Maybe you’ve been here before too: You’re ordering your morning coffee, making small talk with your favorite, dreamy barista, when they hand you a deliciously hot drink, their fingers brushing lightly against yours. Eye contact game strong, they smile. Is this your opening? You’ve thought about leaving your number before. After all, they’re understatedly flirty, the most important provider in your life, and the first person you want to see in the morning—a recipe for love, right? Then again, maybe you’re being creepy, and they’re just doing their job. How do you tell the difference between good chemistry and good customer service?

“Read the room” is a safe place to start, says Gabrielle, a barista at a high-end New York City cafe. “That’s really the most important thing for any and all social situations.” Take environmental factors into account when deciding whether now is a good time to start your flirtation, she says: “Is it crowded? Is the barista busy, or do they have time to speak with you?”

Gabrielle has received phone numbers from several customers, always male, and while she’s never called any of them for various reasons, as long as they were respectful, she’s admired their pluck. “I think it’s a good trait,” she says. Taylor, a former barista in San Luis Obispo, CA, agrees. “If you want to leave your number for a barista, I don’t see why you shouldn’t! It is totally harmless, and maybe she or he will call.”

First, flirt

If you decide to go for it, definitely have a conversation beforehand, our barista panel advised unanimously. Beyond the obvious—helping you determine whether your advances are welcome—it will also make clear to the barista whose number they received.

“I think everyone has a story of getting a number and trying so hard to figure out who it’s from,” says Julia, who works at a coffee shop in Somerville, MA. “It makes it weird because it’s like, ‘Are you Mike with the large dark roast?’ But I think it’s totally fine to leave your number if you feel like you interacted long enough with them to feel confident that they’ll remember you and that you were getting a warm response.”

That may mean making the ask face-to-face, rather than in writing, says Taylor. “I think leaving a note is a cute idea,” she says, but the last time someone left one for her she couldn’t identify whom it was from. “It is a busy coffee shop and long shift, so I had no idea. For all I know, it could have been an 80-year-old woman (not my type).”

How do you determine whether you are someone’s type? Hard to say for sure, but Ben, who used to man the food stand at an arts festival in Laguna Beach, CA, says a cute, flirty line is a good litmus test. “Say the funny thing, and if they laugh or smile, go ahead and give the number. If their look is like, ‘Get out of my face,’ you’re not doing it for them, and it’s probably not worth your while. Keep it light and breezy. They probably get asked out all the time.”

Be respectful

Most of the baristas interviewed for this story agreed that receiving a number—whether in a tip jar, on the back of a receipt, in person, or even through Craigslist’s Missed Connections—is flattering, even if the encounter is sometimes exasperating or awkward. “I love the courage and confidence,” says Avery, currently a barista abroad and formerly a server in a Detroit pastry shop. “Definitely charming and a huge turn on.”

But there are certain situations that are simply not okay. In December, for example, a 37-year-old man in Spokane, Washington, was banned from his local Starbucks for asking out a 16-year-old barista. That’s a definite no, as is what one customer did to Katie, a Starbucks barista: “An older man, a regular, brought me a present on Valentine’s Day—a large Victoria’s Secret bag with three sparkly thongs inside. I quietly said to him that I couldn’t accept the gift, he apologized, and we left it at that.”

And keep in mind, says Alexandra, who has worked as a Starbucks barista in Cambridge, MA, and Arlington, VA, that your audience is captive—but not necessarily captivated. “You obviously can’t walk away or be rude, so it’s easy for someone to take that for you being interested,” she says. “I was on bar once, and this guy kept asking me for my number, which I wouldn’t give him, but I was in the middle of making drinks, so I couldn’t just stop and leave. He wasn’t overly aggressive in what he was saying, he just wasn’t taking a hint or take no for an answer.”

Think about the aftermath

 After a date with one customer who asked her out in person, Julia says, “he was super sweet over the next week when he came in, but then he totally ghosted.” After that, he didn’t return to the coffee shop for over a year. If you’re not willing to give up the cafe your barista crush works at, obviously don’t ghost—but also consider factors like how well you deal with rejection and how embarrassing a pickup line you opt for.

At the same time, not every date needs to lead to ever after, says Antonia, a longtime former barista in Delaware and New Jersey. “I wasn’t looking for a relationship at the time, but, my god, there were some cute guys I exchanged numbers with.” Antonia treated most of these interactions as networking opportunities and met up with several customers she felt no romantic connection with, including women, though she is straight. “I actually met someone I still stay in contact with to this day and has been beneficial in my career.” 

And if you leave a number and don’t get a text or call, says Katie, follow this unspoken rule: “No one involved should speak about it again. You don’t have to stop coming in or avoid the barista, just don’t bring it up.” Remember, your barista might have the same idea as you.

Julia’s former boss, Ray, once gave a note to a female customer they both found attractive. “It basically said, ‘If you like boys, call Ray, and if you like girls, call Julia.’ She called me, and we went out twice,” Julia says.

Gene, a Nashville-based coffee server, says that after enjoying the flattery of being asked out on his shift, he has since asked out baristas at other coffee shops. “Never know what may end up happening. I crashed and burned a few times, but nothing lost on my end.” 

Don’t make it weird

Near the beginning of her six-year career as a barista in California, Jaime was once asked by a regular customer not for her phone number but for her shoe size. “As I was a young, friendly idiot, I told him. The next day, he came to my coffee shop with custom-made Vans in my favorite colors,” she says. “Then he asked when he could take me out to wear them. I lied and told him I had four jobs and no days off.” Jaime wasn’t offended, just turned off. (She did accept the Vans, though.)

Unfortunately, says Gabrielle, it’s hard to advise against such behavior, because, as she puts it, “If you’re weird, you’re always going to be weird.”

Go for it!

“I don’t think I know any barista who hasn’t been hit on,” says Alexandra, who advises friends not to do it unless they’re “100% sure that it’s welcome.” But most of the other baristas interviewed agree with Ben, who says that as long as you’re courteous, pretty sure is good enough. “Who knows? It could be the start of something beautiful.”