Security basics
NIST 800-63B Password Rules: Modern Password Policy Guidelines
NIST 800-63B redefines password security by prioritizing usability and entropy over arbitrary complexity. This guide explains the modern password rules and how they align with current best practices for authentication.
1 min readUpdated: 02/16/2026Author: GeneratePasswordTo Editorial Team
Key Changes in NIST 800-63B
NIST 800-63B eliminates outdated requirements like mandatory password expiration and complex character rules. Instead, it emphasizes:
1. Passphrase Recommendations: Encouraging longer, memorable phrases over short, complex passwords.
2. User-Friendly Policies: Allowing users to choose passwords they can remember without sacrificing security.
3. Multi-Factor Authentication (MFA): Requiring MFA for high-risk systems to reduce reliance on passwords alone.
- No forced password expiration.
- Passphrases are preferred over complex passwords.
- MFA is mandatory for sensitive systems.