A North Carolina bartender has revealed how many customers leave the bar without closing out their tabs. 

Bartender Michelle Kimball posted a viral TikTok video showing how many tabs she had to complete at 2.30am after a busy Saturday night.

In the video Kimball, who has a TikTok following of 4.8 million, shows the  the huge number of receipts of 'walk out' customers.

'These are the open tabs, the tabs nobody closed out for, y'all are not going to believe this' Kimball said.

The bartender's colleague then dragged the line of receipts around the large bar.  

'Now for all 372 of those tabs I get to go in here and add 20 percent tip to every single one' she explained. 

'Thank God I can do math really quickly' she joked. 

In a separate video Kimball answered a user's question about whether bartenders dislike when tabs aren't closed before a customer leaves. 

'First of all no' Kimball explained, 'we appreciate that you started a tab.'

'It takes so much longer if you just get one beer each time and close out each time instead of starting a tab.

'Second, if you walk up to the bar and it is so busy and you can't get a bartender's attention right away that means we are making drinks for other people, aka we're making money. 

'So if you just leave without tabbing out and you were already going to tip 20 percent, we love you.

'It takes so much less time to close you out at the very end of the night and then just add the 20 percent' she added. 

Some viewers of the video agreed that leaving an open tab with the expectation of a 20 percent tip is a helpful practice. 

'When the bar is busy and I know they will close with 20% tip I feel like I'm doing both of us a favor but correct me if I'm wrong' one user  wrote in the comments.    

'It’s actually cheaper for the bar to swipe your card just once. Those swipe fees can be killer for the business' another added in agreement. 

While many are happy to leave a customary 20 percent tip a recent study found that three-quarters of Americans believe tipping culture has gone too far.

The findings come amidst a widespread backlash against 'tipflation' which has seen tipping culture spill out from bars and restaurants and into stores, takeout chains and even self-service machines.

84 percent of respondents to the CouponBirds survey argued that the minimum wage should be increased to off-set the need for gratuity.

Across the board, tipping was most common for restaurant service. Some 59 percent of consumers said they would tip at dinner while 43.8 percent they would for food delivery.

It was followed by hairdressing and beauty services - which 41.1 percent of individuals said they would tip for.

Some 39.6 percent said they would add gratuity in a taxi while 36.8 percent said they would tip at a bar.

The least likely place shoppers would tip was at a convenience store or Bodega. Some 4.9 percent of survey respondents said they would add gratuity in this instance.