Can you spot the unexpected charge on this restaurant receipt?

A diner who decided to "splurge' on a "nice dinner" at high-end Sydney restaurant Aria has been left shocked by a charge on their bill at the end of the night.

"Decided to splurge a bit and go to a nice dinner for a special occasion at Aria," they later shared on Reddit's 'Sydney' thread.

"We don't really go to these high-end restaurants often. I can understand the charge for sparkling but is it normal to charge $10.50 for still water at restaurants at this price point?"

The diner has shared a screenshot of the receipt which shows a $10.50 charge for a bottle of "sparkling water" and the same charge for a bottle of "still" water.

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On the bill we see the charges for both bottles of water, some alcoholic drinks and two orders for four course meals at a cost of $195.00.

The total bill is $455.00.

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One of the diner's Reddit followers speculated the charge is standard for "still water", which high-end restaurants price higher than "tap water" which is much less, if not free.

"You should specifically ask for table water or tap water," they explained. "But in the context of the final bill, probably not much. I have a bigger problem with the CC surcharge from places that charge this much. I'm sure they won't be happy if you pay using coins."

Another confirmed this, commenting: "Yep that's right - when the waiter asks 'sparkling or still?' you need to say 'tap.' A friend of mine is a manager at a fancy restaurant and yes this is standard practice at high end places."

"I got caught on this a few weeks ago," another shared. "They asked, 'sparkling or still?' and I asked for tap water, and they countered with 'do you mean still?', and my brain in cruise control said yes, $11 per bottle."

Others took issue with the charge, with one writing: "So dumb. It's not uncommon for nice places to even say sparkling is complimentary. That's how's it should be."

"I got burnt by this once, when they asked sparkling or still, I assumed the still would be free. I now know to ask for tap," another shared. "My partner chugged all of the water though once he saw the price, he said he was bloated but worth it haha."

"I would be more annoyed at paying $4.55 to use my credit card to pay the bill," another shared.

"It's the assumption that because you are paying so much for dinner, you won't care about the water price," one person suggested.

Aria Sydney has been contacted for comment.