Let's clear something up before getting into this list. You don't need every plugin on the market to make top-of-the-line, professional quality music. Over the years I've acquired countless plugins. Some people collect vinyl, some people collect comics... I collect plugins. It may or may not be a borderline addiction, but I haven't found myself sleeping in a back alley, trading food stamps for plugins... yet.
The funny thing is that I only use a handful of plugins when producing, mixing and mastering. Every now and then I'll reach for a specific tool to accomplish a specific job, but for the most part I get away with using a limited number of devices.
When I started my music production journey, like most people, I had no idea which way was up. On top of knowing next to nothing about music theory, I had absolutely zero understanding of audio engineering. I just really liked listening to music and wanted to start making it. Discovering that you can use third-party software inside your DAW doesn't help much with the information overload.
To get you through this, I've compiled a list of all the best plugin companies that I've come across. Hopefully it will provide you with a bit of confidence when making your next buying decision. Remember to bookmark this page so that you can refer back to it later. These are the companies that I believe to be the heaviest hitters in the plugin game:
Plugin Boutique
They don't make plugins, but they offer discounts on really popular plugins from other companies, and provide you with loyalty points that you can cash in for discounts. I always recommend referencing plugin prices here before buying from somewhere else (even the plugin company's website).
Plugin Fox
This website doesn't make plugins either, but they offer discounts on really popular plugins from other companies, and provide you with loyalty points that you can cash in for discounts. I always recommend referencing plugin prices here before buying from somewhere else (even the plugin company's website).
Antares
They make the official Auto Tune, as well as other pitch and voice manipulation plugins.
Cableguys
All their plugins are good, but the one of note is VolumeShaper. It performs volume automation and sidechain volume automation. To learn more about mixing with Volume Shaper, check out this guide on 7 Ways to Mix Your Kick and Bass Together.
Celemony
They make Melodyne which is industry standard for natural pitch correction.
East West
Their multisampled libraries are some of the highest quality I've used.
Eventide
They have an assortment of reverb plugins that are definitely worth checking out. Blackhole works particularly well for cinematic sounds. They also sell an assortment of plugin effects, plugin emulations, and utility devices.
FabFilter
Highly recommended mixing and mastering tools.
Illformed
They make Glitch2, which is a great FX plugin.
iZotope
Highly recommended mixing and mastering tools.
Klanghelm
If you're looking for some mixing tools with a lot of character, check out Klanghelm. It's a nice bonus that all of their plugins are affordable as well.
LennarDigital
Makers of the synth Sylenth1.
MeterPlugs
They offer cutting-edge metering plugins.
Native Instruments
They make a wide range of synths and mixing tools. Kontakt, their multi-sampler, is one of my essential production tools.
oeksound
They currently offer a cutting-edge mid-high frequency resonance suppressor called soothe, and a transient shaper called spiff; both of which are unmatched by any other company.
Plugin Alliance
Highly recommended mixing and mastering tools. Sign up for their newsletter to receive insane product discounts of up to 80% off.
Slate Digital
For $14.99/month you can get all of their mixing and mastering plugins.
Sonarworks
This company produces a software called Reference that compensates for the imbalanced frequency response of your headphones and monitors. This allows you to make mixing and mastering decisions that will translate better across different playback systems.
Sonnox
Their Inflator plugin is particularly interesting. Its job is to increase apparent loudness without sacrificing sonic quality.
Soundtoys
As far as plugins go, these ones contain more analog character than anything else I've used.
Spectrasonics
I use their Omnisphere synth in almost every song I write.
Synchro Arts
They make pitch and time correction software that helps line up vocal doubles and harmonies.
u-he
They make a handful of synths and variety of different audio effects. The Uhbik bundle is extremely popular.
Universal Audio
These plugins require an Apollo interface due to the way they process signal. A big investment, but definitely worth it due to their quality.
Waves (Save 10% with This Link)
Highly recommended mixing and mastering tools. Waves has different plugins on sale every day. They also occasionally offer huge discounts on their plugin bundles. The Waves Gold Bundle is my top recommendation if you're just starting out with music production, and the Waves Horizon Bundle is an essential if you're producing music at a semi-professional to professional level.
Waves Factory
This company makes a plugin called TrackSpacer that will help mould all of the elements in your song together using dynamic EQ.
Xfer Records
Most notable is the wavetable synth they make called Serum. I doubt you'll find a producer who doesn't own it.
XLN Audio
If you're looking for realistic drums, Addictive Drums 2 is something you're going to want to have a look at.