I travel delta and I had one carry on, plus my personal bag
It will depend, the airlines are the ones having their own baggage's regulations. For example, Spirit, you have to pay for each bag. So its better to have one and a hand bag/backpack. Southwest on the other hand, you can have two 50 pounds or less bags/suitcases and a hand bag and they'll be free as long as it won't pass the weight and height regulations which is 50 pounds weight and the sum of the dimensions of the individual baggage no more than 62.
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