I upgraded a test instance to Sitecore 10.5 the day it dropped, and the first thing I tried to do was install a package. It stopped me. The Package Installer and Package Designer are disabled by default now. You turn them on through config when you actually need them, then turn them back off. That single default is a decent summary of the whole release. 10.5 is careful, security-minded, and light on new toys, and it's that way on purpose.

If you were waiting for a blockbuster feature release, this isn't it. Sitecore isn't pretending otherwise. 10.5 is a quality-of-life and scene-setting release. The interesting part is what it sets up, and I'll get to that. First, let's be clear about what actually landed.

The arc from 10.4 to here

To read 10.5 correctly, you have to remember how we got here.

10.4 shipped at the end of April 2024. It was a real feature release, over 200 changes, SQL Server 2022 support, AKS support, analytics and Solr indexing improvements, and direct support for custom languages. That was the last time XP got a big marketing moment.

Then came a long, quiet stretch. In June 2025, Sitecore shipped 10.4 Update 1. We called it a very quiet drop at the time, and it was. It moved Solr from the end-of-life 8.11.2 to 9.8.1, moved Identity Server to 8.0.16 on .NET 8, and required encrypted communication with SQL Server for that new Identity Server dependency. Useful, necessary work. Maintenance, not new capability. If you upgraded to 10.4.1, you already felt the pattern Sitecore is committing to. Keep the dependencies current, keep the thing secure, don't force a big project on you every year.

10.5 landed on August 5, 2026. Look at what it carries and the pattern holds.

What actually shipped in 10.5

The platform support story is the headline, and it matters more than it sounds. 10.5 supports Windows Server 2025, SQL Server 2025, and Solr 10. SQL Server 2019 support is gone, so if you're still on it, that's an upgrade you have to plan. Solr 10 brings mandatory Basic Authentication, so that's a config change, not a drop-in swap.

Here's why the support matrix is the point and not a footnote. Sitecore deliberately timed this release to pick up the newest stable dependencies, and said as much in the release webinar. Part of the reason 10.5 shipped in August rather than earlier was to include Solr 10, which came out in March, so the platform lands on the freshest supported search engine. The stated goal is to give you a much longer runway before the next infrastructure-driven upgrade, so you're not forced into a Solr 11 jump halfway through the support cycle. Sitecore can't promise you'll never touch a dependency again, but that's the intent behind the timing.

The UI got a refresh. New branding, updated typography and color, better contrast, spacing cleanup. Everything is where it was. There's no retraining cost here, and there's no big new editing surface either. It's a coat of paint and some real accessibility work, and that's all it's meant to be.

Identity Server moved forward again, and this one has a deadline attached. Sitecore shipped Identity Server 9 as its own module, now built on .NET 10, and it supports instances back to 10.3. The reason to care about the timing is the calendar underneath the previous version. Identity Server 8 runs on .NET 8, and Microsoft support for .NET 8 ends in November 2026. In the release webinar, Sitecore pointed to that same November date as the reason to move off Identity Server 8, since it runs on .NET 8. If you run XP, getting onto Identity Server 9 before November is a real do-this-now item, whether or not you take the full 10.5 upgrade. The new version also adds Azure Entra support for SQL authentication, which teams have been asking for. As for Publishing Service, Sitecore said in the webinar that the next version will run on .NET 10 and ship with the 10.5 wave. The current Publishing Service on the portal is the 8.0 line, which runs on .NET 8, so treat the .NET 10 build as forthcoming rather than done.

Two changes will bite developers who don't read the notes. I already mentioned the Package Installer and Package Designer being off by default. A single setting, Sitecore.Packages.Disabled, is true out of the box, and you re-enable packages with a supplied patch config. Sitecore recommends running with it disabled most of the time, since the installer lets you upload code and that's an attack surface you don't want open on a production content-management server. The other one is that the built-in GraphQL Playground has been removed. Point Postman, Insomnia, or GraphiQL at your GraphQL endpoint instead. Neither change is a problem once you know. Both will cost you an afternoon if you don't.

Those two are the ones people trip over, but they aren't the whole list. The breaking-changes page for 10.5 is substantial. Telerik got a major version bump, BinaryFormatter was replaced with a JSON-based format for security reasons, and there are messaging database and other changes underneath. Read that page for the platform and for every module you run before you scope the work. The rest of the release is the accumulated security, performance, and reliability fixes that build up between versions. That's the bulk of it, and it's the least glamorous and most valuable part.

On the module side, a couple of things shipped around the same window that are worth knowing if you run them. These are separate module releases on their own cadence, not part of the XP 10.5 package. Sitecore Stream can now translate a whole item tree in one pass instead of one item at a time, which is a real time saver on multi-page sections and campaign sites. Stream also respects your field validation rules now, so when you ask it to generate a variant, it won't hand you a call to action that blows past your character limit. Pathway, the migration tooling for teams moving toward SitecoreAI, picked up a 1.4 release. It pulls from an external website by scraping, with the crawler handling up to 200 URLs and bringing media across. How much it captures depends on what the source site exposes to a crawler.

About the AI question

People keep asking whether 10.5 has AI in it. The honest answer is no, not in the platform itself. XP 10.5 has no AI baked into the core product. The AI you can put next to it lives in the Stream module and in the connected services.

There's a naming point worth getting right here. Sitecore already ships a Marketer MCP on the SitecoreAI side, which connects agents to SitecoreAI through its Agent API. That one exists today. What Sitecore described in the 10.5 webinar is different: bringing that same agent-driven, natural-language editing to XM and XP directly, so you could point a tool like Claude at your own XM or XP instance and work with the content without being a developer. That XM and XP capability is the part that isn't out yet. The presenter was clear it's coming, not shipped.

When it does land, the workflow they described is the interesting bit. Connect an agent to your analytics and to your Sitecore instance, ask which pages dropped last week, then ask Sitecore to summarize what changed on those pages or run sentiment on them. I build MCP servers, so this is the part of the roadmap I care most about. For XP customers today, though, Stream is the direct AI extension to the platform, and the XM and XP MCP is still ahead of us.

The real story is the roadmap

Here's the thing to take away from 10.5. The release is quiet because the next stretch is not.

In the 10.5 release webinar, Sitecore laid out a longer-term plan to move XM and XP off .NET Framework and onto modern .NET. That's the multi-year project everything else is in service of. Worth being precise about the reason. The presenter was careful to say Microsoft has given no indication it's going to end-of-life .NET Framework. 4.8.1 tracks the lifecycle of the Windows it runs on rather than a fixed .NET support clock, so it isn't on a short countdown. This isn't a fire drill. Sitecore wants to get ahead of that direction, pick up the maintainability of modern .NET, and move to a faster release cadence with cleaner code underneath. Worth noting too that 10.5 itself still runs on .NET Framework 4.8.1. What moved onto .NET 10 in this release is the Sitecore Framework libraries the platform builds on, not XM and XP themselves. The full move is roadmap, not something that happened in 10.5.

The single most important promise attached to this is that you are not supposed to rebuild your website. If you run a Sitecore MVC site on a content delivery server today, that server keeps living. They can't promise zero breaking changes, but the guiding principle is protecting the site you already paid for.

The approach is worth understanding because it changes how you should plan. Sitecore is splitting the platform in two. On the rendering side, headless customers should barely feel it, and they get a lighter .NET based host that is meant to cut some hosting cost, though real savings depend on your topology. MVC customers keep their CD server, cleaned up and slimmed to just delivery. On the back office side, where most of Sitecore's own code lives, Sitecore described a strangler fig approach. A new authoring server runs side by side with today's content management server. When a new editor ships, you can keep the old one or switch. When new indexing ships, you move when you're ready. Sitecore's plan is for value to show up incrementally starting next year, with no big-bang upgrade project at the end. You just turn the old pieces off as you go.

Underneath all of that is a change in how customization is supposed to work, and this is the part that will separate the teams who have an easy few years from the teams who have a hard few years. Sitecore's direction is to prefer external customization over internal. Your code on your server, their code on their server. If there's no custom code sitting inside Sitecore's application, upgrades get close to trivial, and you get to run the thing more like a SaaS product you happen to host yourself. That's the destination they're describing. Self-hosted, but SaaS-like in how updates arrive.

On the "just move to SitecoreAI" advice

There's a message going around that the answer to all of this is to stop upgrading and move to SitecoreAI. I don't buy it as a blanket recommendation. For a lot of enterprises, the honest path is to stay on-prem, modernize in place with 10.5, and move to SitecoreAI when the timing is actually right for the business, not because a roadmap pushed them there.

That's the whole point of Sitecore protecting your MVC content delivery server and keeping your existing site compatible. For organizations that need to stay on-prem for regulatory, operational, or timing reasons, an incremental path is often more realistic than an immediate replatform. That's the shape of the work we're doing with an enterprise pharma client right now: staying on-prem while they modernize, with SitecoreAI as a later step. Where our own tooling fits in is the migration grind. We use Blink AI to cut the repetitive work when a client is ready to move. That doesn't make the approach right for everyone, but it makes staying on-prem a real option instead of a stall.

What I'd actually do now

None of Sitecore's advice here is new, and that's the point. The teams who did the hygiene work already are going to coast through this. Here's where I'd put my attention.

One timing note before you start. As of this writing in mid-August 2026, the 10.5 module rollout isn't finished. The latest SXA build on the developer portal is still 10.4, and Sitecore said in the webinar that module compatibility for 10.5 was still being verified. Confirm the modules you depend on have shipped before you kick off an upgrade. If SXA or another module you rely on isn't out for 10.5 yet, wait until the compatible release is published rather than blocking your own upgrade halfway through.

Separate your code from Sitecore's code. If you can't say cleanly which files are yours, upgrades will keep hurting. This was true five years ago and it's more true now.

Automate your deployments and your testing. I still walk into projects with no deployment pipeline and no automated QA, and it still surprises me. When Sitecore moves to a faster release cadence, and it will, manual QA on every security fix is what kills your ability to stay current. The code changes are rarely the expensive part. The re-testing is.

Stay current in small steps. In the release webinar, Sitecore characterized the breaking-change surface in 10.5 as closer to a 10.4 update than to a traditional major version, and for a clean 10.4 or 10.4.1 implementation that's a fair read. It still has real breaking changes to work through, the mandatory Solr 10 move chief among them, so it isn't zero effort. But it's a much smaller lift than dragging a 9.2 instance forward. The bigger the gap you let open, the more the eventual jump costs and the more it can break. If you're on 10.4, I'd move to 10.5.

Prefer configuration over code, and move new customizations onto your own servers now. When Sitecore rebuilds the back office, they'll handle migrations for their own features. They can't migrate a custom thing they don't know about. Every piece of logic you can push to configuration, or park on your own server instead of inside Sitecore's, is a piece you won't have to rescue later.

Be headless curious. If you're building a new campaign site or reworking a major section, look hard at headless. It's the long-term direction, and it's the easier path if SitecoreAI is anywhere in your future.

10.5 is the right kind of boring. It doesn't hand you a new feature to demo. It hands you a longer support runway, a cleaner security posture, and a clear signal about where the platform is going. The value isn't in the release notes. It's in what you do with the time this release buys you.

If you run Sitecore XP, I'm curious where you actually are on this. Have you started pulling your customizations out of Sitecore's application and onto your own servers, or is that still on the someday list? That's the work that decides how the next two years feel.

Sources: Sitecore XP 10.5 what's new and deprecated features in 10.5 (Sitecore documentation); the 10.5 breaking changes, 10.5 release notes, 10.4.1 release notes, and the SitecoreAI Marketer MCP changelog; and Sitecore's 10.5 release webinar.