Single-factor authentication (often abbreviated as SFA) means verifying a user’s identity with just one factor. Most commonly, it’s logging in with a username (email) and password.
- This is the simplest and most common login method, but it’s also the least secure and depends heavily on users’ password hygiene.
- If someone steals or guesses the password, they can easily access the account.
- That’s why many businesses switch to multi-factor authentication (MFA), which combines multiple factors for a significantly higher level of security.
What single-factor authentication means for businesses
1. Employee onboarding
- With SFA, new hires usually get just a username and password for company systems, apps, or Wi‑Fi.
- HR or IT should deliver these credentials securely and document them properly.
- Risk: weak, reused, or leaked passwords let attackers get in quickly.
2. Employee offboarding, revoking passwords and access
- Storing passwords in spreadsheets, notes, or on paper is a serious security risk.
- If accounts aren’t disabled when someone leaves, former employees might still sign in.
- Have a clear offboarding checklist: reset or revoke passwords and disable accounts immediately.
3. Tracking passwords and access
- Keep an up-to-date inventory of who has access to each system and how each account is protected.
What are the pros and cons of single-factor authentication
Advantages of single-factor authentication
- Simplicity and convenience – users only remember a password, no extra apps or hardware tokens.
- Fast onboarding – IT/HR creates an account, shares the password → the employee can start right away.
- Low cost – no need for mobile authenticator apps, SMS gateways, or hardware security keys.
Risks of single-factor authentication
- Security relies solely on the password. Strong, unique passwords and good password hygiene reduce risk, but do not eliminate it.
- Human factor – in practice, people often reuse or write down passwords.
- Audits and accountability – it’s harder to prove who logged in, since knowing the password is enough.
How to use single-factor login securely
Username-and-password sign-in can be sufficient for small and midsize businesses if clear policies are enforced:
- Strong passwords and enforced password policy (complexity, rotation/change cadence, etc.)
- Employee security awareness training
- Password disablement or reset during offboarding
- Ability to centrally change or reset user passwords
- Additional protection for the company network from external threats (for example, private cloud or VPN)