Normal wear and tear is the gradual deterioration a unit suffers from a tenant living in it the way people live in homes, and it is a cost you absorb rather than charge against the security deposit. Think faded paint, lightly worn carpet traffic lanes, small nail holes from hanging pictures, and loose door handles: the kind of decline that would happen to any unit over a normal tenancy regardless of who lived there.
In practice
The dividing line is between aging and abuse. There is no single legal definition that every state shares, so the safest frame is the one HUD uses: wear and tear is deterioration that occurs from normal use, while damage is harm beyond that, caused by negligence, carelessness, accident, or misuse. Say a tenant moves out of a unit you painted three years ago. The walls are dull and scuffed along the hallway, and there are four small nail holes in the living room. That is wear and tear, so repainting comes out of your pocket, not theirs. Now say the same walls have a 2-foot crayon mural and a fist-sized hole patched with duct tape. That is damage you can charge for.
Carpet shows the same split. A five-year-old carpet with matted traffic lanes is at the end of its useful life from ordinary walking, so you cannot bill the tenant to replace it. The same carpet with a bleach stain and two cigarette burns is damage. When you do charge, you charge the depreciated value, not the full replacement cost: if a carpet has a 7-year useful life, cost $1,400, and was 4 years old at move-out, you have 3 of 7 years of life left, so the most you can fairly deduct is $1,400 × 3 ÷ 7, which is $600.
Why it matters to a small landlord
This is the exact spot where deposit disputes are won or lost. Charge for normal wear and tear and you have a tenant who is right and a deduction that will not survive a small claims judge, plus, in many states, a penalty for a bad-faith withholding. The defense is a record: dated move-in and move-out photos and a signed condition checklist that show what changed during the tenancy versus what was already there. The discipline of keeping that record is laid out in the security deposit paper trail, and when you do return the deposit, an itemized letter that names each deduction and its math is what ends the argument before it starts. There is a ready version in the security deposit return letter template. rents.ai records each deduction with its own description and dollar amount so the returned figure is derived from your itemized list rather than typed by hand, though it stores your photos as document attachments and does not decide for you which charges are fair.
Drawing this line cleanly is part of every turnover, and it starts long before move-out, at the move-in and move-out inspection that fixes the baseline condition. The repairs that fall on your side of the line then become part of the make-ready work that gets the unit rentable again. Get the baseline documented and the rest is mostly arithmetic.