15% Off✦ Verified
15% off
15% Off Select Items at COS
90% chance
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Save at COS with verified coupon codes, promo codes and exclusive offers.
6
Codes
3
Verified
20% Off
Best Deal
Updated Aug 15, 2026 · 3 verified
Best code right now
10% off
Verified — confirmed working
15% off
15% Off Select Items at COS
10% off
10% Off Storewide at COS
More codes — may have expired
20% off
20% Off Storewide at COS
15% off
15% Off Storewide at COS
10% off
10% Off Linen Popover Shirt at COS
TrulyThrift currently tracks 6 COS coupon codes, of which 3 are verified working. The best available discount right now is 20% Off. Page last verified Aug 15, 2026.
Save at COS with verified coupon codes, promo codes and exclusive offers.
Visit COS ↗| Offer | Discount | Type | Status |
|---|---|---|---|
| 10% off | 10% Off | Percent | Verified |
| 15% off | 15% Off | Percent | Verified |
| 10% off | 10% Off | Percent | Verified |
| 20% off | 20% Off | Percent | Unverified |
| 15% off | 15% Off | Percent | Unverified |
| 10% off | 10% Off | Percent | Unverified |
Truly Thrift verifies COS codes through a three-layer system: automated checkout testing, cross-source corroboration, and real shopper reports. Verified codes show a green badge; other codes show their recent chance of working. Code health is a per-code reliability score built from that evidence — right now the 6 codes listed for COS carry an average code health of 54%. Read our full verification process for details across every store.
Direct checkout testing currently covers Shopify storefronts, with more platforms rolling out over time. Until COS is covered, Layers 2 and 3 below carry more of the weight for this store's codes.
For codes we can't test directly, we check whether independent coupon listings still show the same code as active. If independent sources agree a code is gone, we downgrade or hide it — even before a shopper reports back.
Every "Worked" / "Failed" button on this page feeds straight into these codes' scores. No shopper reports have come in for COS this week yet — yours would be the first.