What Is a Passkey? A Simple Guide to the Future of Passwordless Security
Imagine logging into your business accounts without having to remember another password.
No forgotten passwords. No reused credentials. No typing a security code into a website after clicking a link in an email.
That’s the idea behind passkeys, and they’re becoming an increasingly important part of how we securely access our online accounts.
In April 2026, the UK’s National Cyber Security Centre (NCSC) went further, announcing that it would begin recommending passkeys wherever services support them.
So, what exactly is a passkey? How does one work? And should businesses be thinking about making the switch?
Here’s our straightforward guide.
What Is a Passkey?
A passkey is a secure way of signing into an account without using a traditional password.
Instead of entering a password, you confirm that it’s you using something you already use to unlock your device, such as:
- Your fingerprint
- Facial recognition
- Your device PIN
You may already have encountered passkeys when logging into services through your smartphone or computer without even realising it.
The technology is built on the FIDO2 authentication standard and uses cryptography to verify your identity securely.
Put simply:
- A password is something you have to remember and type.
- A passkey is a digital credential securely stored and accessed through your device or credential manager.
For the user, that can mean a quicker and much simpler login.
Behind the scenes, however, something far more secure is happening.
How Does a Passkey Work?
When you create a passkey, two cryptographic keys are created.
One is a public key, which is stored by the website or service.
The other is a private key, which remains protected by your device or credential manager.
When you try to sign in, the service asks your device to prove that it holds the correct private key.
You then approve the request using your usual device security, such as:
Face ID → Fingerprint → Windows Hello → PIN
The private key itself isn’t sent to the website.
This is an important difference from passwords.
With a traditional password, you’re entering a piece of information that could potentially be stolen, intercepted or tricked out of you.
With a passkey, there isn’t a reusable password for a criminal to steal.
Why Are Passkeys More Secure Than Passwords?
Passwords have been part of computing for decades, but they come with some very human problems.
People forget them.
People reuse them.
People choose weak ones.
And unfortunately, people can be tricked into giving them away.
Passkeys help remove several of those risks.
1. They’re Resistant to Phishing
This is perhaps the biggest benefit.
A cyber criminal might create a convincing fake Microsoft 365 login page and trick someone into entering their email address and password.
They could potentially even convince them to enter a traditional authentication code.
Passkeys work differently because authentication is cryptographically linked to the genuine service.
That makes them resistant to the phishing techniques commonly used to steal passwords and traditional MFA credentials.
The NCSC now assesses FIDO2 credentials, including passkeys, as being as secure or more secure than traditional MFA against common credential attacks.
2. There’s Nothing to Remember
We’ve all been there:
Incorrect password.
Try again.
Still incorrect.
Reset password.
Wait for email.
Create another password you’ll probably forget…
Passkeys remove much of that frustration.
You simply use the same security method you already use to unlock your device.
That can make secure authentication easier rather than harder.
3. They Can’t Be Reused Between Accounts
Password reuse remains a major security problem.
If somebody uses the same password across several accounts and one service is compromised, criminals may try those credentials elsewhere.
Each passkey is unique to the service it was created for.
There’s no single password that can be copied and tried across multiple websites.
Passkeys vs Passwords vs MFA
So where does this leave multi-factor authentication?
Traditional MFA remains an extremely important security measure, particularly where passkeys aren’t available.
But passkeys can provide a different approach.
A traditional login might look like:
Username → Password → Authentication code → Login
A passkey login could simply look like:
Account → Face, fingerprint or PIN → Login
Where user verification is required, FIDO2 authentication can itself constitute multi-factor authentication because it combines possession of the cryptographic credential with the method used to verify the user.
That can mean stronger security with less friction for the person logging in.
What Happens If I Lose My Phone or Laptop?
This is understandably one of the first questions people ask.
If your passkey is on your phone, what happens when your phone disappears?
Passkeys can be stored in different ways.
Some are device-bound, meaning they’re stored on a particular device.
Others can be securely synchronised through supported credential managers, allowing them to be available across multiple trusted devices.
For example, Microsoft supports synchronising passkeys across Windows devices through a Microsoft account.
Businesses still need to think carefully about:
- Device security
- Account recovery
- Access controls
- Removing lost or compromised devices
- Managing employee access when someone leaves
Moving away from passwords doesn’t mean moving away from good IT management.
What Do Passkeys Mean for Microsoft 365?
This is where passkeys become particularly relevant for many of the businesses we support.
Microsoft is continuing to expand passwordless authentication across its ecosystem.
Microsoft Entra ID currently supports both synced and device-bound FIDO2 passkeys as authentication methods.
Depending on how an organisation’s environment is configured, users may be able to authenticate using technologies including:
- Windows Hello
- Microsoft Authenticator
- FIDO2 security keys
- Supported passkeys and credential managers
However, work and school accounts are controlled by the organisation, so businesses need to make sure authentication methods are introduced and managed appropriately rather than simply leaving security decisions entirely to individual employees.
Should Your Business Stop Using Passwords?
Not necessarily overnight.
Passkey adoption is growing, but not every website, application or business system supports them yet.
The NCSC’s current advice is straightforward:
Where passkeys are available, choose them.
Where they’re not available, businesses should continue using strong, unique passwords alongside appropriate two-step or multi-factor authentication.
For most organisations, moving towards passwordless authentication will therefore be a gradual process rather than a switch that happens overnight.
5 Things Businesses Can Do Now
You don’t need to overhaul your entire IT environment tomorrow.
Instead, start with the basics.
1. Review How Your Team Logs In
Understand which systems employees use and how they’re currently authenticated.
2. Make Sure MFA Is Enabled
If passkeys aren’t available, strong multi-factor authentication remains an important layer of protection.
3. Check Where Passkeys Are Supported
You may find that services your business already uses are beginning to offer passkey authentication.
4. Review Your Microsoft 365 Security
Look at user permissions, authentication methods, devices and your wider Microsoft 365 configuration.
5. Keep Educating Your Team
Technology alone can’t solve every cyber security challenge.
Staff should still understand phishing, suspicious login requests, social engineering and how to report something that doesn’t look right.
The tecdesk View
At The tecdesk, we believe good cyber security shouldn’t make people’s jobs unnecessarily difficult.
In fact, passkeys are a great example of how technology can potentially do the opposite.
They can make logging in simpler for employees while making it significantly harder for criminals to steal and reuse credentials.
But like any new technology, implementation matters.
Businesses still need appropriate security policies, secure devices, access controls, recovery processes and support.
It’s not simply about removing passwords.
It’s about creating a more secure and practical way for people to access the technology they need.
Final Thoughts
Passwords aren’t disappearing tomorrow, but the way we log into business systems is changing.
Passkeys offer a glimpse of a future where authentication can be:
✔ Easier for employees
✔ Harder for criminals
✔ Resistant to phishing
✔ Less reliant on people remembering dozens of passwords
And with organisations such as the NCSC now recommending their use where available, passkeys are something businesses should start becoming familiar with.
You don’t need to become an authentication expert.
You just need to make sure your business is moving in the right direction.
Is Your Business Ready for Passwordless Security?
If you’re unsure whether your Microsoft 365 environment is configured securely or want to understand whether passkeys and passwordless authentication could be right for your organisation, The tecdesk can help.
We can review your existing setup, authentication methods and wider cyber security to help you make practical improvements without unnecessary complexity.
Speak to our team:
No jargon. No pressure. Just straightforward IT advice that makes sense for your business.
Frequently Asked Questions
A passkey is a passwordless way of signing into an online account. Instead of entering a password, you verify your identity using your device, typically through facial recognition, a fingerprint or PIN.
Passkeys provide strong protection against common attacks such as phishing and credential reuse because there isn’t a reusable password for a criminal to steal. The NCSC recommends choosing passkeys over passwords wherever they’re supported.
Depending on how the passkey is stored, it may be synchronised securely across trusted devices or another authentication or recovery method may be available. Businesses should have appropriate recovery and device management processes in place.
Microsoft Entra ID supports FIDO2 passkeys, including synced and device-bound options. What employees can use will depend on how their organisation’s Microsoft environment and authentication policies are configured.
Yes. We can help review your Microsoft 365 environment, authentication methods, device security and wider cyber security strategy, and advise on practical steps towards stronger, more user-friendly authentication.
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