OPNsense vs pfSense in 2026

The fork happened in 2015. Deciso, a Dutch hardware vendor, took the pfSense codebase, rewrote the web interface, changed the release model, and called it OPNsense. What followed was several years of a genuinely unpleasant argument between the two camps, involving a typosquatted domain, some public accusations, and a great deal of forum heat that produced very little light.

That is history now, and mercifully so, because it made the technical comparison almost impossible to have honestly for years. Every thread was contaminated by the feud. Eleven years on, both projects are mature, both are good, and the feud is a footnote that mostly matters as an explanation for why the old advice you find on the internet is so tribal.

I have run both on real hardware, and I have installed OPNsense on the box that currently guards my own network. The reasons for that choice have changed a lot since the last time I wrote about it, and I want to lay out what the comparison actually looks like now rather than what it looked like in 2018.

The shared foundation

Both are FreeBSD. Both use pf — OpenBSD’s packet filter, ported — as the actual filtering engine. Both give you a web UI over a system that is, underneath, a fairly ordinary BSD box with a lot of PHP generating config files.

That shared ancestry means the capability lists are nearly identical, and the list is long: stateful filtering, NAT in all its forms, VLANs, multi-WAN with failover and load balancing, traffic shaping, IPsec, WireGuard, OpenVPN, DHCP and DNS services, captive portal, HA failover via CARP, IDS/IPS via Suricata, and a plugin catalogue for the rest.

The packet-forwarding performance is, for practical purposes, the same. Both handle a gigabit line on modest hardware. Both will do 10 Gbit with enough CPU and the right NICs. Anyone claiming a meaningful throughput advantage for either is measuring something other than what you care about, because the thing doing the work is the same pf on the same kernel. What differs is everything around it.

Where they genuinely diverge

Release cadence. OPNsense ships two major releases a year, in January and July, with security updates weekly. pfSense CE ships when it ships — the gaps between CE releases have stretched to a year and beyond, and CE has visibly lagged behind pfSense Plus, the commercial version. If you want a firewall that receives predictable, frequent updates, OPNsense’s model is simply better, and the gap here is the single biggest change since the fork. This is not a small thing on a device whose entire job is facing the internet.

The CE and Plus split. This is the point that should weigh most heavily. Netgate’s pfSense Plus is the version that gets the features and the attention; pfSense CE is the free one, and the relationship between them has grown steadily less comfortable. Plus is free for home use on your own hardware, with a registration and an account, and the terms of that arrangement are Netgate’s to change. CE remains open source and is where the community lives. The strategic question — is the free version a first-class product or a funnel — has an answer that has been drifting in one direction for years.

OPNsense has no equivalent split. There is a business edition with a support contract and some enterprise-oriented extras, and the community version is the same software with the same features. That structural difference is worth more than any feature comparison in the table.

The web interface. OPNsense’s UI is cleaner, more consistent, and better organised. pfSense’s is denser and, for anyone who learned it years ago, faster to navigate precisely because it has barely changed. Some of the OPNsense rearrangement is genuinely better — the firewall rule editor, the dashboard widgets — and some is change for its own sake. This is largely taste, and anyone telling you their preference here is objective is telling you about themselves.

Plugins. OPNsense’s plugin system is more actively developed and the catalogue is broader. Both cover the important things. OPNsense’s are generally better integrated into the UI; pfSense’s packages have a longer track record of stability.

Underlying base. OPNsense moved to HardenedBSD for a period and then back to a hardened FreeBSD base with selected mitigations. pfSense stayed on FreeBSD throughout. In practice this affects almost nothing you will notice, and the marketing on both sides oversells it.

WireGuard. Both have it, both work. pfSense’s history here is memorable: the kernel implementation was pulled in 2021 after a code review found serious problems, and it came back later via a different route. OPNsense’s has been steady. Ancient forum threads still relitigate this and it is settled on both sides now.

The comparison table

Both are worth having over the alternative

It is easy to lose sight of this while comparing two similar things. The gap between either of these and the router your ISP supplied is enormous — real rules, real logging, VLANs, and a segmented network where the cheap devices cannot reach the valuable ones. The gap between OPNsense and pfSense is small enough that choosing wrong costs you very little.

Both let you drop to a shell and treat the box as the BSD system it is, which is where the config actually lives:

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$ pfctl -s rules
scrub in all fragment reassemble
block drop in log inet all label "Default deny rule IPv4"
pass in quick on em1 inet proto tcp from 192.168.10.0/24 to (em1) port = 443 keep state
pass in quick on em2 inet proto udp from any to any port = 53 keep state

$ pfctl -s state | wc -l
    1847

$ pfctl -s info
Status: Enabled for 41 days 06:22:14           Debug: Urgent
State Table                          Total             Rate
  current entries                     1847
  searches                        891204412        251.2/s
  inserts                           4128891          1.2/s
Counters
  match                             8129447          2.3/s
  bad-offset                              0          0.0/s
  fragment                              117          0.0/s

That is pf on both platforms, and it is the same output. The UI is a config generator sitting on top of this. Knowing that is what lets you debug either box when the interface is lying to you, and it is why the skills transfer completely — a week with one makes you competent with the other.

The hardware question, which matters more than the software one

Something worth saying loudly: the box you run this on will determine your experience far more than which of the two you install. The requirements are effectively identical, so the advice below applies to both.

Network cards decide everything. Intel NICs work. Realtek NICs are the source of a disproportionate share of every “my firewall randomly drops connections” thread on both projects’ forums, because the FreeBSD drivers for them have always been the poor relation. A second-hand Intel card costs less than a takeaway and eliminates an entire category of intermittent misery. Buy one before you buy anything else.

CPU matters only for the extras. Plain routing and NAT at gigabit is nearly free on any x86 chip made in the last decade — pf is efficient and the work is small. What eats cores is IDS/IPS inspecting every packet against tens of thousands of signatures, and VPN throughput. A four-core mini-PC with AES-NI comfortably runs a gigabit line with Suricata and a couple of WireGuard tunnels. A dual-core fanless box will route gigabit fine and then fall over the moment you enable inspection.

RAM is cheap and states are not free. 4 GB is workable, 8 GB removes the question. Suricata with a full ruleset will take a couple of gigabytes on its own, and the pf state table grows with every device in the house.

Storage should not be a USB stick. Both write logs and RRD graphs continuously, and cheap flash dies of it. A small SSD is the difference between a firewall that lasts eight years and one that corrupts its config in eighteen months.

The unglamorous conclusion: a used office micro-PC and an Intel NIC outperform most purpose-built appliances at a third of the price, and either OS runs happily on it.

What I would tell someone choosing today

Choose OPNsense if you are starting fresh. The predictable release cadence matters on an internet-facing device, the absence of a two-tier product structure removes a strategic question you would otherwise have to keep answering, and the UI is friendlier to someone learning. This is what I run and what I recommend by default.

Choose pfSense if you already know it. The muscle memory is worth real money, the software is good, and switching to gain a slightly better dashboard is a poor use of a weekend. Familiarity with the tool that guards your network has genuine safety value — you will make fewer mistakes on the interface you know.

Choose pfSense Plus if you buy Netgate hardware. The integration is good, the support is real, and if you want a supported appliance rather than a project, that is a coherent thing to buy. It is also the version Netgate cares most about, which counts for something.

Choose neither if your hardware is a Raspberry Pi. Both want x86 and both want a couple of gigabytes of RAM; ARM support is an ongoing frustration on both sides. Run a Linux router with nftables instead and accept that you are trading a GUI for hardware you already own.

Troubleshooting either

The failure modes are shared, because the underlying system is shared.

“I locked myself out.” The perennial one, and the reason both ship an anti-lockout rule on the LAN interface by default. If you disabled it and then wrote a bad rule, the console menu is your route back — option 3 resets the filter to defaults on both platforms, and it works over a serial cable when nothing else does. Keep a serial cable. Actually keep one; the day you need it is the day you cannot order one.

“Rules do not match what I expect.” pf evaluates rules last-match-wins by default, and quick short-circuits that. Both UIs generate quick on nearly everything, which makes the rule list read top-down as most people expect. When behaviour surprises you, pfctl -s rules shows the truth, and the truth occasionally differs from what the UI implies.

“Throughput collapsed after an upgrade.” Check whether hardware offloading changed state. Both platforms disable various NIC offloads by default because pf and offloading interact badly, and an upgrade can reset that. Also check that a state table limit has not been hit — pfctl -s info shows current entries against the limit, and a busy network with the default limit will start dropping connections in a way that looks like a bandwidth problem.

“The IDS is dropping legitimate traffic.” Applies to Suricata on either box, and the answer is the same: run in IDS mode until you have tuned the ruleset, then promote specific rules to blocking. An untuned IPS on a family’s internet connection is a support ticket generator.

“HA failover flaps.” CARP needs a dedicated sync interface and a network that carries multicast reliably. A cheap switch that is unhelpful about multicast will cause both nodes to believe they are master, which produces an address conflict and an afternoon of confusion.

The verdict

The honest summary is that this decision does not matter nearly as much as the internet’s tone would suggest. Both are competent BSD firewalls running the same filter engine. Both will do everything a home network needs and most of what a small office needs. The performance is identical. The skills transfer. Anyone who tells you one is dramatically better is describing a feud from 2015 rather than the software as it exists now.

My tiebreaker is the release model and the product structure, and both of those point the same way. A device whose only job is standing between my network and the internet should receive security updates on a schedule I can predict, and it should not have a free tier whose relationship to the paid tier is a question I have to keep revisiting. OPNsense answers both cleanly, which is why it is on the box guarding my network and has been for years.

If you run pfSense and it works, keep it. Genuinely. The best firewall is the one whose rule list you understand at 11 p.m. when something is broken, and the same logic applies to your switching and wireless kit — familiarity is a feature, and churning your infrastructure to chase a marginally better interface is how homelabs turn into hobbies about themselves rather than tools that work.