LOS ANGELES — At the end of a long day, cooking a meal might be the last thing you want to do. So you open one of the food delivery apps on your phone (Uber Eats, DoorDash, Postmates, Grubhub, to name a few) to find something you’re hankering for.

The problem is by the time you actually hit order, you might be paying twice the price of your meal in delivery fees and decide that instead of paying even more money, your delivery driver is going to have to deal without a tip.

A study from US Foods shows 66% of food delivery app customers base their tip on how much the delivery and service cost them. The good news is that 95% of customers still tip regularly, but 60% of drivers say no tip or a small one is their No. 1 complaint.

“It’s already expensive, but that’s not the fault of your delivery driver, who is getting in their car, working for wages of their own and delivering you the food,” said etiquette expert Diane Gottsman.

So, how much should I tip my delivery driver?

That depends on who you ask, but, generally, both customers and drivers agree that $4 is a fair tip, according to the study. However, that might be low depending on the amount of food you order.

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Gottsman suggests tipping at least 20% of the total cost of the meal, or at least $5.

“They are working for gratuity as well,” said Gottsman. “That is part of their livelihood, and I think we should tip politely and appropriately,”

There are other things you should consider when you tip:

Tip in cash: Some food delivery apps use tip money as a way to avoid paying the driver their full payments, as The New York Times recently found with DoorDash. So if a driver is owed a $5 and you tip $2, the app pays them $3 instead of adding the tip as extra. DoorDash changed their tipping model since the article’s publication, but the easiest way to ensure the driver gets the full tip you are paying is to give them in cash.

Some food delivery apps use tip money as a way to avoid paying the driver their full payments, as The New York Times recently found with DoorDash. So if a driver is owed a $5 and you tip $2, the app pays them $3 instead of adding the tip as extra. DoorDash changed their tipping model since the article’s publication, but the easiest way to ensure the driver gets the full tip you are paying is to give them in cash. Do your research: Some delivery services don’t actually require you to tip or have a guide on how to tip their drivers. Look at their website and see what their expectations are.

Some delivery services don’t actually require you to tip or have a guide on how to tip their drivers. Look at their website and see what their expectations are. Consider the circumstances: Think about things like how far does my driver have to drive? How far do they have to park? How many flights of stairs do they have to climb? What’s the weather outside? And factor that into your tip, especially if it’s extraneous.

Think about things like how far does my driver have to drive? How far do they have to park? How many flights of stairs do they have to climb? What’s the weather outside? And factor that into your tip, especially if it’s extraneous. Tip for future service: If you plan on using one specific app or service for a long time, let them know you’re a good customer and tip them fairly. You’ll probably get better service.

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Hey, drivers, you can do things to make sure you get that tip money, as 50% of customers decide on their tip on a case-by-case experience. Customers complain about drivers staying in their car or dropping off the food at the door and leaving. And whatever you do, do not take food from the order – customers really don’t like that, as 85% say restaurants should tampering labels on their delivery orders to ensure no one messes with their order.

And customers, consider giving your driver a bonus if you like them by writing them a good review either on the app or through other rating services. It will go a long way for them.

Follow Madeline Purdue on Twitter.