Can I ignore it?
You can. But the letter does not go away. If the calls really happened, ignoring the letter usually makes it cost more, not less.
What ignoring does
The date in the letter passes. The sender notes that you did not answer. Then the file goes to lawyers.
The lawyers can file a lawsuit. A person delivers court papers to your business. From that day, a court deadline is running. If you miss it, the court can enter a judgment against you for the whole amount without hearing you. That judgment is public and can be collected from your business bank account.
Why it costs more
Two reasons.
First, the letter was a warning. A court can look at a business that was warned in writing and did nothing and decide the violations were willful. That changes $500 per message to as much as $1,500 per message.
Second, the letter lists the calls the sender knows about. A lawsuit lets the other side look at all your records. Every call to everyone. The number in the letter was for a few calls. The lawsuit is about all of them.
The one time ignoring is right
When the letter is fake. No real company behind it. No specific calls listed. A demand to pay by gift card, crypto or wire to a person. Pressure to pay today over the phone. Keep that letter, report it, and move on.
A letter from a company you can find in a state registry, listing real calls to real numbers on real dates, is not that letter.
"They send thousands. They cannot sue everyone."
They do not have to. They have to sue enough. The businesses that ignored the letter are the easiest to sue, because the proof is already collected and the warning is on file.
If you already ignored it
Write now. Say you are late. Say what you are doing about it. Ask if it can still be settled. Most senders will say yes.
What you should do instead
Stop calling the numbers in the letter. Keep every record. Find out if the person said yes. Not sure what counts as a yes? Read what is consent. Then pick a path: pay or dispute. If the calls are yours and nobody said yes, pay. It is the cheaper path, and it ends.
Short questions
How long after the date do they sue?
There is no set time. It can be weeks or months. The claim lasts four years from the call, so quiet does not mean gone.
If we stop calling, does the claim go away?
No. Stopping prevents new claims. The calls already made are still owed.
We never got a second letter. Does that matter?
No. There does not have to be a second one. The first letter was the warning.
Can the owner be sued personally?
Sometimes, if the owner directed the calls. That is a question for a lawyer, and a reason not to let a letter become a lawsuit.