A March outfit for Paris should be easy to adjust when you move indoors. Start with a thin long-sleeve top, a cardigan, straight jeans, and a coat. Try the layers together before deciding what earns space in your bag.

The Paris tourism climate guide gives seasonal context for cooler weather and rain. Check the forecast for your own week before choosing the final outer layer. Think about the long outdoor parts of the itinerary and the rooms where you will remove the coat. Keep shoes suitable for the conditions you expect and already comfortable for walking.
Build the outfit in this order:
Key points:
Macaron's personal AI can fit these layers to your Paris plans using the clothes and comfort preferences you describe. Note which layer you are willing to carry once you take it off.

Try the same coat over the blouse and trousers you might wear to dinner. Check sleeve space, length, and how the bag sits. If that combination feels cramped, a thinner middle layer may be enough. A striped top with jeans can cover the daytime outfit; the blouse and trousers give you a second base without requiring another coat.
Keep the pieces that work across both versions and add changes for your actual activities. The Paris itinerary guide covers the walking-to-dinner decisions without fixing the month. For a longer cool-weather route, compare your layers with a fall-style travel capsule. Your travel clothes can also join the rotation. The airport outfit plan starts with pieces you can wear again after landing; check that those pieces fit the March layers you selected.
That depends on the coat, the forecast, and your comfort. Try it over the layers you intend to wear to check the warmth and fit.
Choose a base you feel comfortable wearing without your coat. A removable knit gives you another adjustment if the room feels warm.
They can be if you enjoy walking and sitting in them. Consider how you will manage them if they get wet or need washing.
First try your daytime coat with the dinner outfit. Pack a second only if a specific booking or practical need justifies the space.