Laws related to rental payment receipts vary by state, but many require landlords to give tenants a receipt for payment. Many landlords are willing to give receipts upon request as well.
Tenants who pay their rent with cash or a money order generally need receipts to prove they made a payment. Receipts function as proof of payment, and courts may request to see receipts if this information is not listed in the landlord's records. Receipts also help tenants avoid some problems with landlords from reaching the courts, as a receipt can serve as proof that the landlord's accounting is in error. Tenants who pay with a check or a credit or debit card may want to request a receipt as well. Proving payment with bank and credit card statements is possible, but the process can be cumbersome, especially for older payments.
Since some of the money tenants pay goes toward paying property taxes, many states grant tenants tax breaks based on their rental payments and income, and landlords are typically required to provide documentation showing their tenant's annual payments. This information is also generally kept at state or county tax offices, so tenants who disagree with landlords about how much rent they've paid might be able to use this information as well.