Umbraco agency: development, upgrades and migration
16i is a certified Umbraco agency. We build Umbraco websites, upgrade sites stranded on unsupported versions, and migrate platforms from WordPress, Drupal, Kentico and Sitecore onto Umbraco.
We have been working with Umbraco for over fifteen years and have delivered hundreds of projects on it, from national manufacturers and international law firms to arts venues and luxury travel brands. We are based in Cheltenham and work with clients across Gloucestershire, Oxfordshire, Wiltshire, the Cotswolds and throughout the UK.
We are also a B Corp certified business, independently assessed on how we treat our people, our clients and our impact
What we do with Umbraco
Umbraco development
New Umbraco builds designed around what your organisation actually needs rather than what a template allows. Custom document types, bespoke functionality, and integration with the systems you already run. We build in .NET, which means the site can grow into a platform rather than needing replacing when requirements change.
Umbraco upgrades
Umbraco 13 reaches end of life in December 2026 and Umbraco 16 support ended in June 2026. If your site is on either, or on version 7 or 8, upgrading matters: unsupported versions stop receiving security patches. We handle upgrades from any version, including the larger rebuilds required to move from the legacy .NET Framework versions onto modern Umbraco.
Umbraco migration
We migrate sites onto Umbraco from WordPress, Drupal, Kentico, Sitecore, Joomla and bespoke platforms. The technical work is rarely the hard part. Preserving search rankings through the move is, which is why we treat redirect mapping and metadata preservation as core to the project rather than a launch-day task.
Umbraco support and maintenance
Ongoing support for Umbraco sites, whether we built them or not. Security patching, version updates, performance monitoring and development work as your requirements change. Several of our client relationships are measured in years rather than projects.
Umbraco Commerce
Ecommerce built natively into Umbraco rather than bolted on, so product content and site content are managed in the same place by the same team.
Where we work
We have one office. It is at Rockfield Business Park in Cheltenham, Gloucestershire, and our team works from it.
We mention that because it is worth being clear about. We work with clients across Gloucestershire, Oxfordshire, Wiltshire, Worcestershire and the wider Cotswolds, and equally with organisations in London, Bristol, the South West and further afield. What we do not have is a presence in each of those places, and we would rather say so than suggest otherwise.
In practice it rarely matters. An Umbraco project involves a handful of moments where being in the same room genuinely helps, and a great deal of work that does not. So we work whichever way suits you:
Come to us
Discovery workshops work well in our Cheltenham office, and there is decent coffee and parking.
We come to you
For workshops, stakeholder sessions and key milestones, we travel. Oxford, Bristol and Swindon are all comfortably within reach for a day.
Start with a video call
Most relationships begin with half an hour on Microsoft Teams, which is usually enough to establish whether it is worth going further.
If you are looking for an Umbraco developer in Oxford, Bristol, Swindon or anywhere else in the region, we would be glad to talk. We will be straightforward about whether we are the right fit.
Why we build on Umbraco
Umbraco is open source, which means no licence fees and no dependence on a vendor's pricing decisions. It is built on Microsoft .NET, which suits organisations already invested in Microsoft infrastructure and brings a mature security model. And it imposes very little on how a site is structured, which means we build what a project needs rather than working around what a platform allows.
It is not the right answer for every project. A ten-page brochure site with no integrations does not need it. Where it earns its place is on sites with genuine complexity: multiple content types, real integration requirements, large content teams, or a platform that has to evolve over years.
Umbraco for large-scale projects
Much of our Umbraco work is at the more complex end. We build trade portals used daily by over a thousand installers, secure systems for international law firms, and ticketing-integrated platforms for arts venues running hundreds of performances a year.
That work has a different shape from a standard website build. It involves integration with back-office and third-party systems, security requirements that are reviewed by the client's own IT function, content structures that have to work for several teams at once, and platforms that are expected to run for a decade.
If your project sits in that territory, the question worth asking any agency is what they have built at that scale and what went wrong on it. We are happy to answer both.
Who we work with
Our clients range from Cheltenham organisations to national charities, arts institutions and international businesses, including Everyman Theatre, Grant UK, Dynamic Lives, The Sub Rooms and Elmore Court
16i invested a lot of time and effort into understanding what our sector was about. What was so impressive was their technical level, their professionalism, and their commitment to understanding what you need as a customer, plus their continual support throughout the journey.
Frequently asked questions
Do you work with clients outside Gloucestershire?
Yes. We are based in Cheltenham and work with clients across the UK, including London, the South West, the Midlands and further afield. Umbraco projects run well remotely, and we travel for discovery workshops and key milestones where it is useful.
Can you take over an Umbraco site built by another agency?
Regularly. We audit the existing build first so we can be clear about what we have inherited and what it will cost to maintain or improve. Sites vary considerably in how well they have been built, and it is better to establish that at the start than discover it later.
How much does an Umbraco website cost?
It depends on complexity rather than page count. A straightforward brochure site is a different undertaking from a platform with integrations, multiple content types and bespoke functionality. We scope after a discovery conversation rather than quoting upfront, because a figure given before understanding the requirement is a guess.
What version of Umbraco should we be on?
Umbraco 17 is the current long-term support release, built on .NET 10 and supported until November 2028. If you are on Umbraco 13, support ends in December 2026. If you are on 16, support has already ended. Versions 7 and 8 are long unsupported and require a rebuild rather than an upgrade.
Are you an official Umbraco partner?
Yes, we are a certified Umbraco agency and have been working with the platform for over fifteen years.
Talk to us about your Umbraco project
Whether you are planning a new Umbraco build, need to upgrade a site on an unsupported version, or want to migrate from another platform, we would welcome a conversation. An initial discussion is free and carries no obligation, and if Umbraco is not the right answer for your project we will say so.
Get in touch at hello@16i.co.uk or call +44 (0)1242 654 000.