Talking about money is a complicated topic and if the person was not planning on paying they may not have enough money to be able to pay. This is a polite way to suggest that you split the bill. I hope that this helps :)
When you want to divide the bill with someone and share the expenses, then you may propose this ideas using one of the expressions above. 'To go Dutch' is slightly old fashioned these days, but older people will understand this saying.
勘定を他の人と分担して支払いたいときには、上記の表現を使ってそれについて提案できます。
'To go Dutch' は今では少し古風な言い方ですが、年齢が上の人なら理解してくれます。
Lets go halfies on the bill.
Let's split the bill this time.
I think we should split the bill.
I'll get mine this time.
You get yours and I'll get mine.
Please split the bill with me.
Let's share the bill.
Sometimes we will also say, "I''ll get the bill and you get the tip".
Let's go halfies on the bill.（割り勘にしましょう）
Let's split the bill this time.（ここは割り勘にしましょう）
I think we should split the bill.（割り勘にしませんか）
I'll get mine this time.（ここは割り勘にしましょう）
You get yours and I'll get mine.（割り勘にしましょう）
Please split the bill with me.（割り勘にしましょう）
Let's share the bill.（割り勘にしましょう）
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たまに次のように言うこともあります。
"I'll get the bill and you get the tip".
「私は勘定を払うからあなたはチップを払って」
When you want to share the bill with someone so you both pay it then you can say 'let's split the bill' or 'let's share the bill'
To say to go 'half's' means to pay half the bill each
費用を割り勘にしたいときには、次のように言えます。
'Let's split the bill'
'Let's share the bill'
（割り勘にしましょう）
'to go half's' は「勘定を半分ずつ支払う」という意味です。
If you want to share half of the final bill with another person, then a common phrase to use is, "Let's split it," or "let's split the bill." If the bill is already handed to you by the cashier or waiter, then you can also simply say, "Let's half it." Another word for bill is also check. So it would also be appropriate to say, "Let's split the check." You can also use the longer phrase, "I want to pay my half." Or if you already have your payment ready, you can also say, "Here is my share for the bill." This means that you would have the appropriate amount of money ready to pay.
勘定を誰かと半分ずつ支払いたいなら、"Let's split it"（割り勘しよう）や "let's split the bill"（同）がよく使われます。
レジ係やウェイターから既に請求書を受け取っているなら、シンプルに "Let's half it."（割り勘しよう）と言うこともできます。
また、"bill"（請求書）は "check" ともいいます。ですから、"Let's split the check." と言うこともできます。
少し長いフレーズ "I want to pay my half"（割り勘しよう）を使ってもいいです。
あるいは、もしもう既にお金が準備できているなら、
"Here is my share for the bill"（これ私の分です）
と言うこともできます。自分の支払う分が準備できているわけです。
It's very common to split a restaurant bill with other people, but it would be polite if you asked them beforehand by saying "can we split the bill?" or "do you want to split the bill?"
Sometimes in American restaurants, the waiter/waitress will ask if you want "separate checks", which means each person pays separately so you don't have to split the bill. You can also receive one bill/check to pay together. However, sometimes the server doesn't give you the option and it's assumed all meals will be on one bill.
A more common way of saying "bill" (the amount due for the meal) is also "check". You'll hear phrases like "check please!" or "can we get our check?" when people would like to pay and leave after their meal.
レストランで勘定を割り勘にすることはよくありますが、前もって "Can we split the bill?"（割り勘にしていいですか）や "Do you want to split the bill?"（割り勘にしましょうか）と尋ねると丁寧です。
アメリカのレストランでは、ウェイター/ウェイトレスが「 "separate checks"（別々の勘定）にしましょうか」と尋ねてくることがあります。「それぞれが別々に払いますか」という意味です。その場合、"split the bill" する必要はなくなります。勘定を分けずに一緒にしてもらうこともできます。ただ、時々サーバーが何も聞いてこないことがあります。その場合おそらく一つの勘定になります。
"bill"（飲食店の請求書）のより一般的な言い方は "check" です。食事が終わって支払いをしたいときには、"Check please!"（お勘定お願いします）や "Can we get our check?"（同）などと言います。
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