How to control Microsoft Sentinel costs without cutting corners

As Spider-Man’s uncle (twice) said: With great power comes great responsibility.

Microsoft Sentinel gives you serious power. But it definitely needs some responsible management.

It pulls in data from everywhere, flags everything, and before long you could be racking up unwanted ingestion costs.

But responsibility doesn’t mean holding back. With the right approach, you can unlock Sentinel’s full potential and keep costs under control.

That’s exactly what we explored in our Microsoft Sentinel cost saving masterclass, sharing practical ways to fine-tune ingestion, cut wasted spend, and make Sentinel work smarter, not louder.

Here’s what we revealed.

Cost transparency in Microsoft Sentinel is your secret weapon

It’s tempting to ingest every log, but at £2.46 per gigabyte, it’s an easy way to burn through budget fast. Plus, it’s counterproductive. Visibility is crucial, of course, but not all logs deliver equal security value.

Time and again do we see teams pulling in legacy data, noisy streams and low-value events that add nothing. The key is precision, not volume.

And the reality is that Sentinel deployments which apply targeted strategies achieve significant savings and more accurate security analysis.

Three ways to optimise Sentinel data ingestion costs

• Remove low-value logs: Discontinue ingestion of logs that don’t directly relate to actionable security insights or essential compliance.
• Optimise Data Collection Rules (DCRs): Use DCRs to filter out redundant fields and low-priority events before ingestion.
• Monitor ingestion anomalies: Proactively identify unusual data spikes from misconfigurations or new workloads to avoid unexpected costs.

Unlock substantial savings with auxiliary logs and smarter tiering

Costs spiral when data sits unnecessarily in Sentinel’s analytics tier. However, by tiering your data appropriately you can see significant reductions in these costs.

• Commitment tiers: Using commitment tiers in Log Analytics can reduce analytics-tier ingestion costs by up to 30% compared to pay-as-you-go.
• Auxiliary logs: Ideal for high-volume, low-value data, auxiliary logs are significantly cheaper than analytics-tier logs, offering substantial storage cost savings.
• Archive tier and long-term retention: Offloading older logs to the archive tier reduces costs significantly without compromising compliance or visibility.

By carefully allocating logs between analytics, auxiliary, and archive tiers, organisations regularly achieve cost reductions of 30% or more without losing critical visibility.

Of course, this isn’t something to approach with a blunt instrument. Moving data across tiers requires care, planning, and timing. Get it wrong and you risk breaking detection logic, losing investigative fidelity, or creating blind spots in your threat model. Done right, with a clear understanding of your detection dependencies and investigative needs, and the savings will follow.

Start by identifying which logs support your key detections and compliance needs. Review them with your SOC team and test any changes in a safe environment before making the switch.

The goal is to keep what’s useful, trim what isn’t, and avoid surprises later.

Don’t leave money on the table: Microsoft’s hidden cost-saving tools

Are you claiming all the ingestion grants that you’re entitled to within your existing Microsoft licences?

A lot of organisations aren’t. Which means they’re paying more than they need to be.

If you’re on Microsoft 365 E5 or Defender for Server P2, it’s highly likely you have access to:

E5 data grant

Organisations leveraging Microsoft 365 E5 licences can save thousands monthly through built-in data ingestion allowances. Surprisingly, many remain unaware of this straightforward saving.

Server protection savings

Sentinel customers using Defender for Server Plan 2 receive free ingestion up to 500MB per server daily. For mid-sized deployments, these savings can quickly reach meaningful sums.

This is free money. Be a shame to waste it, wouldn’t it?

Microsoft Sentinel cost optimisation is a process not a project

Here’s what most teams get wrong: they treat Sentinel cost optimisation as a one-off project. Fix it once and move on.

It doesn’t work that way.

Cost control is an operating discipline. A process that needs ongoing attention, regular reviews, and someone who understands both the technology and the business impact.

That’s why managed services like Kocho’s XDR Rapid Protect deliver:

• Continuous log and data governance
• Smart ingestion modelling that adapts to your needs
• Cost monitoring and budget protection that works while you sleep

You really don’t have to figure this out alone. The teams that get Sentinel cost control right usually use the right people, with the right experience to help make the right decisions.

Managed correctly Sentinel should deliver best-in-class security and cost-efficiency to your SOC

The difference between cost-effective and wasteful Sentinel deployments comes down to intent. The teams getting the best results know exactly what they need to see.

And what they don’t.

They tune for relevance, not volume.

Start with your risks. Keep what gives you real insight. Drop what doesn’t. Review your tiers, refine your rules, and cut the noise without cutting coverage.

If you missed the webinar, Microsoft Sentinel cost saving masterclass, then hit the link below and watch the full video. It’s full of clear, actionable guidance for making Sentinel work harder without spending more.

And if you want to find out how Kocho’s managed security services are helping organisations stay protected without unnecessary costs, speak to our team today.

Microsoft Sentinel cost saving Q&A

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