Click here for more information on HP Home & Office Free Shipping Offers Coupon_Code

As stated on the HP website:

Free shipping methods

Eligible products¹ ship free with orders totaling $100 or more Standard (5–7 business days) Ink and toner supplies
Paper supplies Next business day
Two business days
Standard (5–7 business days) Extended Service Plans Standard (5–7 business days) Plasma televisions Scheduled delivery

Eligible products have a free shipping message on their product detail pages, in the "Special offers and deals" promotion box.