Their Shopify checkout only lets you plug in one promo code at a time—it straight up rejects a second one. Your best workaround is grabbing their pre-discounted starter kits or waiting for their BOGO sales. If you have loyalty points, cash those in solo, since they wipe out other discount codes anyway.

They take the usual cards, PayPal, Apple Pay, and Shop Pay. If you want installments, Sezzle shows up at checkout. Just a heads-up on mobile: hitting the express PayPal button can accidentally skip the promo code field. Make sure you expand the order summary and type your code in before tapping buy.

Never pay full price on 310 Nutrition. Just load your cart, enter your email, and bounce. They almost always send a 15% or 20% code within an hour. Note that on mobile, the discount box is hidden inside the order summary dropdown. Otherwise, pick the subscription to get 25% off, then cancel it right away.

Yeah, there's no cancellation fee for 310 Nutrition subscriptions. Just make sure to cancel inside your account portal at least a day before the renewal date so you aren't charged. Honestly though, you can just click 'skip shipment' instead. That keeps the 25% sub discount active for later without hitting your card.