Unless you are paid immediately upon providing a service or product, your business will have to deal with late or unpaid accounts. You can hire a debt collection service or handle the problem yourself. The US Fair Debt Collections Act was initially meant to control the practices of debt collecting companies against consumers. However, over time some states have passed even more stringent laws which regulate anyone collecting debts.
The US Fair Debt Collections Act does not control Business-to-Business transactions.
If you are collecting money from individuals, do NOT:
Information from: https://www.americanexpress.com/us/small-business/openforum/articles/getting-paid-youre-owed-without-breaking-law/
Full text of the US Fair Debt Collections Act