How do I get rid of musty smell in a basement apartment?

Get rid of the moisture first—that’s what causes the musty smell.

Do this:

• Run a dehumidifier and keep humidity around 30%–50%.
• Use fans and, if helpful, an air purifier with HEPA + carbon filter.
• Open windows only when the outside air is drier than inside.
• Clean any visible mold or mildew on hard surfaces with white vinegar and dry the area well.
• Wash bedding, curtains, and removable covers; sprinkle baking soda on carpets or rugs before vacuuming.
• Place activated charcoal or baking soda in closets and corners.

Also check for the source: leaks, seepage, wet walls, or plumbing problems. If the smell keeps coming back, tell your landlord or call a mold/water-damage pro—odor usually won’t stay gone until the moisture problem is fixed.