Talk isn’t cheap.

The secret to becoming more attractive to the opposite sex? Good conversation — at least according to a survey of 2,000 adults released Tuesday by Plenty of Fish. Indeed, the dating site found that nearly nine in 10 people (87%) said that they have found someone better looking after a good chat.

Experts agree: “Conversation is very important on a date, because it establishes how interesting and exciting a person is — traits that most people find attractive,” explains David Bennett, a relationship expert and author of “Be Popular Now: How Any Man Can Become Confident, Attractive, and Successful (And Have Fun Doing It).”

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So what do you need to reveal about yourself in the conversation to make the person fall for you? The biggest thing is that you seem intelligent (47% said that someone seeming smart in a chat made them better looking), followed by a sexy voice (40%) and a sense of humor (34%).

On the flip side, bombing conversation will almost certainly work against you, with 85% of people having found someone less attractive after talking to them, the survey found. The top explanations for that? Having nothing in common (61%), coming across as mean or insensitive (58%) and having misaligned values (57%).

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So how can you use this data to make a great impression on your date? First, make sure you have things in common to talk about, by looking up the person online (a dating profile is often a good way to do your homework) and noting a few hobbies or likes that you two might have in common before the date. Try to work in the commonalities seamlessly into the conversation. Indeed, a study on relationships released last year in the Journal of Personality and Social Psychology concluded that “whether a relationship develops could depend on the level of similarity the two individuals share from the beginning of their meeting.”

Another tactic: Make sure that you seem smart, which is about far more than your IQ. What you wear can make you seem smarter (skimpy clothing is a no-no), as can how you speak (don’t swear a lot or pause for too long between statements) and keeping the number of drinks you have to a minimum.

Whatever you say to make the date go well, one thing is certain: It’s probably going to cost you. The average unmarried American spent $1,596 on their dating life last year, according to Match.com — with residents of cities like Washington D.C. ($1,788) and New York ($2,069) dropping even more. This includes everything from bar tabs and dating site memberships to new clothes and dating events. Men tend to spend a little more ($1,855) than women ($1,423).