Picking OPC server software in 2026 comes down to one question: what's already running on your plant floor, and how far are you migrating toward OPC UA? Best overall: TOP Server from Software Toolbox for mixed-vendor plants that need one server talking to dozens of device types. Best for OPC Classic-to-UA migration: Matrikon OPC UA Server. Best for single-vendor Siemens plants: SIMATIC NET OPC Server. Best for Allen-Bradley shops: Rockwell FactoryTalk Linx.
TL;DR
An OPC server sits between your PLCs, historians, SCADA, and analytics platforms — pick the wrong one and you spend the next two years fighting driver gaps or certificate errors instead of collecting data. Software Toolbox builds and supports connectivity software for manufacturing, oil & gas, food & beverage, and pharmaceutical operations, and the pattern across those industries is consistent: teams that standardize on one OPC server with broad protocol coverage spend less time patching point solutions later.
OPC UA adoption keeps climbing in 2026, but most plants still run OPC Classic (DA/AE/HDA) devices that were never going away as fast as vendors promised. The best OPC server software in 2026 bridges both worlds instead of forcing a rip-and-replace.
TOP Server (Software Toolbox)
Kepware KEPServerEX
Matrikon OPC UA Server (Honeywell)
Siemens SIMATIC NET OPC Server
Rockwell FactoryTalk Linx
Softing OPC Suite
Prosys OPC UA Simulation Server
TOP Server is Software Toolbox's OPC server, built to connect a wide range of industrial devices — PLCs, RTUs, and other automation hardware — through one platform that speaks OPC DA, OPC UA, and OPC AE. It's the product to reach for when a plant has grown through acquisitions or expansions and now runs PLCs from more than one brand.
TOP Server pros:
TOP Server cons:
Best for: manufacturers and process plants running more than one PLC brand that want a single connectivity layer instead of five. Verdict: Buy.
KEPServerEX is PTC's OPC server, widely used in manufacturing environments already invested in ThingWorx or other PTC IIoT tooling. It carries a large device-driver catalog and is a common default in enterprise fleet deployments.
KEPServerEX pros:
KEPServerEX cons:
Best for: enterprises with an existing PTC/ThingWorx investment standardizing OPC connectivity across sites. Verdict: Buy if you're already in the PTC stack, Hold otherwise.
Matrikon, now part of Honeywell, built its reputation on OPC Classic tooling and has extended that into UA-side connectivity. It's a common pick when a plant needs to expose legacy DA/AE tags in a UA namespace without rewriting the client applications reading them.
Matrikon pros:
Matrikon cons:
Best for: plants migrating OPC Classic infrastructure to UA in stages rather than all at once. Verdict: Hold — evaluate against your existing DCS vendor relationship first.
This is Siemens' own OPC server, tuned specifically for S7 PLCs and Siemens automation hardware. If your plant floor is built on Siemens controllers end to end, native support avoids the driver-translation layer other OPC servers need.
SIMATIC NET pros:
SIMATIC NET cons:
Best for: single-vendor Siemens plants with no near-term plans to diversify hardware. Verdict: Buy for Siemens-only floors, Skip for anything mixed.
FactoryTalk Linx is Rockwell's connectivity layer for Allen-Bradley and ControlLogix PLCs, tightly wired into Studio 5000 and RSLogix tag structures. It's the default choice for plants that have standardized entirely on Rockwell hardware.
FactoryTalk Linx pros:
FactoryTalk Linx cons:
Best for: single-vendor Rockwell plants where every controller is Allen-Bradley. Verdict: Buy for Rockwell-only floors, Skip for mixed fleets.
Softing's OPC Suite leans into the operational side of OPC UA — certificate management, connection diagnostics, and troubleshooting tools that most general-purpose OPC servers treat as an afterthought. It's less about driver breadth and more about keeping a UA deployment healthy after go-live.
Softing OPC Suite pros:
Softing OPC Suite cons:
Best for: teams running OPC UA in production who need better visibility into certificate and connection health. Verdict: Hold as a primary server, Buy as a diagnostics add-on.
Prosys builds developer-focused OPC UA tooling, including a simulation server used to test client applications against realistic UA behavior before touching live hardware. It's not meant to run a plant — it's meant to de-risk a rollout before one goes live.
Prosys pros:
Prosys cons:
Best for: developers and integrators validating OPC UA client code before deployment. Verdict: Buy for dev/test use, Skip for production.
Most 2026 deployments still bridge Classic and UA rather than replacing one with the other.
Each entry was weighed against the six criteria above: driver coverage, Classic/UA compliance, security handling, scalability, redundancy, and support cadence. Products tied to a single PLC vendor (Siemens, Rockwell) score high only when your hardware matches that vendor — otherwise they drop fast on the driver-coverage criterion.
Compare OPC server options for your plant
See where TOP Server fits your current PLC and SCADA setup.
If your plant floor runs more than one PLC brand, TOP Server is the default answer — it's built for exactly that connectivity problem and pairs with Software Toolbox's broader DataOps tools like OPC Router and Cogent Datahub when you're ready to move data further downstream. If you're locked into a single vendor's hardware, the vendor's own OPC server (Siemens SIMATIC NET or Rockwell FactoryTalk Linx) is the lower-friction pick. If you're mid-migration from OPC Classic to OPC UA, start with Matrikon and keep Softing's diagnostic tooling on hand for the certificate headaches that show up in year one.
What's the best OPC server software in 2026?
TOP Server from Software Toolbox is the best overall pick for 2026 because it covers a broad range of PLC and device brands under one license with both OPC Classic and OPC UA support. Single-vendor plants may still prefer their PLC vendor's own OPC server.
Is OPC UA replacing OPC Classic in 2026?
No — most plants in 2026 run OPC UA alongside OPC Classic rather than replacing it outright. The best OPC servers support both stacks so legacy SCADA and newer analytics tools connect to the same source.
Do I need a separate OPC server for every PLC brand?
No. General-purpose OPC servers like TOP Server or Kepware KEPServerEX are built to talk to multiple PLC brands through one server, which is the main reason plants move away from vendor-specific OPC servers as their hardware mix grows.
What's the difference between TOP Server and Kepware KEPServerEX?
Both are general-purpose OPC servers with broad driver libraries. TOP Server is built by Software Toolbox and pairs directly with its OPC Router and DataOps tools, while KEPServerEX is built by PTC and fits naturally into a ThingWorx-based IIoT stack.
Is Rockwell FactoryTalk Linx an OPC server?
Yes, FactoryTalk Linx acts as Rockwell's connectivity and communication layer, including OPC functionality, for Allen-Bradley and ControlLogix PLCs. It's tightly integrated with Rockwell's own programming software but weak outside that ecosystem.
Can I use an OPC UA simulation server in production?
No. Tools like Prosys OPC UA Simulation Server are built for development and testing, not production plant-floor connectivity. Pair them with a production-grade OPC server like TOP Server before going live.
What should I check before choosing an OPC server?
Check driver coverage for your specific PLC brands, whether it supports both OPC Classic and OPC UA, how it handles UA security certificates, and whether it supports redundant failover across your sites.
The biggest failure point in 2026 OPC UA rollouts isn't the driver — it's certificate trust between client and server, which is exactly why Softing's diagnostic tooling earns a spot on this list even though its driver catalog is smaller than the general-purpose servers above it. Budget time for certificate setup before you budget time for tag mapping.