Having a T-Shirt and jeans would be good if you are going around visiting the country. As long as you are neat, you will be allowed into most places, including restaurants, clubs etc.

However, some places practice different dress codes, so if you are unsure, make sure you call the place you are heading before choosing what to wear. That said, if you wear a shirt with collar, and a pair of pants (men) and dress (woman), you will be allowed into even posh restaurants.

Business Attire:
If you are heading for a business appointment, it is quite important to be properly attired. Since Singapore is a humid place, it is not consider rude if you do not wear a coat to meet the person.

Long sleeves shirt with a tie would be the minimum requirements though. If you are a lady, just wear your normal working attire.

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