10 things you should never do at Starbucks, according to a former employee

• Starbucks employees notice a lot about how their customers behave.
• Grabbing the wrong order off of the counter or being indecisive during a crowded time can irritate the staff.
• Leaving a mess in the bathrooms or in the sugar and milk area makes the baristas' jobs harder. 
• Adding an item to your order at the drive-through and asking for drink add-ins after you've paid can be frustrating for employees to deal with. 
• Visit Insider's homepage for more stories.

Starbucks is a major Seattle-based coffee chain that serves millions of customers each day.

Since the chain is so popular, baristas rely on good customer behavior to help make their shifts run smoothly. 

Insider spoke with former Starbucks employee Alexa Blay to find out what customers should never do at Starbucks, plus ways to make your barista's day.

Here are some things to avoid doing at the coffee chain:

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Don't collect a beverage without looking at the name on the cup.

Blay told Insider that one surprisingly common customer mistake is picking up the wrong beverage order.

"It's annoying when customers collect an order without looking at the name," said Blay. "Please take a quick second to check the name on your drink. You don't want to keep someone waiting, wondering where their drink disappeared to."

You shouldn't expect a free refill on every drink.

Coffee lovers in the know are probably aware that Starbucks allows customers to enjoy free refills on select beverages, but Blay told Insider that staff members get annoyed when customers don't know the rules.

"Some drinks are eligible for free refills, but a lot of them aren't. If free refills are important to you, ask if you'll be able to get one before you place your order," said Blay. 

According to Starbucks, you can get refills of brewed coffee (hot, iced, or cold brew), and tea (hot or iced) during the same store visit. However, the policy only applies if you purchase the original drink with a registered Starbucks card or mobile app. 

Try to avoid asking for drink add-ins after you've already paid.

Blay shared that some customers try to save a few cents by asking for beverage extras after they've already paid for their drink.

As you might expect, employees don't appreciate this tactic. 

"Please don't ask for add-ins that cost money after you've already paid," she told Insider. "If you want your drink to include flavored syrup or additional shots of espresso, please ask for it when your order is being taken."

Staff typically understand if you forgot to swap dairy milk for non-dairy, but don't purposely try to sneak in toppings or flavors after your card has been swiped.

Never leave a mess at the sugar and milk area.

Staff really appreciate when customers take a moment to clean up after themselves at the sugar and milk area. 

"If you drip milk everywhere and have lots of empty sugar packets, please throw the empty packets away and wipe up the spilled milk," said Blay. 

If you accidentally make a mess that's too big for you to handle alone, it's always a good idea to alert staff so that they can take care of it. 

Ordering off of the "secret menu" can be a real headache for baristas.

Though it's true that many Starbucks stores offer unlisted menu items, don't expect your barista to know how to whip up every special concoction you've read about online.

"Your barista might know how to make some of the secret menu items, or they might not. It depends on how often it's ordered and how new the employee is," said Blay. 

To maximize your chances of getting that off-menu item, Blay said, know the drink's ingredients ahead of time so that it can be made for you based on a description instead of just the name.

When seating is available, customers shouldn't take up more space than they need to.

Although many Starbucks locations are not currently offering seating amid COVID-19 concerns, when options to dine-in are available, it's wise to be courteous. 

As Blay told Insider, it's considered rude to use more seating or table space than necessary. 

"Don't take up more space than you need," said Blay. "It's not okay to monopolize an entire four-person table for hours at a time if there are people standing around looking for a seat."

Keeping cords, jackets, and bags off of unoccupied tables and chairs can also help make space for more people. 

You shouldn't add an extra item to your order when paying at the drive-through.

When you're in a rush, it can be easy to make a mistake at the Starbucks drive-through. However, Blay explained, requesting an extra drink or snack at the payment window is a huge pain for employees. 

"If you've already paid, please realize that it's not your turn anymore and you should probably go to the back of the line to order something else," said Blay. 

If you forget to ask for something you want, your best option may be parking and ordering inside or simply going around the drive-through again.

It's rude to leave trash or paper cups in the restroom.

Blay told Insider that staff members get annoyed when customers take their used cups, wrappers, and cutlery into the restroom and leave them there. 

"It's definitely annoying when customers leave excess food and trash in the restrooms," she said. "There's no reason to leave trash there. Please be tidy and respectful."

If the trash cans in the dining area are full, alert a member of staff instead of tossing items in the restroom.

You might want to avoid getting in line if you don't know what you want to order yet.

Between seasonal items and countless drink options, it's easy to get overwhelmed by the menu at Starbucks.

But Blay told Insider that she dislikes when customers join the line without deciding on their order. 

"During peak hours, it's annoying if customers don't know what they want by the time they reach the register," she said. "It keeps other customers waiting and they'll likely be frustrated by the time they get to the front of the line."

Blay noted that baristas are happy to answer questions about the menu or give customers allergen information at the register — but try to have at least narrowed down your options by the time it's your turn to order.

Never knock on the front door and ask for staff to let you in before opening time.

No matter how badly you need a caffeine hit, don't expect Starbucks staff to let you into the store before the posted opening time.

This rule applies even if you see employees inside the store. 

"There's an entire checklist of things the employees have to do before they can open the store, and they really can't open 15 or 30 minutes early for an early bird customer," said Blay.

Read more:

• I was a Starbucks barista for 2 years, here are 12 of the biggest things I learned
• Former employees reveal the best and worst things to get at Starbucks
• The 8 things you should never do in a coffee shop, according to employees
• 4 things you may be doing when ordering coffee that actually annoy your barista