile app?
One codebase, one deployment, no app store. A mobile app usually means building for iOS and Android, submitting to two review queues, supporting old OS versions people have not updated, and paying store commission on anything you sell inside it. A web app updates the moment you ask, is shareable by a link, and reaches everyone with a browser. If notifications, offline working or phone hardware are genuinely the point of your product, that changes the answer, and our mobile-versus-web comparison goes through it row by row.
What does a web app cost to run each year?
Budget the hosting and maintenance fee, plus whatever third-party services the app calls, plus a realistic allowance for changes. Ours is £90 a month for an app with a database, which covers hosting, monitoring, backups, updates and fixes. Payment processing, email delivery and similar services are billed to your own accounts. Most of the annual number for a small app is that monthly fee; most of the variance is how much you decide to change.
How long does it take to build?
Six to ten weeks from the first conversation to real users for a focused first version, including any data migration. Larger platforms take longer and should be delivered in phases so part of it is earning while the rest is built. You should be seeing something clickable from the second or third week either way; a project that shows you nothing until the end is a project you cannot steer.
How do I compare two very different quotes?
Make them describe the same thing. Ask each supplier how many user roles they have scoped, whether payments are in or out, how many records they are migrating and from where, which integrations are included, who owns the code and what the monthly cost is afterwards. A large part of the gap between two quotes for the same idea is usually that they are not quoting the same idea.
Sources
Figures quoted from outside Northbytes come from these sources, checked on 26 July 2026. Our own prices are our published rates.
Read next
Mobile app vs web app: which should you build?
Cost, updates, offline use, notifications and the 30% app store commission, compared side by side so you pick the right one first time.
How much does custom software cost in the UK?
Price bands by system type, two worked examples with the assumptions stated, the day-rate arithmetic behind every quote, and a checklist for reading one.
How much does a website cost in the UK?
What DIY builders, freelancers, studios and agencies really charge, what drives the price up, and what a small business should sensibly expect to pay.
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