Convincing guests to treat themselves to tasty, high-margin drinks can mean the difference between a profitable shift and a challenging one.

With orders of free tap water increasing, according to NPD Group research, operators are seeking to increase check averages with specialty drinks.

Three beverage trends in particular have captured customers’ attention and persuaded them to indulge.

Seasonal trend: Pumpkin spice coffee

Since Starbucks introduced its Pumpkin Spice Latte a decade ago, coffee drinks flavored not necessarily with pumpkin itself but with spices found in pumpkin pie — including cinnamon, nutmeg, clove and sometimes ginger, allspice or star anise — have proliferated on autumn menus.

Online restaurant ordering company GrubHub reports that orders for menu items with the word “pumpkin” in them jump by 33 percent in October and November. Menu research firm Datassential says that virtually all pumpkin limited-time offers appear in the fall, with the remainder introduced in August in anticipation of the seasonal frenzy.

McDonald’s joined the club this year when it introduced a pumpkin spice latte at its more than 14,000 units. The drink is made with Rainforest Alliance Certified espresso and steamed milk infused with spices and pumpkin pie flavoring. It is available through November, or while supplies last, at a suggested retail price of $2.29 for a small, $2.89 for a medium and $3.39 for a large.

Coffee Bean & Tea Leaf has long had pumpkin spice drinks on its menu. This year it also touts an off-the-menu Pumpkin Chai Tea Latte.

Available to customers of the 900-unit chain who know to ask for it, the latte is made with sweet pumpkin sauce and chai spices, including cinnamon, clove and cardamom — dovetailing with flavors typically added to pumpkin spice drinks. Its suggested retail price is $3.50 for a small, $4.30 for a regular and $4.60 for a large. The latte is also available as an iced blended beverage, priced at $3.95 for a small, $4.50 for a regular, $5.35 for a large and $6.35 for a 32-ounce serving.

Paciugo, a 44-unit chain based in Dallas that specializes in gelato, has introduced a spiced pumpkin flavor to its Gelatte line.

Gelattes are lattes made by adding a scoop of gelato to the frothing pitcher along with milk. The mixture is steamed and espresso shots are added. A 12-ounce Gelatte starts at $3.09, though prices vary by location.