The one simple trick from restaurants that can convince diners to leave a big tip

It seems like the heated topic of tipping culture has been an age-old debate now for decades.

With some people swearing by the 10% rule to others outright refusing to spend any extra pennies on service, it's clear we all see things very differently when it comes to handling the bill at the end of a meal.

So, to shed some light on the whole tipping thing, a bunch of researchers have shared the simple trick restaurants use to convince diners to leave a nice big tip.

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A study was published last month in the International Journal of Hospitality Management all about the nifty little trick which, when used, increased the average restaurant server’s tip by a cushty 11%.

The researchers found that doing something as simple as popping a smiley face emoji on a bill can significantly up your chances of getting a heftier tip, with the authors stating: "We establish that when emojis are included with tip suggestions during the payment transaction, customers tip at a higher percentage than when no emojis are included."

And the number of emojis seemingly make a massive difference too.

The researchers discovered that the largest tips came about when multiple emojis were shown alongside suggested tip amounts.

So, for example, more neutral face expression accompanied lower tips and, as the recommended percentage grew, so did the size of the emojis' smiles.

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Based on the study conducted at full-service restaurants, the presence of emojis saw rises in the average tip go from 22.86% to 25.38% - bringing about an overall 11% relative increase.

And it was even better for food delivery apps as the average tip jumped about 10%, from 14.66% to 16.11% with takeaway orders seeing the most growth at 32.8% with a change from 12.61% to 16.75%.

So - what is the actual science such a phenomenon?

Well, simply put, a happy emoji = happy customer.

"This effect is explained by positive emotions, such that the presence of emojis leads to a positive emotional experience for the customer, who in turn leaves a larger tip than they would when no emojis are included," the researchers explained.

When we see a smiley face, it actually stimulates a part of our brain called the occipitotemporal cortex, which internalises facial perceptions.

"Smiles are the most direct signal of positive emotions," the scientists added.

I guess 'service with a smile' really does pay off then...