Express takes $15 off orders of $30 or more, $30 off orders of $75 or more, or $60 off orders of $150 or more via coupon code "1952". (Of note, the website advertises coupons that yield less of a discount and the coupons also don't stack with sale or clearance items ending in $.99.) They're tied with our mention from July as the best dollar-off coupons we've seen from Express this year. Shipping starts at $8 and sales tax is added where applicable. Deal ends October 14.
A best bet is the Express Men's Henley Lion Seal Graphic T-Shirt in Steel (pictured) for $49.90 before the coupon above, $34.90 after. With $8 for shipping, that's $15 off and the lowest total price we could find. It's available in sizes XXS to XXL.