営業時間は土日、祝日も同じですか？って英語でなんて言うの？

What are your bank holiday opening hours?
What are your weekend opening hours?
What are your holiday opening hours?

Bank Holiday- this is a national holiday in the UK

You can also say...
Are you open as usual on...(name of holiday?)
Are you open New Year's Day?
What hours are you opening over the holidays?
Do you have special openings hours over the holidays?

Hope this helps! ^ ^

Asking a store for their operating hours, you are asking when they are open from and what time they close.

I hope this helps :)

How to ask if a business is open the same hours all year round.

When you want to ask whether a shop opens for the same hours on weekends and holidays; then you may ask in the following ways:
-Are your trading hours for weekends and public holidays the same?
-Are you open during the same hours on weekends and holidays?

Weekend refers to Saturday and Sunday. Holiday may refer to a Bank Holiday in the UK.
'Do you have different opening hours weekends and holidays?'
'When are you open over the weekend?'
Being open, or open for business, could also be described as 'trading'
'We'll be trading 8-6 on Bank Holiday Monday!'

You can ask a store about their opening hours using the above two questions. Some stores have the same opening hours on weekdays and weekends, others have different hours for
weekends.

If you want to ask if a shop is open the same hours on the weekends/public holidays then you could simply say 'Are you open the same hours on weekends/public holidays?'
You could also ask 'What are your opening hours on weekends/public holidays?' you would get a more detailed answer when asking this