Look for information rather than a label
Smart casual can cover a remarkable range of clothes. One office may mean a shirt and dark trousers; another may be comfortable with trainers and a sweatshirt. If you are already working there, notice what people wear when doing work similar to yours. A visitor presenting to a client may dress differently from someone spending the day at a desk.
Think about your own tasks as well. You may need to bend, lift, use equipment, walk between buildings or spend hours in a warm room. Those requirements matter more than an outfit photograph that does not show the working day. Follow any actual safety or uniform rules before considering the style of the clothes.
Build a middle option
A pair of trousers or clean, undamaged jeans, a plain top and a removable layer can provide a useful starting point when denim is permitted. Choose familiar pieces so that fit is one less uncertainty. A soft jacket or cardigan is often easier to adjust than an outfit that depends on a formal blazer staying buttoned.
Keep the shoes suited to the journey and workplace. If you need to change them on arrival, make room to carry the second pair without overloading your bag. Do not choose an untested shoe simply because it looks more professional.
Ask a specific question
If the uncertainty matters, ask whether there are restrictions on jeans, trainers or sleeveless tops, rather than asking only what smart casual means. A clear answer about two or three items is easier to use than another broad description. Ask about differences between ordinary days and client meetings too.
There is no need to rebuild your wardrobe immediately. Wear a small group of suitable clothes, observe the environment and adjust after you have useful information. Repeating a clean, comfortable outfit is less distracting than spending the day in something that feels wrong for the job.
Keep one slightly more formal combination in mind for a change of plans. It might involve a shirt in place of a T-shirt, rather than an entirely separate set of clothes. A workable office wardrobe grows from the days you actually have.
