Sheets, one pillow per person, basic towels
Toothbrushes, soap, meds, toilet paper
Chargers, extension cord, scissors, box cutter
A first-night box checklist only works if it is strict. It should cover one evening, one morning, and the small emergencies that show up before the rest of the house is unpacked.
Most first-night box lists remember bedding and chargers, then miss the things that stop the night cold: medication, shower curtain, hand soap, pet setup, and a way to make coffee or a simple breakfast.
Use one reserved color and tape the label on two sides. The point is not to make it look special. The point is to make sure nobody buries it under six identical bedroom boxes.