Umbraco 17 Upgrade: What it involves and how to get started

If your website runs on Umbraco, there’s a good chance the upgrade to version 17 is already on your radar — or it should be. Umbraco 17 is the latest Long-Term Support (LTS) release, built on .NET 10, and it represents the biggest step-change in the platform in several years. More immediately: the end-of-life deadlines for older versions are close, and the cost of missing them is real.

This article covers what the Umbraco 17 upgrade actually involves, which version you’re likely coming from, what’s new in the release, and how 16i approaches upgrade projects.

Why Umbraco 17 upgrade deadlines matter now

Umbraco follows a predictable release cycle, with Long-Term Support versions released every two years. Once a version reaches end of life, it stops receiving security patches, bug fixes, and official support. That means vulnerabilities go unaddressed, integrations with third-party packages become harder to maintain, and your site gradually accumulates technical risk.

The current deadlines are:

• Umbraco version

  End of life date

  Status

  Umbraco 7 / 8

  Already passed

  Unsupported — full migration required

  Umbraco 10 LTS

  June 2025

  No longer supported

  Umbraco 13 LTS

  December 2026

  Approaching — plan now

  Umbraco 16

  June 2026

  Already passed

  Umbraco 17 LTS

  November 2028

  Current LTS — upgrade target

If your site is running Umbraco 13, you have until December 2026 before support ends — but that timeline is shorter than it looks once you factor in discovery, development, testing, and deployment. Planning now avoids rushing later.

If your site is on Umbraco 16, support has already ended as of June 2026. Upgrading to 17 should be a priority.

What version are you running? Upgrade paths explained

The path to Umbraco 17 depends on which version you’re currently running.

Umbraco 13 → 17

This is the most common upgrade scenario and the most straightforward. Umbraco supports direct LTS-to-LTS upgrades, so a Umbraco 13 site can move directly to 17 without stepping through versions 14, 15, and 16. The .NET version moves from .NET 8 to .NET 10, and most well-maintained packages will have compatible releases available.

Umbraco 14, 15, or 16 → 17

If you’re running a non-LTS version (14, 15) or the recently end-of-life version 16, upgrading to 17 is typically a cleaner step than a cross-LTS jump. These versions are already on the modern .NET Core architecture, which reduces the complexity of the move.

Umbraco 7 or 8 → 17

This is not an upgrade in the conventional sense — it’s a migration. Versions 7 and 8 were built on the legacy .NET Framework (not .NET Core), and the architectural difference is too significant for a standard upgrade process. Moving from version 7 or 8 to 17 requires rebuilding the site on the modern platform. That’s a more significant project, but it’s also an opportunity to modernise the codebase, clean up years of accumulated technical debt, and build on a foundation that will serve you for the next five to eight years.

What’s new in Umbraco 17

Umbraco 17 is a substantial release. The headline changes that matter most to organisations running existing sites:

Built on .NET 10

Umbraco 17 runs on Microsoft’s .NET 10 framework, which brings meaningful performance improvements over .NET 8. Sites start up faster, handle concurrent requests more efficiently, and benefit from the broader ecosystem improvements Microsoft ships with each .NET release.

Rebuilt back office

The Umbraco back office has been fully re-engineered using a modern, web-component-based architecture. The editing experience is faster, more accessible, and designed to be extensible. For content teams who spend significant time in the CMS, the day-to-day experience is noticeably better — navigation is cleaner, workflows are more intuitive, and the interface scales properly on different screen sizes.

TipTap replaces TinyMCE as the rich text editor

Umbraco 17 ships with TipTap as its default rich text editor, replacing TinyMCE. This is a meaningful change for sites with complex content editing workflows. If you have customised TinyMCE configurations, these will need to be reviewed and migrated as part of the upgrade.

Release Sets for content scheduling

A significant new editorial feature: Release Sets allow editors to group multiple content items and publish them together at a scheduled time. For organisations managing large content releases — campaign launches, seasonal updates, product rollouts — this removes the coordination overhead of publishing items individually.

Improved performance and caching

Umbraco 17 introduces HybridCache, which significantly improves startup times on large sites with extensive content trees. Sites that previously had slow back-office load times due to content volume will see meaningful improvement.

Improved accessibility in the back office

Umbraco has worked with an external accessibility consultant to bring the back office into closer alignment with WCAG standards. This matters both for organisations with accessibility obligations for their internal tools and for teams with editors who use assistive technologies.

What the upgrade process involves

A well-planned Umbraco 17 upgrade follows a consistent sequence, regardless of the size of the site. The steps that matter most:

• Version audit: establishing exactly which version of Umbraco you’re running, which packages are installed, and which have Umbraco 17 compatible releases available

• Custom code review: identifying any code that interacts with Umbraco internals in ways that may be affected by breaking changes in version 17 — particularly TinyMCE configurations, custom back-office extensions, and middleware

• .NET version update: updating the project’s target framework from .NET 8 (Umbraco 13) to .NET 10 (Umbraco 17)

• Package updates: updating all Umbraco packages to versions compatible with 17 and .NET 10

• Database backup: a full backup of both the database and media library before any upgrade steps begin — non-negotiable

• Upgrade execution: applying the Umbraco 17 package, allowing the database migration to run, and resolving any issues that surface

• Testing: functional testing across content types, editors, integrations, and front-end templates

• Deployment: staged deployment through development, staging, and production environments

The complexity of each step varies depending on how heavily customised your site is, how many third-party packages you use, and how actively the site has been maintained. A relatively clean Umbraco 13 site with standard packages will upgrade more smoothly than a heavily customised site with bespoke back-office extensions.

How long does an Umbraco upgrade take?

Timelines depend on the site’s complexity, the version being upgraded from, and how much custom code needs reviewing. As a rough guide:

• Scenario

  Typical timeline

  Clean Umbraco 13 site, standard packages,
  minimal custom code

  2 to 4 weeks

  Umbraco 13 site with custom back-office
  extensions or complex integrations

  4 to 8 weeks

  Umbraco 7 or 8 migration
  (full rebuild on modern stack)

  8 to 16 weeks depending on site size

  Large enterprise platform with
  multiple environments

  Scoped individually after audit

These timelines include discovery, development, testing across environments, and deployment. They don’t include any additional work to take advantage of new Umbraco 17 features — like migrating to TipTap or implementing Release Sets — which can be scoped as a separate phase once the base upgrade is complete.

Ready to upgrade? Work with 16i

16i is an accredited Umbraco agency based in Cheltenham. We’ve been building and maintaining Umbraco sites across a wide range of sectors for many years — from corporate and manufacturing platforms to arts venues, trade portals, and hospitality brands.

Umbraco upgrade projects follow a consistent process: we start with an audit of your current site to establish exactly what’s involved, give you a realistic timeline and cost estimate, and then manage the upgrade through to deployment. We handle the technical complexity so your team doesn’t have to.

If your site is on Umbraco 13 and you haven’t started planning the upgrade to 17 yet, now is the right time to begin. The December 2026 end-of-life date is close enough that leaving it much longer will reduce your options and increase the risk of having to rush.

Get in touch at hello@16i.co.uk or call +44(0)1242 654 000.