Some cracks are cosmetic; others signal structural movement. Knowing which is which saves you both worry and money.
Usually Minor
Thin, hairline cracks in drywall or a fresh slab are often just curing or settling and may only need cosmetic attention.
Time to Act
Wide cracks, stair-step cracks in brick, horizontal cracks, or cracks paired with sticking doors and sloping floors point to foundation movement. When in doubt, a free inspection gives you a definitive answer.