9 Best Red Dots for the SIG P365

The P365 is an incredibly popular compact handgun, but finding red dots that are compatible with it can be difficult. Even with the use of adapter plates (which Sig does not make), you can only get certain red dots to mount properly on the P365. 

In this article, I’ve done a lot of the research for you and can verify that all 8 of the red dots we’ll be reviewing here not only work on the P365 but they are particularly well-suited to it.

A Note on the Sig Sauer P365

Sig manufactured several models of the P365, and as of the article’s writing, they are all optic ready except for the Nitron Micro-Compact, the SAS, and the Born and Raised models.

That said, Sig customer support told me directly that optic-ready slides are being rolled out to be standard on the Nitron and SAS (you can already buy replacement slides with optic plates), which should have been done by Q2 of 2023. That transition may have already occurred, depending on when you’re reading this article. 

The Born and Raised is a promotional model that is unlikely to continue in the long run and, therefore, unlikely to receive an optic-ready update.

All other models of the P365, whether in 9mm or .380, should come optic-ready out of the box. With that clarified, let’s get this party started. Here are my choices for the eight best red dots for the Sig P365.

Also Read: Best Holsters for SIG P365

Product Reviews

1. Holosun HS407K-X2

Holosun makes great red dot sights in general, and the 407k-X2 is no exception. The Holosun will go on the P365 with no additional mounting plates, and the rear of the plate doubles as a rear sight for co-witness with BUIS (backup iron sights). You’ll find that most sights in this class also have the rear sight integrated in the back.

The biggest drawback, in my opinion, is that there’s no automatic brightness setting for those who want it. That may not be a big deal for you, but with how sensitive the shake-awake feature is, I’d rather not have my red dot stay on at full brightness while it’s riding around on my hip each day because I forgot to turn it down after shooting at the range.

That said, you can also disable the shake-awake feature and just practice the motion of activating the dot when you draw. If you want to maximize your battery life, that’s the best way to go anyway. 

Your dot is 6 MOA, which is great for going on a compact handgun, and you have 12 brightness settings, 2 of which are night vision compatible.

Holosun’s warranty is excellent, the company has been around for a long time, and the Holosun is the safest bet for getting the performance you want out of your P365.

Pros:

• Shake-awake (which can be disabled)
• 12 brightness settings
• 2 NVD-compatible brightness settings
• Lifetime warranty

Cons:

• No automatic brightness adjustment
• A bit pricey

2. Sig Sauer Romeo Zero

I don’t want to shock anyone, but the sight Sig Sauer designed explicitly for the P365 is an excellent option for the P365.

The biggest thing in the Romeo Zero’s favor is that you can purchase your P365 with the Zero pre-mounted and pre-zeroed for you. Those who are more experienced with handguns may not be as incentivized by that service, but someone who hasn’t installed an optic on a handgun before may really appreciate it.

If all you’re looking for is an accurate red dot that will get you out and shooting quickly, it’s hard to argue against the Romeo Zero. It has a 3 MOA dot, which is a bit smaller than I would personally want but does allow you to shoot with more accuracy and precision than a larger dot would. 

It has eight brightness settings, none of which are rated for night vision, and MOTAC powers it on automatically when it senses motion. You can turn off the MOTAC and power it on and off manually if that’s your preference.

That’s about as far as the features go, which is honestly fine. The Zero is dependable, rugged, and accurate, and that’s about all you need for a carry gun like the P365.

Pros:

• Guaranteed flawless compatibility with P365
• Can order P365 with Zero pre-mounted and zeroed
• MOTAC, which can be disabled if preferred

Cons:

• No auto brightness
• No NVD-compatible brightness
• Button is a little hard to find and reach to adjust

3. Crimson Trace CTS-1550

The CTS-1550 is a pretty cool sight, and it has a lot to offer, depending on your preferences. The first thing to be aware of is that it is made of polymer, not aluminum. This can be a big turn-off for a lot of folks (understandably so), but the 1550 is designed to hold up to the recoil of compact 9mm handguns.

Crimson Trace has a limited lifetime warranty, and the company is pretty good about honoring it, so if you find that your sight keeps losing zero or gets damaged, you should be able to get a replacement at little to no cost.

It also has exclusively automatic brightness adjustment. The ambient light sensor works well, and CT even includes a cover that you can put over the sight to ensure complete darkness (which will power off the reticle). If you want a fully automated solution (after you zero it) and are comfortable using the BUIS if the sight malfunctions at a critical moment, then the CTS-1550 could be the sight for you.

The dot is 3.5 MOA, and thanks to the automatic brightness adjustment, the battery life is rated to 20,000 hours. This sight uses the Shield RMSc footprint, so it should be able to mount up just fine with no alterations. 

Pros:

• Great price
• Sophisticated light sensor & automatic brightness
• Good warranty

Cons:

• No manual adjustment whatsoever
• No manual on/off
• Polymer construction

4. Burris FastFire II & III

Right out the gate, let me clarify that if you want to put a Burris FastFire on your P365, you’ll need an adapter plate. This will cost a little bit extra and require you to replace the factory irons with suppressor-height iron sights if you want to be able to co-witness. 

So why is it on this list? Because it’s an otherwise fantastic sight. Burris’ warranty is not “lifetime” or limited in any way. It’s their “Forever” warranty that is similar in scope (pun totally intended) to Vortex and Leupold. Red dots get a lot of use if they’re on a handgun, and Burris stands by their warranty pretty well.

If you already have a FastFire, it’s almost definitely worth picking up an adapter plate (like this one here) and putting it on your P365. Even if you don’t already have one, it’s worth considering. I’d recommend the FastFire III over the II if the price is no object because the II has the same major flaw as the Crimson Trace: brightness is controlled automatically with no option to switch to manual.

The III gives you the ability to go back and forth, plus it’s easier to zero than the FastFire II. Other than that, the differences between the two sights are minimal.

Pros:

• Forever, “no questions asked” warranty
• Automatic brightness settings
• All metal construction

Cons:

• No shake awake or MOTAC
• Auto-off is set to 8 hours and is not adjustable
• No manual brightness adjustment unless you get III
• Have to buy a separate adapter plate

5. Holosun HE507K – GR X2

The 507K is a lot like the 407K that I chose as the best overall, but there are a few key differences that might actually make this one preferable, depending on your situation. The most obvious one is that the GR version is, as you might expect, a green dot instead of a red dot.

Green dots aren’t very common for sights this small since many concealed carry situations will be at night or in other low-light situations, but that doesn’t mean a green dot can’t work great. The 507K has 12 brightness settings, 2 of which are compatible with night vision, so you’ll be able to use this in all the same situations as the 407K.

The 507K also has three different reticle options. You can get a 2 MOA dot, a 32 MOA circle, or a combination of both.

A 2 MOA dot is smaller than makes sense for concealed carry, in my opinion, so if you aren’t a fan of circle reticles, you may want to look at some of the other options on the list because the 507K is only great if you’re going to use either the circle or the combination reticle.

Beyond the green color, reticle choices, and higher price, it’s essentially the exact same optic as the 407K.

Pros:

• Green reticle
• Toggleable reticle options
• Holosun’s warranty

Cons:

• Dot is 2 MOA
• May pay for features you won’t use

6. Shield Sights RMSc

The RMSc from Shield Sights belongs on this list because it will work well with the P365 out of the box with no adapters needed. That said, I’ll be honest and say that I would only consider the RMSc if I had specific reasons to ignore the first five optics on this list.

The best thing that it offers that none of the other sights do is the ability to choose an 8 MOA dot version, which is the largest on this list. You can also choose a 4 MOA dot version. The other main difference is that you can pick up a version with a polymer lens instead of a glass lens.

There’s an obvious trade-off happening here: the polymer lens will be tougher than the glass, but you’ll experience a noticeable lack in image quality. Despite my instinct to favor the glass, there’s a good case to be made that the extra toughness is more important when it comes to a concealed carry firearm like the P365. Up to you, though.

The RMSc has really good automatic brightness adjustment, but it also does not let you adjust it manually. Therefore,  if it malfunctions or isn’t the right brightness for the situation, you either have to just deal with it or rely on the iron sights.

Pros:

• Out-of-the-box compatibility with P365
• 8 MOA dot option
• Polymer lens option

Cons:

• Glass lens versions cost more
• No manual brightness adjustment
• Price is higher than the value offered

7. Swampfox Sentinel

The Swampfox Sentinel is a direct response to my main complaints with the Shield RMSc: it’s a lot cheaper, has high-quality glass lenses (which don’t cost extra), and you can choose a version that has manual brightness adjustment.

Now for the reasons it’s not higher on the list.  You can’t toggle between manual and automatic brightness, you have to purchase one version or the other, and the Swampfox warranty is weird. 

Let me explain. It’s a “50,000” round warranty as opposed to a “limited lifetime” or “forever” warranty. That’s weird to me because unless they’ve installed some kind of sensor in their sight that records the number of times it’s hit with recoil, then neither Swampfox nor the firearm owner will have any idea if or when they’ve crossed the 50,000-round threshold.

So when it comes to the question of whether your sight is still under warranty, you get the worst possible answer: “maybe.” If it’s a clear yes or no then you can make good decisions based on that, but when it’s ambiguous it gets a lot harder.

Despite my gripes with their warranty, the Sentinel makes it on this list by having great features, and build quality. And positive reviews from abundance make it one of the best sights for Glock 43x.

Pros:

• Tough metal & glass construction
• 3 MOA dot
• Choose between manual or automatic versions

Cons:

• Warranty makes no sense
• Can’t toggle between manual/auto, have to choose which version to buy.

8. AT3 Tactical ARO

The AT3 Tactical ARO is a great choice for people who have a healthy distrust of electronics and automatic options. It doesn’t come with any sort of shake-awake or motion-sensing technology, and it doesn’t offer automatic brightness settings. If you want it on, you have to turn it on. If you want it brighter or dimmer, you have to turn it up or down.

It does have an auto-off feature after 6 hours of use, which should give you plenty of time to either train at the range or fight your way through an army of bad guys, but that’s the extent of any automation.

It’s a standard 3 MOA dot, 6061 Aluminum body, and is very standard in most ways. To get it on your P365, you’ll need the same adapter plate as the Burris FastFire (which you can get here), and it will also go fairly easily on just about any firearm you want to put it on. You can even purchase it with an absolute co-witness mount in case you ever want to mount it on an AR-15.

What makes the AT3 a great fit for the P365 is that the price reflects its simplicity. You’re not paying for all the fancy features, so if you don’t want those fancy features anyway, the Tactical ARO could be the best option for you.

Pros:

• Solid construction
• 3 MOA dot
• Wide compatibility with other guns besides P365

Cons:

• No auto brightness
• No motion sensor
• Requires adapter plate for P365

9. Sightmark Mini Shot M-Spec FMS

Let’s talk about the Sightmark Mini Shot M-Spec FMS to finish up this list. The Sightmark offers essentially the same value as the AT3, but it will go on the P365 with no adapter plate necessary. 

It also has motion activation that you can turn off if you don’t want it. You’ve got ten fully manual brightness settings with no automatic option—the same standard 3 MOA dot, with similar waterproofing, battery life, and durability to the AT3.

It also has an automatic shut-off, which kicks in after 12 hours compared to the AT3’s 6. So if you’re turned off of the AT3 because you don’t recognize the brand name or for any other reason, the Sightmark is a great alternative and may even be superior depending on your specific use case. Sightmark is a well-known company with a good reputation.

You won’t enjoy all the nice features from some of the sights higher up on the list, but again, if you don’t want those features in the first place, why pay for them? The Sightmark is noticeably cheaper and could give you all the utility you need out of a red dot sight for your P365.

Buying Guide

The Sig Sauer P365 is a line of compact and ultra-compact handguns, similar in size and purpose to the Glock 43, 42, and 26. The P365’s role as a handgun specifically for concealed carry has implications for the type of optic you want to put on it.

Footprints & Adapters

The Sig P365 uses the Shield RMSc footprint, though if you talk to Sig customer support, they’ll refer to it as the Romeo Zero footprint. You can see a list of some popular sights that use this same footprint here. 

If you buy a red dot that uses a different footprint, it will not work on your P365. Sig does not make any adapter plates to put any other sights on the P365 (probably because they would prefer everyone just use the Romeo Zero), but you can find adapter plates made by other companies like this one.

Dot Color & Size

Generally speaking, when you’re planning for an event in which you may be forced to use your concealed carry handgun, it’s much more likely that being able to quickly get a semi-accurate shot (within a few inches) will be more important than being able to shoot with MOA accuracy. For this reason, I recommend going for the largest possible dot or a dot-circle combo.

Unlike size, color really doesn’t matter unless you have astigmatism, but every shooter gradually develops a preference for one or another over time. If you’re unfamiliar with reflex sights, I would say to pick based on other features and not worry about the color of the reticle.

Also Read: 3 MOA vs 6 MOA Reticle

MOTAC & Shake-Awake

Generally speaking, I really like motion-activated red dots. The reason for this is that it can take crucial time and focus to manually power on your red dot when you’re in a life-threatening situation. The last thing I want to do when I’m terrified out of my mind is miss the power button on my red dot a few times with my thumb before finally being able to get a sight picture.

This could be mitigated a lot by simply hitting the range more often, but for a working stiff like me with three kids, it’s hard to prioritize more range time than I need just to draw quickly and shoot accurately, especially when I can remove the need to do so by simply buying a red dot that kicks on for me.

Motion activation isn’t a perfect solution, though. If you’re carrying, the red dot is almost guaranteed to be on all the time because it’s moving around with you. If you remember to turn the brightness all the way down or have automatic brightness, then you’ll get the 20,000 – 50,000 hours of run time that most sights offer.

Automatic Brightness vs. Manual Brightness

Automatic brightness is another feature to consider. Some folks love it, some folks hate it. If you’re going for a sight that has motion activation of some kind, I’d recommend considering automatic brightness, especially if it’s easy to toggle on and off. 

The biggest risk with automatic is that it will give you a dot that’s either too dim to see quickly or so bright that it obscures your target area. 

The biggest risk with manual is that you have it set to one brightness level because of how you shot it last (or expected to shoot it next), and then the moment you need it is a completely different lighting situation.

You could get stuck having to fiddle around with the brightness instead of engaging the assailant, or, God forbid, you take a poorly-aimed shot because your reticle was either too dim or too bright.

Build Quality

Carry guns may seem like they have a pretty cushy life just riding around on your waist all day, but they can actually get quite a bit of mileage over time. Your sweaty hairy torso is no cake-walk, and carry guns often need to get left in glove compartments (better be a lockable one), portable safes, or in purses or luggage.

If your carry gun is sharing space with a pair of shoes or another hard object on occasion, it’s smart to prioritize an optic that can stand up to that kind of treatment.

Image Quality

Red dots for carry guns are probably the only class of optic for which I would say this, but image quality isn’t a big deal for these. Obviously, you need to be able to clearly see your target, but none of the decently-rated sights you can pick up are going to have cloudy optics. You’re talking about the difference between “clear enough” and “really clear.”

Frequently-Asked Questions

Also Read: Best Red Dot Sights & Reflex Sights

Conclusion

There may not be as many sight options for the P365 as there are for some other handguns, but there are still plenty to choose from. The one that rises to the top for me is the Holosun HS407K-X2 red dot sight. It offers night vision compatibility, shake-awake, and 12 different brightness settings. 
The dot is a good size at 6 MOA, it’s tough, strong, multicoated, and waterproof. If you’re ready to pick up the 407K-X2, you can do so at this link. Thanks for reading, and let me know if there’s anything I missed in the comments!