Ask a Bartender: Does a Cocktail on the Rocks Have Less Alcohol in It?

With spring just around the corner, beverage aficionados are going to be asking for drinks on the rocks, or “over ice,” rather than having warming sippers done neat. Because of how easily quaffable they are, some may wonder if their drinks have less alcohol altogether. But Nikki Fairman, a beverage industry pro out of Charleston, S.C., and co-founder of The Substitutes, thinks that query needs to be flipped.

“It’s not about the subtraction of spirits,” says Fairman. “But rather, the addition of water to the drink.”

The key here is whether or not the cocktail has been diluted properly using ice while being made, or will dilute further in the glass. When ice is added to a drink, the ratios of the spirits —and as a result, the alcohol content — will remain the same. The ice will lower the proof per volume, and make the spirits smoother to drink while providing the same amount of buzz. You can expect your drink to taste less fiery, and more thirst-quenching.

“It’s really, really hot in Charleston. To enjoy a cocktail up, is to enjoy a cocktail really quickly,” says Fairman. “I personally prefer a cocktail that’s on the rocks, or ideally [with] a large cube. I feel that having some dilution in the cocktail can improve it, allowing notes in the spirit to bloom and open up a bit.”

The amount and speed of dilution depend on the type of ice in the glass as well. Larger cubes will have more surface area and will melt slower and trickle into the glass. Meanwhile, smaller cubes or crushed ice melt quickly, which is desirable for stronger drinks like a Bramble or Rum Runner.

Fairman believes there is a growing appreciation for what ice does in a drink. “I love that we’re coming into a new era where cocktails are a bit more palatable— it’s not just potent Manhattans and Negronis anymore,” Fairman says. “Water and spirits that have been together since Old Fashioneds were invented. So let’s embrace having properly diluted cocktails — I’m here for it.”