Kmart offers the Bubba 20-oz. Travel Mug, model no. 04868-WM, for $3.99. Opt for in-store pickup to avoid the $5.99 shipping fee. That's the lowest price we could find by $5. This foam-insulated mug has a tapered bottom and fits into most cupholders.
Of note, Shop Your Way Rewards members will earn a Kmart credit with this purchase and may be eligible for additional credits and discounts.