New research from the Behavioural Insights Team (BIT) analyses 10 design practices that Microsoft employs to push Windows users towards Edge and away from alternative browsers, and examines how these could harm user choice.
Based on the BIT report “Dark patterns in browser choice architecture: A behavioural science perspective and their potential impact on users” (October 2026). Additional context on Microsoft’s practices comes from material provided by the BCA.
Buying a Windows PC and choosing your browser should be simple. Often, it isn’t. Before users have made or even been offered any browser choice at all, Edge is the exclusively preinstalled browser on new Windows PCs from the major PC manufacturers. That is the result of Microsoft’s ‘Jumpstart’ programme, whose terms are kept under wraps but which appears to require that Edge and only Edge be preinstalled on every PC manufacturers ship under it. What happens when a user tries to choose something different is examined in new research from the Behavioural Insights Team (BIT), a UK-based expert behavioural insights firm.
BIT was commissioned by FTI Consulting on behalf of the Browser Choice Alliance (BCA), and its analysis draws on evidence supplied by the BCA and its members.
What BIT found: dark patterns across the Windows user journey
BIT qualified 10 Microsoft practices as dark patterns across three stages of the Windows user journey: installing an alternative browser, using it for the first time, and updating the operating system. These dark patterns are design tactics that either make it harder to choose a browser other than Edge, or override a choice a user has already made. They work in three ways: by adding friction or barriers that eat into a user’s time and attention, which BIT calls “sludge and obstruction”; by making Edge seem safer or easier to use without substantiation, which BIT calls “deceptive framing”; and by pushing users to use Edge through “nudges”.
The friction starts when users go looking for alternatives. When someone searches for a rival browser, Microsoft surfaces an intrusive banner telling them to stick with Edge instead. Once an alternative is installed, clicking “Set default” in Windows Settings only switches the default browser for some web links (like http and https), while other browser-relevant file types, such as PDFs, remain with Edge.
Even when a user has set a rival browser as default, the choice often doesn’t hold. Links in Windows Search, Widgets and the Lock Screen only open in Edge, and links in Outlook and Teams head to Edge unless users find separate settings in each app. Workarounds that would have allowed a one-click switch were blocked by Microsoft in April 2023. Edge can also masquerade as the user’s chosen alternative browser by ‘stealing’ tabs from that rival browser and opening them in Edge automatically at log in, with the button to accept this experience made more prominent than the one to refuse.
And if that weren’t enough, a Windows update can put Edge straight back as the default browser. Even when users get everything set up how they like, a Windows 11 update prompt can reset their default to Edge. BIT observed that it presents the switch as “Use recommended browser settings” and the alternative as “Don’t update your settings”, with the first made more prominent. Users who don’t actively opt out have Edge reset as their default, and because updates recur, that can happen again and again. BIT finds that this creates an asymmetrical OS-level choice architecture that makes it easier for users to accept the change and revert Edge to the default browser.
What it could cost users
BIT’s analysis focuses on choices that are uneven by design. Accepting Edge is made easy while keeping your preferred browsers takes extra steps, such as opting out of a pre-selected choice in a prompt or bypassing an intrusive and salient banner appearing at the top of the Bing search results screen which tells users to stick with Edge when they seek out alternative browsers. BIT refers to these design choices as creating an “asymmetrical decision space”, i.e., one where switching to another browser feels less appealing and more difficult than continuing with Edge. BIT’s conclusion is that in these cases, choice is made “harder to act on, less transparent, or less attractive”.
Extra steps cost users time and effort. A meta-analysis of 184 field experiments, with more than 2.2 million participants, found that changing the effort needed to take an action was among the most powerful levers on user follow-through tested. For browsers specifically, a usability study found that some Windows users could not change their default or just gave up, citing “hidden or confusing settings”. And for Windows users who have overcome these barriers to choose an alternative browser, each override in favour of Edge means more time and effort getting back to where they started.
When something is made harder to find, people are more likely to end up with a choice that isn’t what they actually wanted, a harm BIT calls “loss of autonomy”, where making information harder to reach can lead people to choose against their own preferences. In a privacy experiment with 7,430 participants across six European countries, extra steps to reach key information made people around 12 percentage points more likely to choose against their own preferences. If users want to change where links open from core Microsoft productivity applications like Outlook and Teams (that initially open in Edge), they must navigate through additional “advanced settings” to make their choice. If users want to change where links and files open, they cannot simply do so in one click, instead having to navigate to settings and painfully choose their default browser individually by file and link type
Pre-selected options that apply in a user flow unless a user actively opts-out can also play a role. BIT notes that pre-selected options can support fast setup, but these can become dark patterns when they are used to hinder users’ preferences or when they are unsubstantiated. Across 58 studies, people were 27% more likely to not opt-out of the preselected option when choosing between two alternatives. That is relevant to the OS-level prompt Microsoft surfaces during the Windows update flow, which pre-selects Microsoft’s recommended settings (resetting Edge as the default browser).
Some users may be affected more than others. Time-poor users face the hassle of switching back to the browser they already chose, while older users and people with lower digital literacy may be less likely to find hidden settings or know how to put things right. The harms go beyond lost time. Unsubstantiated safety messages, a form of “deceptive framing”, and nudges that make Edge the easy option may weaken people’s ability to make informed choices. “Sludge and obstruction” that repeatedly override a user’s choice (e.g.,web links from Widgets and Windows Search ignoring the user’s default browser) may lead to “frustration and reduced trust”.
Europe changed. Most of the world didn’t.
Under the DMA, Microsoft has made several changes in the EU: users can uninstall Edge, Microsoft has committed not to show the banners urging users to stick with Edge, and changing the default in Windows 11 now updates more link and file types automatically. The situation in the EU still leaves much room for improvement, but at least EU users are better off than those in the rest of the world, where Microsoft has for the most part not made any changes to unlock user choice. BIT likewise notes that many countries outside the EU still see these patterns.
Regulators should require that Microsoft respect users’ choice
Regulators are paying attention. In the UK, the Competition and Markets Authority (CMA) published a proposed decision on 16 October 2026 to designate Microsoft as having strategic market status in respect of its business software ecosystem. In the accompanying indicative roadmap, the CMA acknowledges third-party calls to ensure that effective user choice is not undermined through Microsoft’s design of user interfaces, including negative choice architecture that steers users “towards its own products, even where users set a third-party product as a default”. Brazil’s competition authority, CADE, has also opened a dedicated antitrust investigation into Microsoft’s dark pattern practices. The BCA welcomes these developments and urges other regulators worldwide to build on this momentum.
When users choose an alternative browser and set it as their default, that choice should be respected. Regulators should protect browser choice on Windows before the same barriers take hold in newer areas such as AI. Now is the time to intervene to foster greater competition and user choice on Windows PCs. Your PC, your browser, your choice.
You can read the full BIT report here.
About the BIT report: BIT mapped evidence supplied by BCA members across the Windows user journey, from installing an alternative browser to updating the operating system, and reviewed the behavioural science literature on what such practices could mean for users. Its findings on Microsoft’s practices rest entirely on materials supplied by the BCA, and some of the practices described may apply only in certain jurisdictions. BIT used AI tools to support its literature review and drafting, with outputs verified by human researchers and subject to senior quality assurance checks.