A federal law, the Fair Debt Collections Practices Act (FDCPA), limits the time of day and different ways a debt collector can communicate with you.
Under the FDCPA, a debt collector isn't allowed to contact you at any "unusual time" or at a time that it knows, or should know, is inconvenient for you. Unless you tell the collector otherwise, the FDCPA says that a collector should assume that it's inconvenient to call you before 8:00 in the morning or after 9:00 at night, local time.
The FDCPA also prohibits debt collectors from harassing you. If a debt collector contacts you repeatedly, multiple times daily, or calls you intending to annoy, abuse, or harass you, then the collector is most likely violating the FDCPA.
Under the FDCPA, if you don't want a debt collector to contact you, you can stop all communications by sending a written request, commonly called a "cease and desist letter," to the collector.
If you send a cease and desist letter to a debt collector, that collector has to stop contacting you except to tell you that:
Be aware that telling a debt collector to stop contacting you is not always a good idea.
Keep in mind that the FDCPA applies to debt collectors but usually not to creditors collecting debts they originated. The law does apply to a creditor that collects its own debts under a different name. The term "debt collector" includes someone who regularly collects debts for others or whose main business is collecting debts.
Some debt buyers that purchase, and therefore own, the debt they're trying to collect aren't subject to the FDCPA. (See Henson et al. v. Santander Consumer USA Inc., 137 S.Ct. 1718 (2017)). However, the FDCPA applies to a debt buyer if the business's principal purpose is the collection of debts. (See Tepper v. Amos Financial, LLC, 898 F.3d 364 (3rd Cir. 2018), 12 C.F.R. § 1006.2(i), effective November 30, 2021, see official interpretation).
Besides the FDCPA, various states have enacted consumer protection laws that regulate debt collection practices, which could cover creditors and debt buyers.
Also, if a creditor calls you late at night, the call might be considered an "unfair or deceptive act or practice" under the Fair Trade Commission Act (FTCA).
If you're receiving harassing calls from a debt collector, creditor, or debt buyer, consider talking to a debt relief attorney to determine what you should do in your particular circumstances.
And if you have a lot of debts, you might want to consider filing for bankruptcy. In that situation, you'll want to talk to a bankruptcy lawyer.