Reuters
There's a bit of science behind it as well, and if you know what signs to look for, you can increase your chances of getting in and out of the grocery store faster.
The New York Times interviewed experts on queuing theory - which is the science behind standing in line - to identify the best tips for picking the fastest lines.
Here's what they came up with:
1. Don't bee-line to the express lane. Often times getting behind a shopper with a full cart is smarter than queuing up in an express lane. That's because greeting customers and exchanging payment information is a huge time suck, taking about 41 seconds on average per customer, according to the Times. Ringing up items takes just three seconds per item, by comparison.
"Think of it this way: One person with 100 items to be rung up will take an average of almost six minutes to process. If you get in a line with four people who each have 20 items, it will take an average of nearly seven minutes," Times author Christopher Mele writes.
2. Pick lines on the left side of the store. Lines at registers to the right of a store tend to move slower, because most people are right-handed and tend to gravitate in that direction as a result, Robert Samuel, founder of service that stands in line for you, told the Times.
3. One single line that feeds into multiple registers is faster than standing in separate lines for each register.
That's because the mathematical odds are stacked against you when you're trying to pick the fastest of more than two lines.
4. Choose female cashiers - they are allegedly faster according to experts interviewed by the Times - and avoid getting in line behind elderly people, because they tend to have more difficulties checking out than younger people.
Read the full story on the Times' website to see more tips for checking out faster.