Thirdlove offers a "Try Before You Buy" option when you complete the Fit Finder on their website. They'll send you one of the recommended bras for just the $4.99 shipping charge. After 30 days, if you decided to keep it, your payment method will be charged for the price of the bra.
Thirdlove's loyalty program "Hooked" is also well worth the free signup, especially since the upper membership levels where free shipping is a perk are unlocked by lifetime spend – most tiered loyalty programs base spend on a calendar year, so this is an unusual and valuable benefit.
Thirdlove offers free shipping on orders totaling $50 or more to Hooked members.
Thirdlove sells a wide variety of bras, underwear, and sleepwear designed to fit and flatter a broad range of body types.
Thirdlove's loyalty program is called Hooked Rewards. Members get free standard shipping on orders of $50 or more and an annual birthday gift. Additional perks such as truly free standard shipping, free seamless underwear, and exclusive seasonal offers are unlocked with $250+ lifetime spend, and with even more perks at $450. Membership is free.
Thirdlove offers a 60 Day Fit Guarantee. If you're unhappy with your purchase, you can return it for an exchange or a refund within 60 days of purchase.