SIEM market guide 2026

A SIEM, short for security information and event management, is the system a security operations team watches all day. It collects logs from across the organisation, stores them, connects related events and runs detection rules that raise alerts when something looks like an attack. It is also where analysts search during an investigation and where most compliance reports come from.

Almost every organisation with a security operations centre runs one. The questions now are which kind to run and how much data to send it.

What the numbers say

Teams still believe in the SIEM. In Sumo Logic's 2025 security operations survey, nine in ten respondents said the SIEM approach is still relevant for protecting their organisation. Many are unhappy with the one they have. In the same survey 73% of security leaders said they were reassessing their SIEM, half reported difficulty fitting a legacy SIEM into the rest of their technology, and 75% of those confident in their current SIEM were still looking at alternatives.

Results are mixed. In Sumo Logic's January 2026 report, 52% of security operations leaders were very confident their SIEM could scale to future needs, and 51% said it was very effective at cutting the time to detect and respond to threats. The CardinalOps 2025 State of SIEM report found that SIEMs collect enough telemetry to detect more than 90% of MITRE ATT&CK techniques, yet miss 79% of the techniques adversaries use, because detection rules are still written and tuned by hand.

Most of these surveys come from SIEM vendors, so treat them as a picture of buyer mood.

What a SIEM does

Collection and storage come first. The SIEM receives logs from firewalls, endpoints, cloud services, identity providers and business applications, and keeps them for search and for compliance.

Correlation connects events that mean little alone. A login from a new device followed by a large download from the same account can add up to one alert.

Detection rules turn that data into alerts. Most SIEMs ship with a library of rules mapped to MITRE ATT&CK, and teams add their own.

Investigation happens in the same place. Analysts search the stored logs to work out what happened and how far it went.

Response is increasingly built in. Many SIEMs now include SOAR, security orchestration, automation and response, which runs playbooks for routine steps such as blocking an address or disabling an account.

How the market is changing

The SIEM is moving to the cloud. Most new deployments are software as a service, priced by the volume of data taken in, which is why so many teams now put a security data pipeline in front of the SIEM to send it less.

The SIEM is also becoming part of larger platforms. Endpoint and network security vendors now sell their own SIEM alongside their other products, and some bought their way in. Palo Alto Networks took over IBM's QRadar SaaS business in September 2024 and offered QRadar customers a move to its own platform.

AI is now a buying criterion. In Sumo Logic's 2025 survey, 90% of security leaders called AI a key driver when choosing a SIEM or an alternative, and 70% said AI shapes their trust in current and future SIEM products. 34% of respondents said AI playbooks had cut their average incident response time. Teams also want the SIEM to watch AI itself. In Exabeam's September 2026 research, 56% of security leaders said they extend their existing SIEM, detection or monitoring tools to monitor AI agents.

What to check before you buy

Start with data cost. Ask for a price at your real daily log volume and at the volume you expect in two years, and find out what happens to the bill if a new source doubles it.

Check detection content. Ask how many detection rules come with the product, how they map to MITRE ATT&CK and who keeps them up to date. Then test them against your own data.

Look at integrations. In Sumo Logic's 2025 survey, 85% of security teams called built-in threat intelligence essential and 84% rated built-in SOAR as important or extremely important.

Think about leaving before you join. Of those weighing new options in the same survey, 95% named flexibility as critical. Find out whether you can export your data and rules in an open format, and whether the product accepts data from a pipeline you control.

Run a proof of concept on your own logs. A few weeks with your two noisiest sources shows the real data volume and the alerts you would get.

Who sells SIEM

The market has two groups. Specialists sell the SIEM as their main product. Larger security and technology companies sell a SIEM as part of a wider platform.

Who owns them

Ownership changed hands at the top of the market. Cisco agreed to buy Splunk for about $28 billion in September 2023. Francisco Partners took Sumo Logic private for about $1.7 billion in 2023. In 2024 Thoma Bravo merged LogRhythm with Exabeam, and Palo Alto Networks bought IBM's QRadar SaaS business. In June 2025 Securonix bought ThreatQuotient, a threat intelligence company.

For buyers this means fewer independent choices and more SIEMs tied to a wider platform. It is worth asking each vendor how its roadmap depends on its owner.

Who funds them

New entrants are still raising money. Cylake raised a $45 million seed round in March 2026 and $245 million more in September 2026, before releasing its product. Abstract Security raised $25 million in July 2026.