Part 1 of Plain-English IT from Quarterhorse, a short series on the tech that keeps small businesses and schools running.
If your office or school has a SonicWall firewall that is a few years old, there is a good chance it stopped getting security updates this year. SonicWall ended support for its older "Gen 6" firewalls in stages during 2026. The last group, including the TZ350, TZ500, SOHO 250 and the NSa 4600 to 6650 models, lost support on October 1, 2026.
Most people never notice. The firewall still turns on. The internet still works. That is exactly what makes it risky.
What "end of support" really means
A firewall is the front door to your network. It decides what gets in and what stays out. When a model reaches end of support, SonicWall stops doing three things for it:
No more firmware updates. When hackers find a new weakness in that model, it does not get fixed.
No more technical support. If something breaks, SonicWall will not help troubleshoot it.
No more hardware replacements. If the box fails, there is no warranty swap.
Your rules and VPN connections may keep working. But every new weakness found from now on stays open. Attackers know this, and they look for old firewalls on purpose.
Which models are affected?
Here are the most common SonicWall models that are now past end of support:
TZ300, TZ350, TZ400, TZ500 and TZ600 (and their W and P versions)
SOHO and SOHO 250
NSA 2600, NSa 2650, NSA 3600 and NSa 3650
NSA 4600, 5600 and 6600, plus NSa 4650, 5650 and 6650
SuperMassive 9000 series and the older NSv virtual firewalls
Not sure what you have? The model name is printed on the front or bottom of the box. Or use our free SonicWall Firewall Lookup. Pick your model and see its support date in seconds.
You have three options
1. Replace it with a current model
SonicWall's newer firewalls, like the TZ270 through TZ670, the new TZ80, TZ280 and TZ480, and the NSa 2700 and up, are fully supported. They are also faster, so you can turn on security features without slowing down your internet. For most small offices, this is the right answer.
2. Upgrade through a SonicWall trade-in program
SonicWall often offers upgrade deals for customers moving off older hardware. A SonicWall partner like Quarterhorse can tell you what is available for your model right now.
3. Keep it and accept the risk
Some people choose to wait. If you do, know what you are giving up. An unsupported firewall is like a lock that can no longer be repaired. It might hold. It might not.
What a smooth swap looks like
Replacing a firewall does not have to mean a lost day of work. Here is how we do it for our clients:
Check what you have. We look at your current firewall, its rules, and what it protects.
Pick the right size. We match the new model to your number of users, your internet speed, and what you need to block.
Move your settings. Your rules, VPNs and security settings come over to the new box.
Swap after hours. We do the cutover when nobody is working, so nobody notices.
Watch it 24/7. After it is in, we keep it updated and keep an eye on it around the clock.
The bottom line
An old firewall can look fine right up until the day it is not. Checking takes less than a minute.
Find out where you stand. Use the free SonicWall Firewall Lookup, then book a free 15-minute review with Ken, our owner. No cost. No pressure. Just a clear answer. Prefer to talk? Call (646) 722-6500.
Quarterhorse Technology is a SonicWall security partner serving businesses and schools in New York, New Jersey, Connecticut and eastern Pennsylvania since 1999.
