Depending on what airline you fly, you might get a notification or email asking if you want to check-in before your flight. Some people choose to ignore this and some people don’t get this alert at all if they’re flying a budget airline, but it can save you so much time and even money if you take advantage of it.
There are budget airlines like Ryanair that actually charges you 50 euros or more if you don’t check in at least a few hours before your flight, which is horrifying and the worst-case scenario. While there aren’t many airlines like this, you should definitely read the fine print and if not, check-in online as soon as you can just in case.
Even for airlines that allow you to check in later or even just at the airport, you should avoid it and check-in online. Not only will it make you so much faster since you’ll already have your boarding pass, but you also won’t have to wait online and you can use your phone as your ticket! This doesn’t mean that you should get to the airport too late though since you need to go through security, but checking in online can still shave off some airport waiting time which is always good.