Data Security Best Practices
Learn the 20 data security practices that actually reduce breach risk.
• MFA is the single highest-impact practice. 82% of denied cyber insurance claims involved companies without it. Start here if you haven’t already
• Credential monitoring catches the #1 attack vector. Stolen passwords were involved in 22% of breaches. Dark web monitoring finds exposed credentials before attackers use them
• Cloud misconfiguration is the fastest-growing risk. As companies move data to AWS, Azure, and GCP, cloud data security best practices have become as important as network security
• Not all 20 practices are equal. Focus your budget on the ones IBM data shows save the most money: security AI, tested response plans, and credential monitoring
IBM’s 2025 report found that breaches cost $4.44 million on average. Companies with strong security controls paid significantly less.
Most best practice lists treat every item as equally important. They’re not. MFA and credential monitoring save millions per incident. A clean desk policy doesn’t.
This guide groups the 20 most important data security practices by theme and ranks them by impact.
What Are the Most Important Data Security Best Practices?
Not all security practices deliver equal value. Some save millions per breach. Others are checkbox exercises.
Data security best practices are the controls, policies, and procedures that protect sensitive data from unauthorized access, theft, and exposure. They cover access management, encryption, and monitoring. The goal is to reduce both the likelihood of a breach and the cost when one happens.
IBM’s 2025 data shows which controls matter most. Security AI and automation saved $1.9 million per breach. Tested incident response plans saved over a million. MFA blocks most credential-based attacks entirely.
The 20 practices below are grouped by theme so you can implement them in logical order. For the strategic framework that ties these practices together, see our data security strategy guide. We start with the highest-impact controls.
How Do You Secure Access to Sensitive Data?
Access controls determine who can reach your data. When they fail, attackers walk right in.
1. Enable Multi-Factor Authentication (MFA)
MFA is the single most effective security control you can deploy. Even when attackers have a stolen password, they can’t log in without the second factor. Coalition’s 2024 data found that 82% of denied cyber insurance claims involved companies without MFA.
Deploy MFA on all externally accessible systems first – VPN, email, cloud consoles. Then expand to everything. Use authenticator apps or hardware tokens, not SMS (which is vulnerable to SIM swapping).
2. Implement a Strong Password Policy
Require a minimum of 12 characters. Don’t force periodic password changes – that encourages users to rotate a single character (SuperSecret1 becomes SuperSecret2). Don’t require specific character types either.
Instead, mandate password managers company-wide. When every password is unique and randomly generated, credential stuffing doesn’t work. Check passwords against known breach data using a credential monitoring service.
3. Apply Least Privilege Access
Every user should only access what they need for their role. Fewer permissions mean less damage when credentials get compromised. Review access quarterly and remove anything unnecessary. Document all changes to make auditing easier.
Watch for permission creep – people accumulate access as they change roles but rarely lose old permissions. Automated access reviews catch this faster than manual audits.
4. Adopt Zero Trust
Zero Trust means “never trust, always verify.” Every access request gets authenticated regardless of where it comes from – inside or outside your network. Deploy micro-segmentation to limit lateral movement. Treat internal networks with the same scrutiny as external ones.
5. Monitor for Leaked Credentials
Your employees’ passwords may already be on the dark web from third-party breaches or infostealer malware. Dark web monitoring catches exposed credentials so you can force resets before attackers use them. This addresses the #1 initial access vector per the Verizon 2025 DBIR.
How Do You Protect Data at Rest and in Transit?
Even if attackers get in, encryption and proper data handling limit what they can do with what they find.
Data encryption converts readable data into an unreadable format using cryptographic algorithms. Encryption at rest protects stored data (on servers, databases, backups). Encryption in transit protects data moving between systems (over networks, APIs, email). Both are required for most compliance frameworks.
6. Encrypt Data at Rest and in Transit
Use TLS 1.3 for all data in transit and AES-256 for data at rest. This applies to API calls and database connections – not just public-facing traffic. Enable HSTS to prevent protocol downgrade attacks. Many notification laws exempt properly encrypted data from reporting requirements.
7. Classify Your Data
Not all data needs the same protection level. Classify data into tiers – public, internal, and restricted. Each tier gets different controls: who can access it and how it’s encrypted. Customer SSNs need stronger protection than your marketing blog drafts.
Classification also determines your notification obligations if that data is exposed. A breach involving classified health records triggers HIPAA requirements. A breach involving only internal memos may not require notification at all. If you don’t classify first, you can’t assess impact accurately during an incident.
8. Back Up Data Regularly
Follow the 3-2-1 rule: three copies, two different media types, one offsite. Make backups immutable so ransomware can’t encrypt them. Test restoration regularly – a backup you can’t restore from is the same as no backup.
9. Implement Secure Development Practices
Build security into your software development lifecycle. Conduct code reviews focused on security. Run static and dynamic analysis before deploying to production. Keep development, testing, and production environments separate.
Never commit credentials or API keys to code repositories. Use environment variables and secrets managers instead. Automated scanning tools like GitGuardian catch secrets before they reach public repos.
How Do You Secure Your Network and Cloud?
Network and cloud security prevent attackers from moving freely once they’re inside.
10. Segment Your Network
Divide your network into separate zones based on data sensitivity. Use firewalls between segments. If an attacker compromises one zone, segmentation prevents them from reaching everything else. Isolate critical systems in their own secure zones.
The Target breach spread from an HVAC vendor’s access point to the payment processing network because nothing blocked lateral movement. Segmentation would have contained it to one zone.
11. Configure Cloud Services Securely
Cloud misconfiguration is one of the fastest-growing causes of data leaks. Use cloud security posture management tools to monitor configurations. Never use default credentials on cloud resources. Pay special attention to IAM permissions – overly permissive roles are one of the most common paths to cloud breaches.
Cloud data security best practices include enabling detailed audit logging and automating compliance checks. Treat cloud security as ongoing, not a one-time setup.
12. Manage Your Attack Surface
Continuously track your internet-facing assets: websites, cloud resources, and shadow IT. Use automated discovery tools to find forgotten systems. You can’t secure assets you don’t know about.
Shadow IT is a growing problem. Employees sign up for SaaS tools using corporate email without IT approval. When those services get breached, your credentials leak through systems you didn’t know existed.
13. Monitor and Log Everything
Configure systems to log all activities. Collect logs in a SIEM for centralized analysis. Most web servers only log GET requests by default – make sure you capture POST requests too. Establish baseline behavior, then alert on anomalies.
The average breach takes 241 days to detect (IBM 2025). Good logging and monitoring cuts that window. When you do get breached, logs are the forensic evidence your investigation team needs to trace the attacker’s path and determine what was accessed.
How Do You Manage People and Vendor Risk?
Technical controls fail when people make mistakes or vendors get breached. These practices address the human element.
14. Train Employees on Security
Run security awareness training at least quarterly. Cover phishing recognition and proper data handling. Include business email compromise scenarios since BEC bypasses the malicious links that most training focuses on. Use real-world examples and simulated phishing tests. Focus on practical skills, not compliance slides. See our guide on human error for why training alone isn’t enough.
15. Assess Vendor Security
Your vendors have access to your data. When they get breached, you’re affected. Evaluate vendor security practices before granting access. Include security requirements in contracts. Review vendor compliance regularly. Supply chain breaches cost $4.91 million on average per IBM’s 2025 report.
Don’t just assess vendors once. Monitor their security posture continuously. Tools like SecurityScorecard provide external risk ratings. Also monitor for your vendors’ exposed credentials – a breached vendor is often how attackers reach you.
16. Secure Mobile Devices
Deploy MDM (Mobile Device Management) for company-owned and BYOD devices. Enforce device encryption and remote wipe capabilities. Restrict app installations to approved sources. Update mobile security policies as threats evolve. For remote teams specifically, see our guide to data protection for remote working.
17. Lock Down Email
Email is the primary delivery mechanism for phishing and malware. Deploy email filtering to catch the obvious threats. Use email encryption for sensitive communications. Train employees to verify unexpected requests, especially those involving money or credentials.
18. Implement Physical Security
Secure physical access to server rooms and offices with access cards and cameras. Implement a clean desk policy. Make sure physical documents with sensitive data get shredded, not thrown away. Require terminated employees to return all hardware immediately.
How Do You Respond When Things Go Wrong?
Prevention fails eventually. These practices determine whether a breach costs $2 million or $10 million.
19. Build and Test Your Incident Response Plan
Have a documented response plan that defines who does what during a breach. Test it with tabletop exercises quarterly. IBM’s data shows that companies with tested plans contain breaches faster and pay far less. A plan that sits untested is a plan that fails when you need it.
Your plan should cover containment, notification, and recovery. It should name specific people for each role, not just titles. Print it – if ransomware takes down your network, a plan stored on SharePoint is useless. See our response checklist for the step-by-step process.
20. Run Regular Security Assessments
Conduct vulnerability scanning and penetration testing at least annually. Prioritize fixes based on risk level, not just severity score. A medium vulnerability on your production database is more urgent than a critical vulnerability on an isolated test server.
Combine automated scanning with manual testing. Automated tools catch known vulnerabilities efficiently. Human testers find logic flaws and chained attacks that scanners miss. A data risk assessment ties it all together by ranking what you find by business impact.
Data security is ongoing. Threats evolve and new systems get deployed. The practices above give you the foundation. Credential monitoring fills the gap that internal controls miss by watching for your exposed passwords on the dark web.
Book a demo to see how Breachsense monitors criminal marketplaces for your organization’s leaked credentials.