TIA Portal V21: What's New, Who Should Upgrade and How to Learn It Free

TIA Portal V21's main new features are SIMATIC Source Documents (SIMATIC SD), a text export that lets PLC code live in Git, a next-generation WinCC Unified screen editor, redundant WinCC Unified SCADA servers, and SINAMICS S220 servo support in Startdrive. Projects from V14 onwards upgrade directly. You can learn it free with Siemens' trial and a simulator.

Checked 1 October 2026. Every feature below comes from Siemens' own press release, its V21 technical slides or its V21 update documents, listed under Sources.

When was TIA Portal V21 released?

Siemens announced TIA Portal V21 on 11 November 2025 at the SPS trade fair in Nuremberg. Siemens' press release leads with three themes: version control with tools such as Git, higher availability for WinCC Unified SCADA, and the WinCC Unified Data Hub for long-term plant data.

V21 also changes how fixes arrive. Siemens no longer ships service packs. Alongside the scheduled updates it now issues hotfixes for critical security and stability problems, and the version number tells you which you have: 21.0.0.0 is the release, 21.0.0.1 is the first hotfix, 21.0.1.0 is Update 1 and 21.0.1.1 is a hotfix on top of Update 1. Siemens' readme for the V21 updates was published in April 2026. Updates are cumulative, so you do not have to install them in sequence.

What is SIMATIC SD, and does V21 really work with Git?

This is the change most engineers have waited for, and it is worth being precise about it. V21 does not put a Git client inside the editor. It adds SIMATIC Source Documents, a new export format. Siemens describes it as source code only, text-based, human-readable and version-independent, and says it carries no internal meta information. Graphical code becomes text: a ladder rung is written out as RUNG, Contact and Coil statements that you can read in any text editor and compare line by line.

Siemens lists these objects as supported:

• LAD and F-LAD, FBD and F-FBD, SCL, and mixed-language blocks
• Data blocks and PLC data types (UDTs)
• Project libraries
• Multilingual comments

You can reach the format through TIA Portal Openness (the API) and through the Version Control Interface (VCI). In VCI, SIMATIC SD sits alongside the older SimaticML (XML) export. Each VCI workspace can now have its own export format, and that setting is saved with the workspace, so a team can share it.

Why it matters: SimaticML exports were XML full of internal IDs. A one-line logic change produced a noisy diff and merge conflicts that nobody could resolve by eye. A text format with no meta data makes Git diffs, code reviews, pull requests and continuous integration practical for PLC code. Siemens also says the syntax is independent of the TIA Portal version, so a repository can stay usable across versions.

If you already write SCL, you have a head start. SCL was always text, and the free SCL Structured Text course teaches the habits (small blocks, clear interfaces, comments) that make a repository readable.

What changed in WinCC Unified?

• Next-generation screen editor. Siemens says the new editor previews screens without compiling, downloading or starting runtime simulation. It also gives a WYSIWYG view, snap functions, polyline editing and zoom and pan shortcuts, and it lays the ground for responsive design. It covers Unified Basic, Comfort, Edge and PC runtimes.
• Redundant servers. WinCC Unified SCADA applications can now run on a redundant server architecture for continuous operation.
• WinCC Unified Data Hub. The Data Hub is now on general release. It is a central archive for production data, alarms and audit trails from several WinCC Unified PC runtimes, kept over long periods.
• Smaller additions. These include an Alarm Indicator screen object, configurable limits and thresholds, real-time MQTT data transfer for PC runtime, process screens on several monitors at once, and reporting in the engineering system.

If you are moving from WinCC Comfort or Advanced panels, the free WinCC Unified course builds a full Unified project in PLCSIM Advanced. It covers the screens, faceplates, alarms and scripts that carry over to V21.

What changed for drives and motion?

Startdrive V21 adds the SINAMICS S220 multi-axis servo system. Its other changes save commissioning time:

• Background download. After a configuration download the drive restarts, and the TIA Portal interface no longer locks while it does. Siemens says this works for CU3x0-2 based drives and all drives from firmware V6.x, and is on by default.
• Parameter compare now takes one reference drive object and up to four others at once, online or offline. You can export the result to CSV.
• Mass firmware upgrade changes the firmware version of several drives in the offline project in one action. It does not change the firmware on the device itself.
• Redundant PLCs. G220, S120 and S220 drives can now connect to S7-1500 R/H controllers with S2 redundancy.

For motion control, Siemens lists multicore support on the T-CPU and new IPC and Open Controller hardware for technology CPUs. The free SINAMICS drives course covers G120 and S120 commissioning in Startdrive, which is the right base before S220.

What else changed in STEP 7?

• Keep DB values on structural changes. On S7-1500 CPUs with firmware 4.1, you can add new variables at the first level of an optimised data block and download without losing the actual values. Before, you had to take a snapshot and restore it.
• S7-1200 G2 is supported, including the fail-safe variant.
• Help. The old Windows-based help viewer has been removed. Local help now opens in the browser-based viewer.
• Openness. The API architecture was redesigned for long-term stability. Siemens says the behaviour of existing applications is unchanged, and that TIA Portal and Openness rely on .NET Framework 4.8.

Who should upgrade to V21, and who should wait?

Upgrade now if:

• You start new projects, especially on S7-1500, S7-1200 G2 or WinCC Unified. There is no reason to begin a new machine on an older version.
• Your team wants version control. SIMATIC SD is the first Siemens export format that makes Git diffs readable. That alone justifies a pilot project.
• You use S220 servos or WinCC Unified redundancy, because those need V21.

Wait, or upgrade a copy first, if:

• A machine is mid-commissioning or under warranty on an older version. Finish the job on the version the customer accepted.
• Your customer specifies a version. OEMs and end users often fix the TIA Portal version in the contract, and the upgraded project is a V21 project from then on.
• You depend on third-party libraries or add-ins that have not yet been released for V21.

How do I upgrade an older project to V21?

Siemens' V21 slides give the route. Projects from V14 onwards upgrade directly to V21. Projects older than V14 go through V13 SP1 or SP2 first, then V14 to V20 (Siemens recommends V20), then V21. Classic STEP 7 projects from SIMATIC Manager are migrated into V14 to V20 with the migration tool, then upgraded. You can install V13 SP1/SP2 up to V21 side by side, and the slides say a V21 licence covers all versions from V11. For many projects at once, Siemens offers a Project Upgrader built on TIA Portal Openness.

Windows and PC requirements

TIA Portal runs only on 64-bit Windows. Siemens publishes the supported Windows editions, RAM and disk requirements in the readme for each version, and lists change between versions. Read the V21 readme on Siemens' download entry before you upgrade a work laptop, and check with your IT department if the laptop is centrally managed. We have not listed the editions here because we could not confirm them on a Siemens page that opens without signing in.

How can I learn TIA Portal V21 for free?

Siemens offers a time-limited trial of STEP 7, WinCC and S7-PLCSIM for registered users. Our TIA Portal free trial guide explains what it includes and how to get it. With the trial and PLCSIM you need no hardware at all.

A free route through V21, in order:

1. [Siemens TIA Portal](/free/siemens-tia-portal), for absolute beginners. It goes from an empty project to an S7-1200 program with timers, counters, analog scaling, function blocks and a WinCC screen, all in simulation. It is written for V17 or later, so V21 is fine.
2. [Siemens SCL Structured Text](/free/siemens-scl-structured-text-tia-portal). Text-based code is what SIMATIC SD and version control reward.
3. [Siemens WinCC Unified](/free/siemens-wincc-unified), for the HMI and SCADA side of V21.
4. [SINAMICS drives with Startdrive](/free/siemens-sinamics-drives-starter-startdrive), before you meet an S220.

The Siemens engineer path puts these and more in order. If you want to see V21 running first, the first S7-1200 program walkthrough builds a small program from scratch.

Practise version control on your own

You do not need a team to try SIMATIC SD. Export one function block from a practice project with VCI, commit it to a local Git repository, change one rung, export again and look at the diff. Ten minutes of this shows you why the format matters, and it gives you something real to talk about in an interview.

Every EDWartens course is free to study. An optional EDWartens Certificate of Completion, from US$2.99, is issued after you pass the final assessment, and anyone can check it at edwartens.com/verification. It is not a Siemens certification.

Take the free course

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Siemens SCL Structured Text in TIA Portal

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Siemens SINAMICS Drives: G120 and S120 with STARTER and Startdrive