What it actually watches, in the FTC's own list. Identity monitoring services may tell you when your information shows up in a change of address request; in court or arrest records; in orders for new utility, cable or wireless services; in an application for a payday loan; in a request to cash a check; on social media; and on websites that identity thieves use to trade stolen information.
That list rewards reading twice, because it explains the product's real value and its real limit at once. Several of those events are genuinely early: a change of address request, a utility account and a payday loan application are all things someone does with your identity before they get anywhere near your credit file, and a credit report would not show any of them. So identity monitoring covers a category of harm credit monitoring structurally cannot. Equally, every item on the list is a detection after the fact. Nothing on it is prevented by the service noticing it.
The second list is the one worth reading before buying. The FTC also publishes what these services will miss: "Most identity monitoring services won't alert you if someone uses your information to file a tax return and collect your refund, get Medicare benefits, get Medicaid benefits, get welfare benefits, claim Social Security benefits, or claim unemployment benefits."
Five of those six are claims on government benefits and the sixth is a fraudulent tax return. Those are among the frauds a person is least likely to discover on their own, because nothing about them shows up in a household's ordinary paperwork until a return is rejected or a benefit fails to arrive. A household deciding whether to pay for this should know that the harms it is most afraid of, someone else collecting its refund or its benefits, sit largely outside what the FTC says the product covers.
A structural blind spot the FTC's lists do not address either way. The service looks for "new or inaccurate information about you", which presupposes that the information is filed under you. A fabricated identity built on a real Social Security number but a different name and date of birth is, by construction, a different person in the records. Whether any given service surfaces that is a question for the vendor rather than something the FTC's guidance answers, and it is worth asking directly if that is the risk you are buying against. Our page on synthetic identity fraud explains why that case is so hard to see.
What it is not, since the four products are routinely bundled and routinely confused. It is not identity recovery, which the FTC describes as access to counselors or case managers who help write letters to creditors, place a freeze and work through documents. It is not identity theft insurance, which reimburses the cost of cleaning up rather than the money taken, and which has its own page here. And it is not a credit freeze, which is the only one of these that actually prevents rather than detects, is free, and does not expire on its own.
The first question is whether you are already paying for it. The FTC notes that you might pay a company for one or get it "through your bank or credit union, credit card provider, employer's benefits program, or insurance company", and free monitoring is usually offered with a breach notice. A subscription bought in response to a breach notice frequently duplicates one the same household already holds.