Mainframe-as-a-Service
Keep your mission-critical mainframe environments running reliably while pursuing opportunities to improve, evolve and support what comes next.
Get More From Your Mainframe Today. Build More Value for Tomorrow.
Your mainframe is more than infrastructure to maintain. It underpins the applications, transactions and data your business relies on, making it one of your most important assets.
Mainframe-as-a-Service (MFaaS) helps you maximize that value, not just change who runs it. With Ensono, you can simplify operations, improve cost control and manage ongoing change with minimal disruption.
We look beyond the platform to optimize performance, ready critical applications for agentic AI, make data more accessible and identify where modernization will have the greatest impact. Our investment in next-generation talent through the Mainframe Academy helps sustain the specialist skills needed for the long term.
What to Expect When Ensono Manages Your Mainframe
Greater Control Over Cost and Complexity
Bringing infrastructure, software, capacity, licensing and specialist expertise into one managed service helps optimize mainframe costs while simplifying how the environment is managed.
For one global manufacturer, that meant reclaiming $22M a year to reinvest in technology change and innovation to adapt to their business needs.
Confidence in the Systems You Can’t Afford to Compromise
Experienced oversight, proactive operations and clear accountability help protect the critical systems your organization depends on, while giving you a reliable platform for change across mainframe, applications, data, cloud and AI.
For Fortitude Re, that meant completing a full mainframe migration to Ensono’s managed service in under five months while achieving zero downtime.
Access to Skills Without Adding Pressure
We have the mainframe expertise you need without adding to the demands on your internal teams, creating more capacity to focus on application change, data priorities and future technology decisions that your business is asking your IT teams to support.
For one state government facing key staff retirements, MFaaS reduced reliance on internal staff while giving teams room to focus on what comes next.
Freedom To Modernize On Your Terms
Choosing how your mainframe is managed today shouldn’t dictate where it runs tomorrow. Ensono helps you decide what to optimize, evolve or modernize based on your business priorities, so you can move at the pace that makes sense for your organization.
For one major US health insurer, that meant keeping critical federal workloads on the mainframe while commercial workloads moved toward the cloud, with a MFaaS model flexible enough to support both paths.
Agility To Adapt Core Systems to Market Needs
Your critical applications don’t operate in isolation from the mainframe infrastructure that supports them. Ensono understands both, helping you make decisions across the environment, assess their wider impact and implement changes with greater confidence as market needs evolve.
For one leading auto parts retailer, that meant modernizing critical store systems while maintaining the uptime, availability and performance needed to support its growing omnichannel business.
Mainframe Managed Service Options
Choose the level of mainframe hosting, support and operational responsibility that’s right for you. Three flexible models let you follow the path that fits your mainframe strategy and move at your own pace.
Fully Managed Hosting
Hand off end-to-end responsibility for your mainframe to Ensono, with the scale, tooling and expertise to continually optimize your environment. Workloads are hosted in an Ensono data center, infrastructure ownership transfers to us, and your team has more capacity to focus on your core business initiatives.
Best for: Organizations considering a data center exit, refreshing aging technology or ready to transfer end-to-end responsibility with a cloud-like financial consumption model.
Remote Hosting
Keep your mainframe where it is and transfer ownership and day-to-day operations to Ensono. You get proven tooling and operational practices without relocating the infrastructure, changing how your mainframe is managed without changing where it runs.
Best for: Organizations ready to transfer responsibility for the platform but that want or need to keep it in its current location.
Remote Infrastructure Management (RIM)
Keep ownership and strategic control while bringing greater depth and capacity to your mainframe operations. Ensono takes on defined operational responsibilities and brings the expertise you need where you need it, easing pressure on your team.
Best for: Organizations that want help addressing skills or operational demands without transferring ownership and control.
AI and Automation Built into Day-to-Day Operations
Ensono embeds Agentic AI and automation in all its forms into mainframe operations to identify potential issues earlier, accelerate diagnosis and enable faster change. Experienced mainframe specialists provide the context, oversight and accountability needed to turn those insights into meaningful operational improvements.
The impact of this approach includes:
- Fewer major incidents
- Faster mean time to recovery
- Issues resolved before business impact
- Changes governed with operational risk controls
Transition with Confidence
A successful mainframe transition is about more than moving responsibility. It’s about protecting everything the business already depends on. Ensono brings structured knowledge transfer, proven transition processes and clear operational governance, backed by experience across complex, business-critical environments. When responsibility changes hands, your operations remain protected and the business keeps running.
“The transition to Ensono was one of the smoothest outsourcing transitions I have been apart of. Great planning and execution.”
IT Sr. Manager
$10B+ USD, Retail Industry
Gartner Peer Insights reviews constitute the subjective opinions of individual end users based on their own experiences and do not represent the views of Gartner or its affiliates.
Common Questions About Mainframe-As-A-Service
Mainframe-as-a-Service (MFaaS) combines mainframe hosting, management, and specialist support within a defined service model. With Ensono, you can select Remote Infrastructure Management, Remote Hosting or Fully Managed Hosting depending on where you want your platform to run, who should own it and how operational responsibility should be divided.
Yes. You retain the business and technology decisions that matter to your organization. The model you select determines which platform responsibilities Ensono assumes. Remote Infrastructure Management retains client ownership and greater operational control. Remote Hosting and Fully Managed Hosting progressively transfer more ownership and operational responsibility to Ensono.
Yes. With Remote Hosting, the platform remains in your data center while ownership and day-to-day management transfer to Ensono. With Remote Infrastructure Management, you retain ownership of the platform and facility while Ensono assumes defined operational responsibilities.
Yes. Your operating model can evolve as your workforce, data center plans and modernization priorities change. We can help you transition from Remote Infrastructure Management to a hosting model using a structured approach designed to maintain service continuity and minimize disruption.
Beyond day-to-day operations, Ensono can help identify opportunities to optimize software and capacity, modernize development practices, connect applications and data through modern integration approaches, and determine which workloads should be improved in place or considered for migration.
Ensono uses AI and automation to correlate operational signals, identify abnormal conditions, accelerate diagnosis and support governed remediation. Mainframe specialists provide operational context, oversight and accountability for service outcomes.
Ensono has over 30+ years of experience and has mastered the transition of mainframe environments from in-house management or incumbent providers. We have a proven transition approach designed to minimize disruption while maintaining service continuity.
Security, compliance and disaster recovery requirements are incorporated into the agreed MFaaS model. Controls, monitoring, oversight, recovery objectives, testing and responsibilities are defined according to the selected service and your organization’s requirements.
Yes. MFaaS provides a stable operating foundation while giving you the flexibility to determine the right future placement for your mainframe workloads. You can optimize applications on the platform, modernize development and integration, make mainframe data more accessible, or selectively move workloads based on what’s right for your organization.
When comparing MFaaS providers, look beyond infrastructure and price. Evaluate their delivery models, transition approach, mainframe and hybrid IT expertise, operational resilience, Agentic AI and automation capabilities, proof points of continuing optimizations, skills strategy, cost transparency and commercial flexibility. You should assess whether the provider offers clearly defined responsibilities and governance while giving you a practical way to adapt the service as your requirements change
Client Success with Mainframe-as-a-Service
Case Study
Cost-effective Mainframe Helps Revitalize Large US Retailer
Learn how Ensono provided a Remote Hosted Mainframe-as-a-Service solution tailored to the client’s specific needs.
Case Study
Modernizing Mainframe Ops for Global Financial Stability
Discover how Ensono helps a top-tier financial services firm ensure 99.999% availability, modernize 125K MIPS operations, and expand secure, automated resilience.
Case Study
Health Insurer Future-Proofs Mainframe and Saves $50M with Ensono
See how Ensono helped a leading health insurer reduce mainframe costs by 40% and save $50M over five years, ensuring scalability and business continuity with Mainframe-as-a-Service.
Mainframe-as-a-Service Resources
Check out some of our latest resources now.
Analyst Report | Inside Ensono
Ensono recognized as a Leader in 2026 ISG Provider Lens™ Mainframe – Services & Solutions
Guide | Industry trends
Get Clarity on the True Cost of your Mainframe
Make your next mainframe decision count
Choose the Mainframe-as-a-Service model that meets your operational needs today, with the expertise and flexibility to create lasting value and respond to what comes next.