According to the Forrester Total Economic Impact (TEI) study commissioned by Microsoft, organizations that adopt Microsoft Defender, including Sentinel SIEM capabilities, see both cost savings and performance gains in their security operations.

For a composite retail organization with 10,000 FTEs and $5 billion in annual revenue, Forrester modeled the following three-year, risk-adjusted outcomes:

• $17.8 million in total quantified benefits vs. $5.2 million in costs.
• $12.6 million net present value (NPV).
• 242% ROI with a payback period of about 6 months.

The key drivers behind these results include:

• Vendor consolidation: A 60% reduction in costs tied to decommissioning legacy agents, on-premises hardware, and overlapping security tools, leading to about $12 million in multicloud security savings.
• SecOps efficiency: An 80% reduction in incident response effort, with fewer false positives and more actionable alerts, contributing roughly $2.4 million in optimization benefits.
• Lower SOC engineering overhead: Improved automation and low-code workflows reduce reliance on specialized engineering and external contractors, saving about $513,000.
• Reduced breach impact: Better visibility and faster response help cut the cost of external attacks by 75%, avoiding an estimated $2.8 million in breach-related costs.

Operationally, organizations report that Microsoft Defender helps them reimagine their SOC as a more unified, AI-assisted operation, with analysts spending less time on manual triage and more time on proactive security work.

The TEI study highlights that Microsoft Defender, built on Sentinel’s data lake, graph, and SIEM capabilities, reshapes daily incident response by automating routine tasks and improving context for analysts.

Organizations in the study reported:

• Mean time to acknowledge (MTTA) incidents dropped from about 30 minutes to 15 minutes.
• Mean time to resolve (MTTR) went from up to 3 hours to less than 1 hour in many cases.

This improvement comes from:

• Native integrations and signal correlation that provide richer, out-of-the-box context for alerts.
• Fewer false positives, so analysts spend less time chasing noise.
• Embedded threat intelligence and AI-driven assistance that guide investigation and response steps.
• Automated workflows that standardize containment and remediation without requiring specialized coding skills.

One CISO in financial services noted that the time to detect, investigate, and resolve incidents “reduced quite significantly,” allowing analysts to meet SLAs more consistently and free up capacity for additional tasks instead of constant firefighting.

Overall, Defender helps teams move from reactive incident handling to more proactive, engineering-driven security operations, while reducing burnout and improving collaboration across SecOps roles.

Forrester’s composite enterprise model provides a useful reference point for understanding the cost and effort profile of a Microsoft Defender deployment.

Three-year, risk-adjusted cost breakdown:

• Licensing: About $5.1 million for Microsoft Defender for Cloud and E5 security licenses for 10,000 FTEs, plus Sentinel SIEM data ingestion. The composite organization ingests 1 TB/day of security data in Year 1, scaling to 2 TB/day by Year 3, with 25% of data retained in auxiliary logs.
• Deployment and training: Approximately $109,000 over three years. The rollout starts with Sentinel and then adds other Defender capabilities, taking about six months to fully deploy, with a focused three-month deployment and training phase up front.
• Ongoing administration: Around $20,000 over three years, assuming up to 2 hours per month of dedicated management effort.

Implementation approach:

• Begin with Sentinel as the central SIEM and data lake.
• Gradually onboard additional Defender capabilities to avoid disruption.
• Provide initial and ongoing training so analysts and engineers can take advantage of automation, detection-as-code practices, and unified workflows.

When weighed against the modeled $17.8 million in benefits over three years, these costs result in a 242% ROI and a payback period of about six months for the composite organization. While actual numbers will vary by environment and scale, the study suggests that a unified Defender and Sentinel platform can offset its costs through vendor consolidation, reduced incident response effort, and lower breach exposure.