Both run on the same FreeBSD base. Both do stateful packet inspection, VLANs, VPNs and traffic shaping. The choice comes down to three things: update pace, UI philosophy and how much you trust Netgate.
Run OPNsense if you're starting fresh. Run pfSense if you already have it and it works.
OPNsense ships major releases every six months and minor updates roughly every two weeks. You know when patches arrive and what they cover.
pfSense CE (Community Edition) went years between major updates. Netgate pushed people toward pfSense Plus, which is free for home use but requires registration. The message was clear enough.
OPNsense uses a modern Bootstrap UI with a logical menu structure. Everything sits where you'd expect it.
pfSense uses an older interface. It works fine but feels like it was designed in 2012 because large parts of it were.
OPNsense has Zenarmor (formerly Sensei) for deep packet inspection and application control — free tier included. It also ships with a built-in firmware update mechanism that actually tells you what changed.
pfSense has a larger pool of community packages, mostly because it's been around longer. Most of the important ones exist in both.
OPNsense has native WireGuard support baked in since 22.1. pfSense added it, pulled it citing kernel stability issues, then re-added it. OPNsense handled it more cleanly.
Both run on the same boxes. The Protectli VP2420 is the mini appliance I'd buy new today — quad Intel NICs, 8GB RAM, fanless. The Topton N6005 firewall box is a cheaper option with 6 NICs if you need more ports.
OPNsense. It updates consistently, the UI is better, and the project has no corporate agenda pulling it toward a paid tier. If you're already on pfSense and everything runs fine, there's no urgency — but start new builds on OPNsense.
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