Update: May 1, 2019: Unfortunately, all these nail polish subscription boxes no longer exist. While there are no more nail-polish only subscriptions, Ipsy lets you personalize your box via your profile, and they often include nail polish every month as one of the many items they sample. This isn't a guarantee that you'll receive nail polish every month, but it might be the perfect cadence for you. Check out Ipsy here.
I believe Julep Maven is the original monthly nail polish service, and I'm a big fan of this subscription. (I've been a subscriber for over a year now).
How it works: To sign up, you'll take a quick profile quiz, and they'll match you with a box profile: Classic with A Twist, Modern Beauty, It Girl, Boho Glam, or Bombshell. They release their new collection every month on the 20th, and you can go with the colors associated with your profile, or choose a different box. (FYI - Classic with a Twist, Boho Glam, and Bombshell each feature two nail polishes and one signature beauty product, It Girl features 3 nail polishes, and Modern Beauty features 2 beauty products).
In addition to the nail polish colors you pick, you also get a new beauty product from Julep. Julep Nail Polish retails for $14 a bottle, and the beauty product they include usually ranges from $25-$35, so on an average month you get over $50 of nail polish and beauty product for only $19.99.
Julep also rewards their subscribers with perks like 20% off and free shipping on anything in the Julep store, and a Secret Store that opens up once a month for 72 hours with nail polish and other items on sale at a deep discount.
COUPON: Use this link to get your first Julep Maven box for free when you buy a 3-month subscription, or get your first month for 50% off.
If you are looking for just polish and nothing else - Square Hue might be the right box for you. Each month they have a theme that they design their colors around, and they send subscribers a box of 3 new curated shades. The colors are always very current for the season, the polish formula is 3-free and Made in the USA, and the box and packaging are super cute too!
COUPON - Sign up for their newsletter to get a bonus box offer!
Bonus Points: You can easily skip or pause your subscription from your online account. AND they donate a portion of every monthly subscription to charity!
The Monthly Mani Box ($30) and The Monthly Mani Kit ($10) from SCRATCH - Free shipping to the US, $8 International
The Monthly Mani Box 3 sets of 16 nail wraps, accents & extras and a surprise gift in each box. (For the Monthly Mani Kit it is one set of nail wraps).
If you are looking to get a monthly nail polish fix and want to keep things in budget too, Color Me Monthly is a great affordable option. For $7 a month they ship one new exclusive nail polish to your door. Their polish is made in the USA and 3-free.
Want to see a list of every nail polish box? Check out the Nail Polish Subscription Box Directory!