Upgrade Umbraco to 17: Stability, Scale and Real-World Impact
Why upgrading Umbraco isn’t “just IT’s problem”
Umbraco 17 is the latest Long-Term Support (LTS) version of Umbraco, built on .NET 10 LTS. That combination gives you a modern, supported stack that will be around for years – not one more short‑lived stepping stone.
If you’re running Umbraco 13 (or older) and debating whether to upgrade Umbraco, you’re really deciding:
How much risk you’re comfortable carrying on security and support
How much technical debt you want to fund every time you change something
Whether your CMS is a growth platform or just another system to keep alive
With Umbraco 17, there’s finally a clear answer.
What’s new in Umbraco 17 – in business terms
Umbraco 17 runs on .NET 10 LTS, which means:
Security patches and performance updates for the long haul
A platform aligned with Microsoft’s current best practices
A heap of new features, performance improvements and peace of mind
Staying on older versions of Umbraco increasingly means:
Greater exposure to vulnerabilities and being hacked
Upgrading later becomes harder and more expensive
You don't get access to all the cool new features of Umbraco
A backoffice that finally scales with your organisation
If you are on an older version of Umbraco and considering upgrading, here are some key features of Umbraco 17, as well as the business and security benefits already mentioned:
Load balanced back office - if you have big teams, this is a huge benefit, with increased performance across your team
Removal of AngularJS: The backoffice is turbo charged now with modern web componants (LIT) and removed AngularJS. In short, its faster.
Stonger Headless Capabilities: RESTful and GraphQL API's are more robust. It's techy, but trust us, this is a big win!
Enghanced Security: Leveraging the latest security from .NET10 really does protect your website
New text editor: Another improvement to make content editing easier and faster
Multilingual: Specific blocks can now be translated rather than whole pages.
These improvements really add up. From large content teams such as membership organisations, housing providers and Universities, this transforms your teams performance.
Upgrading Umbraco from 13 to 17: common pitfalls
The platform now supports direct Umbraco 13 → 17 is officially supported. Upgrading is not always easy, and can be scary that your entire website breaks. The below information is quite technical, however to summarise, upgrading is highly recommended and if planned correctly, a smooth process.
From the v17 release notes and community upgrade reports, the main things to watch when you upgrade Umbraco are:
1. Platform and security changes
.NET 10 LTS adoption - Hosting, build agents, containers and pipelines all need to support .NET 10.
HTTPS required by default - Umbraco 17 enforces HTTPS out of the box (you can opt‑out, but shouldn’t in production). Any weak certificate or non‑TLS environments surface here fast.
Extension/API clean‑up - Old, unused extension methods are finally gone. Custom code and packages must target the supported APIs.
2. Content and editor behaviours
Real‑world upgrades have highlighted issues such as:
- Routing and culture quirks - Multilingual sites seeing 404s or odd route behaviour post‑upgrade if culture and hostname configurations weren’t robust to begin with.
Block editors and RTE blocks - Some projects report missing or inconsistent content in Block List, Block Grid or RTE blocks when jumping versions without carefully following migration guidance.
Older editors - Legacy patterns such as Nested Content need to be migrated to modern block editors. Leaving this “for later” is where a lot of upgrade pain lives.
None of these are reasons not to upgrade Umbraco – they’re reasons to have a structured plan.
How Spinbox upgrades Umbraco (without breaking your week)
At Spinbox, we see an Upgrade Umbraco project as an opportunity to improve the platform – not just tick a version box.
1. Discovery and risk assessment
We start by understanding:
Your current Umbraco version, hosting, packages and integrations
Content complexity, multi‑lingual setup, and editor workflows
Any legacy usage (Nested Content, obsolete property editors, custom backoffice code)
From there we score technical risk and agree the safest path to 17.
2. Upgrade roadmap and staging
Next, we:
Confirm the direct 13 → 17 route (or define interim steps if needed)
Update infrastructure to support .NET 10 and required dependencies
Clone your site into a staging environment and run the upgrade there first
We follow Umbraco’s version‑specific upgrade guides, then run:
Smoke tests (login, create/publish, media, search)
Regression tests for key user journeys
Data integrity checks for Block List / Block Grid / RTE content, including multilingual variants
3. Improving your content model and editor experience
Rather than just “making it work”, we use the move to 17 to tidy house:
Migrate legacy editors to modern blocks
Introduce Release Sets for campaign-style publishing
Configure the new Date Time Picker with appropriate time zones
Refine permissions and workflows to match how your team really works
You end up with an Umbraco build that’s not just current, but nicer to live with.
4. Production rollout and support
When everyone’s happy:
We schedule a controlled deployment window, with rollback options
Monitor logs, performance and search closely post‑go‑live
Support both IT and editors through the bedding‑in period
Ready to upgrade Umbraco – or plan your next build?
If you’re:
Running Umbraco 13 and need a safe path to 17
Planning a new website and want to start on Umbraco 17
Looking for a partner who understands both Umbraco and enterprise‑class integrations
…we’d love to talk to you.