PROPER IS NOW SONNET
Welcome Back.
50% OFF
Your return to Core Sleep starts with a subscription.
You chose Core Sleep before. Subscribe today and make your nighttime routine easier to keep going.
The name changed. Our focus did not.
You first knew us as Proper. Today, we are Sonnet. We are still focused on making better sleep simpler.
FEATURED IN
Melatonin-free nighttime support
MELATONIN-FREE
Core Sleep is Sonnet's foundational nighttime formula, combining four thoughtfully selected ingredients to support a calmer bedtime, restful sleep, and a simple nighttime routine.
WHY CORE SLEEP
Supports an easier transition into sleep
Helps promote a calmer nighttime routine
Supports restful, quality sleep
Melatonin-free for customers who prefer to avoid melatonin
Designed to support waking feeling refreshed
INGREDIENTS
Venetron® Rafuma Leaf — 50 mg
Sensoril® Ashwagandha — 125 mg
Valerian Root — 300 mg
GABA — 100 mg
SUBSCRIPTION DELIVERY
QUANTITY
Bottle
Pouch
CORE SLEEP REVIEWS
WHAT CORE SLEEP CUSTOMERS SAY
READ ALL CORE SLEEP REVIEWS
YOUR RETURN OFFER
50% OFF
Start a Core Sleep subscription and make your nighttime routine easier to keep going.
Frequently Asked Questions
Is Sonnet the same brand I knew as Proper?
Yes. Proper is now Sonnet. You're in the right place to return to Core Sleep.
How do I get my 50% return offer?
Start a Core Sleep subscription using the offer link from your email. Your discount should apply automatically when possible.
Can I use the 50% offer on a one-time purchase?
No. The 50% return offer is available only when you start a Core Sleep subscription.
When does my 50% offer end?
Your 50% return offer is available through Monday, September 7, 2026.
Ready to come back?
50% OFF
Core Sleep Subscription
YOUR CART
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
© 2026 Sonnet. All rights reserved.
Our Commitment
Continually innovate to create the most evidence-backed approach to improving your long-term sleep health
Happiness Guarantee
Sleep isn’t one-size-fits-all. Many see improvements the first night and full benefits after several weeks. If that's not the case, please reach out and let us know - we'll work to make it right.